{"id":6255,"date":"2026-05-27T21:14:24","date_gmt":"2026-05-28T01:14:24","guid":{"rendered":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/?post_type=chapter&#038;p=6255"},"modified":"2026-06-11T00:58:09","modified_gmt":"2026-06-11T04:58:09","slug":"diagnosis-prognosis-and-epidemiology","status":"web-only","type":"chapter","link":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/chapter\/diagnosis-prognosis-and-epidemiology\/","title":{"raw":"Section 2 Diagnosis, Prognosis and Epidemiology","rendered":"Section 2 Diagnosis, Prognosis and Epidemiology"},"content":{"raw":"[caption id=\"attachment_6801\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-6801 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-300x123.png\" alt=\"Although medical professionals rely heavily on signs and symptoms to diagnose disease and prescribe treatment, many diseases can produce similar signs and symptoms.\" width=\"300\" height=\"123\" \/><\/a> Although medical professionals rely heavily on signs and symptoms to diagnose disease and prescribe treatment, many diseases can produce similar signs and symptoms.[\/caption]\r\n<h3><span style=\"color: #1f5c99\"><strong>Diagnosis, Prognosis, Morbidity and <span style=\"color: #1f5c99\">Mortality<\/span><\/strong><\/span><\/h3>\r\n&nbsp;\r\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\" border=\"0\">\r\n<tbody>\r\n<tr style=\"height: 31px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Diagnosis<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 31px\">The identification of the disease, disorder, or syndrome.\u00a0 An accurate diagnosis is essential for appropriate treatment and helps in making a prognosis.\u00a0 An accurate diagnosis can depend on the availability of specific tests and medical equipment.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Prognosis<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">The predicted outcome of an illness or injury.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Morbidity<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 15px\">The rate of a particular disease within a population.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Mortality<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">The typical death rate associated with a disease or disorder.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td class=\"border\" style=\"width: 18.2111%\"><span style=\"color: #032c80\"><strong>Etiology<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%\">The study of the cause of a disease, disorder, or syndrome.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<h3><span style=\"color: #1f5c99\"><strong>Etiology - Categories of Causes<\/strong><\/span><\/h3>\r\nThe causes of diseases, disorders, and syndromes can be organized into the following categories:\r\n<ul>\r\n \t<li><strong>Infectious diseases:<\/strong> caused by viruses, bacteria, fungi, helminths, and protozoa.<\/li>\r\n \t<li><strong>Immune dysfunction:<\/strong>\u00a0 illness arising from a deficient or overactive immune system (e.g., allergies, autoimmune diseases).<\/li>\r\n \t<li><strong>Trauma:<\/strong>\u00a0 bone fractures, wounds, injuries.<\/li>\r\n \t<li><strong>Nutritional deficiencies.<\/strong><\/li>\r\n \t<li><strong>Cancer.<\/strong><\/li>\r\n \t<li><strong>Lifestyle factors.<\/strong><\/li>\r\n \t<li><strong>Toxins.<\/strong><\/li>\r\n \t<li><strong>Genetics.<\/strong><\/li>\r\n \t<li><strong>Congenital defects.<\/strong><\/li>\r\n<\/ul>\r\n<span class=\"transcription-time-part\" data-time-start=\"1654.639\" data-time-end=\"1656.649\"><strong>Genetic Disorders, Hereditary Diseases, and Congenital Defects<\/strong><\/span>\r\n\r\nThree closely related but distinct terms deserve careful attention:\r\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\" border=\"0\">\r\n<tbody>\r\n<tr style=\"height: 31px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Genetic Disorder<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 31px\">An ailment caused by a<strong> DNA mutation<\/strong>.\u00a0 Mutations can be inherited or occur spontaneously during cell division.\u00a0 Exposure to carcinogenic agent also damages DNA and give rise to cancer.\u00a0 Cancer is therefore an example of a genetic disorder caused specifically by mutations in genes that control cell division (mitosis) and apoptosis.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Hereditary Disease<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">A genetic disease that has been <strong>inherited<\/strong> from a parent (e.g., Hemophilia, resulting from a mutation in a clotting factor gene).<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Congenital Defect<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 15px\">Anatomical or functional defects occurring during embryonic or fetal development, presenting at birth.\u00a0 The word comes from Latin <strong>con-<\/strong> ('with') + <strong>genesis<\/strong> ('creation of').<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\nExamples of genetic disorders you may be familiar with:\r\n<ul>\r\n \t<li><strong>Cystic fibrosis<\/strong>:\u00a0 recessive, caused by a mutation on chromosome 7.<\/li>\r\n \t<li><strong>Sickle cell anemia<\/strong>: recessive, caused by a mutation in the hemoglobin beta chain gene on chromosome 11.<\/li>\r\n \t<li><strong>Marfan syndrome<\/strong>:\u00a0 autosomal dominant, mutation on chromosome 15.<\/li>\r\n \t<li><strong>Huntington's disease<\/strong>:\u00a0 autosomal dominant, mutation on chromosome 4.<\/li>\r\n \t<li><strong>Down syndrome:<\/strong> inheritance of three copies of chromosome 21 (trisomy 21).<\/li>\r\n<\/ul>\r\n[caption id=\"attachment_2220\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2220 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-300x226.jpg\" alt=\"Sickle Cell Anemia\" width=\"300\" height=\"226\" \/><\/a> Sickle cell anemia is part of a group of genetic disorders known as sickle cell disease. In those with sickle cell anemia, red blood cells, which are usually round, flexible and flow easily within blood vessels, are sickle-shaped and lead to blockages to blood flow. This sickle shape is caused by an abnormal form of hemoglobin, a protein responsible for carrying oxygen. As a result, less oxygen is delivered to organs of the body, leading to severe consequences, including stroke.[\/caption]\r\n\r\n[caption id=\"attachment_2221\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2221 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-300x208.jpg\" alt=\"Marfan syndrome\" width=\"300\" height=\"208\" \/><\/a> A positive wrist sign in a patient with Marfan syndrome, where the thumb and little finger overlap when grasping the wrist of the opposite hand. Marfan syndrome is a genetic disorder that affects connective tissues (gives support, protection, and structure to other tissues and organs), commonly affecting the heart, eyes, blood vessels and skeleton. Individuals with Marfan syndrome are typically tall and thin, with unusually long arms, legs, and digits.[\/caption]\r\n\r\n[caption id=\"attachment_2227\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2227 size-medium\" title=\"Karyotype\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome-300x186.png\" alt=\"Example of congenital multifactorial defect: down syndrome.\" width=\"300\" height=\"186\" \/><\/a> Karyotype (an individual's complete set of chromosomes) of trisomy 21 (Down syndrome), where there is the presence of a third copy of chromosome 21.[\/caption]\r\n\r\nThe most common congenital defects include: <strong> congenital heart defects<\/strong>, <strong>hypospadias<\/strong> <span class=\"transcription-time-part\" data-time-start=\"1728.275\" data-time-end=\"1730.255\">(slight misplacement of urethra within penis)<\/span>, clubfoot (inward turn of foot), <strong>cleft lip<\/strong> and <strong>cleft palate<\/strong> <span class=\"transcription-time-part\" data-time-start=\"1728.275\" data-time-end=\"1730.255\">(incomplete fusion of right and left palatine and\/or maxillae bones in the roof of the mouth)<\/span>, <strong>limb defects<\/strong>, and <strong>mental dysfunction<\/strong>.\u00a0 Many of these can be surgically corrected or managed with physical therapy.\r\n\r\nThe causes of congenital defects are most often <strong>multifactorial<\/strong> - meaning many factors are responsible - including genetic susceptibilities, fetal exposure to <strong>teratogens.<\/strong>\r\n<div class=\"textbox textbox--key-takeaways\"><header class=\"textbox__header\">\r\n<p class=\"textbox__title\"><strong>What are Teratogens?<\/strong><\/p>\r\n\r\n<\/header>\r\n<div class=\"textbox__content\">\r\n\r\nAll agents that can cause <strong>congenital defects<\/strong>, <strong>miscarriages,<\/strong> or <strong>stillbirths<\/strong> are grouped together and called <strong>teratogens.<\/strong>\u00a0 These include:\u00a0 various microbes, alcohol, drugs, toxins (e.g., mercury, lead), gamma radiation, x-rays, and nutritional deficiencies.\r\n\r\nA growing <strong>embryo<\/strong> and later <strong>fetus<\/strong> are especially susceptible during <strong>organogenesis<\/strong> (the formation of new organs), when teratogens can have the most harmful effects.\u00a0 The severity of congenital defects typically depends on the <strong>timing, duration,<\/strong> and <strong>concentration<\/strong> of teratogen exposure, as well as the fetus's genetic composition.\r\n\r\nExamples include:\u00a0 <strong>Fetal Alcohol Syndrome<\/strong> (caused by prenatal alcohol exposure), and congenital defects caused by infections such as rubella, <strong>measles, mumps, chlamydia,<\/strong> and <strong>syphilis<\/strong> - which can cause blindness, deafness, and cognitive delay.\r\n\r\n<strong>Zika virus<\/strong>, spread by mosquito species in tropical regions (e.g., Uganda, Central America) has been linked to congenital defects including <strong>microcephaly,<\/strong> reduced brain development and cognitive impairments.\r\n\r\nThe overall risk factors for congenital defects also include maternal health, maternal age, and maternal exposure to cigarette smoke.\r\n\r\n<\/div>\r\n<\/div>\r\n\r\n[caption id=\"attachment_2216\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2216 size-medium\" title=\"Mercury contamination is a problem in the Florida Everglades\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-300x225.jpg\" alt=\"Mercury contamination is a problem in the Florida Everglades\" width=\"300\" height=\"225\" \/><\/a> Mercury contamination is a problem in the Florida Everglades, and in many bodies of water throughout the world (Photo by Tom Friedel). In the Everglades, mercury is supplied via atmospheric deposition, groundwater discharge, and stormwater run-off. Mercury content in the water and fish are so high that swimming or fish consumption should be limited or completely abstained to avoid mercury toxicity.[\/caption]\r\n\r\n[caption id=\"attachment_2217\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2217 size-medium\" title=\"Cutaneous mercury granuloma\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-300x225.jpg\" alt=\"Cutaneous mercury granuloma is a rare disorder caused by the introduction of elemental mercury (Hg) into skin. treat an open wound.\" width=\"300\" height=\"225\" \/><\/a> Cutaneous mercury granuloma is a rare disorder caused by the introduction of elemental mercury (Hg) into skin (Photo by Y. Rosen). Metallic mercury in tissue appears as black, opaque, spherical globules of varying size. They provoke a granulomatous foreign-body reaction composed of foreign body giant cells, granulomas and a mixed inflammatory infiltrate. The method of introduction could be skin penetration by a mercury-containing object or the use of mercury-containing medication to treat an open wound.[\/caption]\r\n\r\n[caption id=\"attachment_2218\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2218 size-medium\" title=\"United States Environmental Protection Agenc\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1-300x207.jpg\" alt=\"\" width=\"300\" height=\"207\" \/><\/a> United States Environmental Protection Agency (U.S. EPA) emergency response contractors clean up mercury at a Nevada home. Symptoms of mercury poisoning vary depending on exposure dose, duration, method, and type, though symptoms can include kidney and central nervous system damage, or death.[\/caption]\r\n\r\n[caption id=\"attachment_2223\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2223 size-medium\" title=\"Hypospadias\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg-300x163.jpg\" alt=\"Example of congenital multifactorial defect: hypospadias.\" width=\"300\" height=\"163\" \/><\/a> Hypospadias is a congenital malformation in males, characterized by abnormal fetal development of penis so that the opening of the urethra is located on the underside of the penis rather than the tip. In subcoronal hypospadias, the urethral opening is located just below the head of the penis. In midshaft hypospadias, the urethral opening is located halfway down the underside of the penis. In penoscrotal hypospadias, the urethral opening is located where the shaft of the penis meets the scrotum.[\/caption]\r\n\r\n[caption id=\"attachment_2228\" align=\"alignnone\" width=\"225\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2228 size-medium\" title=\"Cleft lift and cleft palate\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate-225x300.png\" alt=\"Example of a congenital multifactorial defect: cleft lip and cleft palate.\" width=\"225\" height=\"300\" \/><\/a> Cleft lift and cleft palate are among the most common congenital defects, where parts of the upper lip or palate do not fuse properly in utero. Unilateral cleft lip and\/or palates occur if the defect only occurs on one side, while Bilateral cleft lip and\/or palates occur when the defect is on both sides.[\/caption]\r\n\r\n&nbsp;\r\n\r\n[caption id=\"attachment_2224\" align=\"alignnone\" width=\"212\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2224 size-medium\" title=\"Clubfoot\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot-212x300.jpg\" alt=\"Example of a congenital multifactorial defect: clubfoot\" width=\"212\" height=\"300\" \/><\/a> Clubfoot, which affects the muscles and bones in the feet, is the most common congenital malformation (occurs in about 0.1% of births). Affected feet (can be only one or both) twist down and rotate inwards.[\/caption]\r\n\r\n[caption id=\"attachment_2225\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2225 size-medium\" title=\"Foot Abduction Brace\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-300x192.jpg\" alt=\"\" width=\"300\" height=\"192\" \/><\/a> A foot abduction brace consists of two straight-border, high-top, open-toe shoes attached to an aluminum bar, with the heels of the shoes at shoulder distance apart and the shoes themselves set at 60-70 degree angles. This device is used as part of the Ponseti method (a series of casting and orthotic brace treatments) of non-surgically treating young children born with clubfoot.[\/caption]\r\n\r\n[h5p id=\"51\"]\r\n<h3><span style=\"color: #1f5c99\"><strong>Clinical Manifestations - Signs and Symptoms<\/strong><\/span><\/h3>\r\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\" border=\"0\">\r\n<tbody>\r\n<tr style=\"height: 31px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Clinical Manifestation<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 31px\">A formal term for signs or symptoms<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Sign<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">Observable indicators of illness - fever, rash, lab test results, imaging results<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Symptom<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 15px\">Indicators of illness that are not observable by another person - pain, weakness, fatigue, nausea, headache, cramps, sleeplessness.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n&nbsp;\r\n\r\n[h5p id=\"14\"]\r\n\r\n&nbsp;\r\n<div class=\"textbox textbox--key-takeaways\"><header class=\"textbox__header\">\r\n<p class=\"textbox__title\"><strong>What is a Biopsy?<\/strong><\/p>\r\n\r\n<\/header>\r\n<div class=\"textbox__content\">\r\n\r\nA <strong>biopsy<\/strong> refers to the excision or scraping of a tissue sample, usually examined under a <strong>microscope<\/strong> for signs of disease.\u00a0 For example, a <strong>Pap smear<\/strong> involves scraping <strong>cervical cells<\/strong> and sending them to a lab where cellular morphology is examined for early signs of cervical cancer.\u00a0 The Pap smear is typically recommended every 2-3 years (as per physician recommendation) after an individual becomes sexually active.\u00a0 Early detection of cervical cancer greatly improves the chance of successful treatment.\r\n\r\n<\/div>\r\n<\/div>\r\n<h3><span style=\"color: #1f5c99\"><strong>Idiopathic and Iatrogenic Disease<\/strong><\/span><\/h3>\r\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\" border=\"0\">\r\n<tbody>\r\n<tr style=\"height: 31px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Idiopathic<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 31px\">A disease of unknown cause.\u00a0 The prefix <strong>idios<\/strong> is Greek for 'one's own'.\u00a0 The synonym <strong>essential<\/strong> is also used (e.g., essential hypertension:\u00a0 high blood pressure not resulting from a medical condition, most often linked to obesity, unhealthy diet, sedentary behaviour and family history.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Iatrogenic<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">A disease caused by the health care practitioner or by the treatment itself.\u00a0 The prefix <strong>iatro<\/strong> is Greek for 'doctor'.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n&nbsp;\r\n\r\n[h5p id=\"15\"]\r\n<h3><span style=\"color: #1f5c99\"><strong>Predisposing Factors (Risk Factors)<\/strong><\/span><\/h3>\r\n<span class=\"transcription-time-part\" data-time-start=\"1908.025\" data-time-end=\"1910.74\">A <strong>predisposing factor<\/strong><\/span> <span class=\"transcription-time-part\" data-time-start=\"1910.74\" data-time-end=\"1913.665\">is another term for risk factor - a condition or characteristic that increases a person's susceptibility to developing a disease.\u00a0 Common risk factors include:<\/span>\r\n<ul>\r\n \t<li><span class=\"transcription-time-part\" data-time-start=\"1913.665\" data-time-end=\"1915.869\"><strong>Age<\/strong>:\u00a0 Older age increases risk for cancer and many other diseases, as a lifetime of exposure to damaging agents accumulates and cells become less effective at providing protection, fighting infection and healing tissue. <\/span><\/li>\r\n \t<li><span class=\"transcription-time-part\" data-time-start=\"1919.559\" data-time-end=\"1921.675\"><strong>Biological sex<\/strong>: Females are more susceptible to autoimmune diseases and lung cancer.\u00a0 Males are more susceptible to cardiovascular disease, X-linked colour blindness, <\/span><span class=\"transcription-time-part\" data-time-start=\"1923.609\" data-time-end=\"1925.934\">and Duchenne muscular dystrophy.<\/span><\/li>\r\n \t<li><span class=\"transcription-time-part\" data-time-start=\"1925.934\" data-time-end=\"1928.095\"><strong>Genetics<\/strong>:\u00a0 Certain genetic profiles increase susceptibility (e.g., sickle cell anemia, cystic fibrosis)<\/span><span class=\"transcription-time-part\" data-time-start=\"1936.089\" data-time-end=\"1937.234\">.<\/span><\/li>\r\n \t<li><strong>Congenital defects<\/strong>:\u00a0 Some defects (e.g., congenital heart defects) can make organs less robust and more susceptible to wear and tear, injury and disease.<\/li>\r\n \t<li><span class=\"transcription-time-part\" data-time-start=\"1937.234\" data-time-end=\"1939.43\"><strong>Diet<\/strong>:\u00a0 Malnutrition impairs growth, cognitive function, and organ function globally.\u00a0 In many Western countries, diets high in fat, sugar, and\/or salt increase risk for heart disease, diabetes, and possibly <\/span>Alzheimer's disease.<\/li>\r\n \t<li><span class=\"transcription-time-part\" data-time-start=\"1950.65\" data-time-end=\"1952.899\"><strong>Occupation<\/strong>:\u00a0 Exposure to radiation, asbestos coal dust, and pollutants, increases risk for cancers and lung disease.\u00a0 Pesticide use is being linked to the onset of Parkinson's disease.<\/span><\/li>\r\n \t<li><span class=\"transcription-time-part\" data-time-start=\"2031.859\" data-time-end=\"2034.65\"><strong>Location<\/strong><\/span>:\u00a0 Geography determines exposure to local infectious microbes, sociodemographic factors, and cultural practices.\u00a0 For example, malaria is endemic to tropical regions where the Plasmodium protozoan parasite is carried by specific mosquitoes.<\/li>\r\n<\/ul>\r\n[caption id=\"attachment_2199\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria.jpg\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2199 size-medium\" title=\"RBCs infected with Plasmodium falciparum\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-300x238.jpg\" alt=\"Example of relapse\" width=\"300\" height=\"238\" \/><\/a> Electron micrograph of red blood cells infected with Plasmodium falciparum, the parasite that causes malaria in humans. Patients with malaria often exhibit a relapse of symptoms following a peak of symptoms and, occasionally, long periods of dormancy.[\/caption]\r\n\r\n[caption id=\"attachment_6799\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-6799 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-300x128.png\" alt=\"Blood smears showing two diseases of the blood. (a) Malaria is an infectious, zoonotic disease caused by the protozoan pathogen Plasmodium falciparum (shown here) and several other species of the genus Plasmodium. It is transmitted by mosquitoes to humans. (b) Sickle cell disease is a noninfectious genetic disorder that results in abnormally shaped red blood cells, which can stick together and obstruct the flow of blood through the circulatory system. It is not caused by a pathogen, but rather a genetic mutation.\" width=\"300\" height=\"128\" \/><\/a> Blood smears showing two diseases of the blood. (a) Malaria is an infectious, zoonotic disease caused by the protozoan pathogen Plasmodium falciparum (shown here) and several other species of the genus Plasmodium. It is transmitted by mosquitoes to humans. (b) Sickle cell disease is a noninfectious genetic disorder that results in abnormally shaped red blood cells, which can stick together and obstruct the flow of blood through the circulatory system. It is not caused by a pathogen, but rather a genetic mutation.[\/caption]\r\n\r\n[caption id=\"attachment_6803\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-6803 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-300x153.png\" alt=\"The Zika virus is an enveloped virus transmitted by mosquitoes, especially Aedes aegypti. The range of this mosquito includes much of the United States, from the Southwest and Southeast to as far north as the Mid-Atlantic. The range of A. albopictus, another vector, extends even farther north to New England and parts of the Midwest.\" width=\"300\" height=\"153\" \/><\/a> The Zika virus is an enveloped virus transmitted by mosquitoes, especially Aedes aegypti. The range of this mosquito includes much of the United States, from the Southwest and Southeast to as far north as the Mid-Atlantic. The range of A. albopictus, another vector, extends even farther north to New England and parts of the Midwest.[\/caption]\r\n\r\n[h5p id=\"17\"]\r\n<h3><span style=\"color: #1f5c99\"><strong>Neglected Tropical Diseases <span style=\"color: #1f5c99\">(NTDs)<\/span><\/strong><\/span><\/h3>\r\n<span class=\"transcription-time-part\" data-time-start=\"2075.289\" data-time-end=\"2077.074\"><strong>Neglected Tropical Diseases (NTDs)<\/strong> are a group of diseases most prevalent in the tropics, that despite affecting millions of people each year, lack adequate prevention and treatment strategies.\u00a0 <strong>Malaria<\/strong> and <strong>Tuberculosis<\/strong> alone kill 2 million people annually. <\/span>\r\n\r\n<span class=\"transcription-time-part\" data-time-start=\"2075.289\" data-time-end=\"2077.074\">These diseases are called neglected because pharmaceutical companies and governments historically direct little research funding toward them by Western nations, partly because these regions are largely unaffected, which additionally makes these treatments less commercially profitable.\u00a0 Addressing NTDs often also requires significant investment in local infrastructure such as access to clean water, healthy food, sanitation, mosquito netting, work safety conditions, health education and health care access.\u00a0 <\/span>\r\n\r\n<span class=\"transcription-time-part\" data-time-start=\"2075.289\" data-time-end=\"2077.074\">The World Health Organization (WHO) currently prioritizes 18 NTDs, affecting over 1 billion of the world's poorest people.\u00a0 A landmark study found that of more than 1,500 drugs that come to market between 1975 and 2004, only 10 were targeted at NTDs.\u00a0 Approximately 1.4 billion people are currently affected by NTDs.<\/span><span class=\"transcription-time-part\" data-time-start=\"2107.175\" data-time-end=\"2110.099\">\u00a0 <\/span>\r\n\r\n&nbsp;\r\n<div class=\"mceTemp\"><\/div>\r\n\r\n[caption id=\"attachment_227\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-227 size-medium\" title=\"Neglected Tropical Diseases\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-300x204.png\" alt=\"\" width=\"300\" height=\"204\" \/><\/a> The World Health Organization (WHO) prioritizes 18 neglected tropical diseases (NTDs) that affect over a billion of the world\u2019s poorest people and pose a significant economic burden to developing economies.\u00a0 NTDs don\u2019t just affect low- and middle-income countries, although their victims are often socioeconomically disadvantaged. Cysticercosis, echinococcus, toxocariasis, Dengue virus, West Nile virus, and Chagas disease all have appeared in the United States, disproportionately afflicting the poor. Peter Hotez of the Sabin Vaccine Institute and Baylor College of Medicine has estimated that half of the 20 million people living in poverty in the US are infected with at least one NTD. ~Rachel Cotton, Harvard Immunology Program[\/caption]\r\n\r\n<div class=\"textbox textbox--key-takeaways\"><header class=\"textbox__header\">\r\n<p class=\"textbox__title\"><strong>Examples of Neglected Tropical Diseases<\/strong><\/p>\r\n\r\n<\/header>\r\n<div class=\"textbox__content\">\r\n\r\n<strong>Chagas disease:<\/strong>\u00a0 caused by a protozoa carried by an insect vector (triatomine bugs, also known \"kissing bugs\").\r\n\r\n<strong>Dengue fever: <\/strong> caused by virus transmitted through mosquito bites.\r\n\r\n<strong>Leprosy:<\/strong>\u00a0 caused by bacteria in airborne respiratory droplets\r\n\r\n<strong>Helminth infections:<\/strong>\u00a0 caused by tiny parasitic worms (e.g., Guinea-worms) that enter the body through contaminated water (consumed or waded in), through the skin or through contaminated food.\r\n\r\n<\/div>\r\n<\/div>\r\n<h3><span style=\"color: #1f5c99\"><strong>What is Epidemiology?<\/strong><\/span><\/h3>\r\n<span class=\"transcription-time-part\" data-time-start=\"2273.96\" data-time-end=\"2275.669\"><strong>Epidemiology<\/strong><\/span> <span class=\"transcription-time-part\" data-time-start=\"2277.5\" data-time-end=\"2279.389\">is the science of<\/span> <span class=\"transcription-time-part\" data-time-start=\"2279.389\" data-time-end=\"2281.069\">tracking the pattern and<\/span> <span class=\"transcription-time-part\" data-time-start=\"2281.069\" data-time-end=\"2283.2\">the occurrence of disease.<\/span>\u00a0 It is essential for planning effective prevention strategies, efficient use of health care resources, and appropriate training and deployment of health care professionals.\r\n\r\nPrevention strategies typically include:\u00a0 health education, food security, travel advisories, vaccinations, equipping health facilities with appropriate equipment and medications, and public health campaigns (e.g., hygiene strategies during cold and flu season).\r\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\" border=\"0\">\r\n<tbody>\r\n<tr style=\"height: 31px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Communicable<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 31px\">Used interchangeably with <strong>infectious<\/strong> disease.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Notifiable Disease<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">A disease tracked by health authorities because regular and timely information is necessary for planning prevention and control in order to maintain public safety.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Incidence<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 15px\">The number of <strong>new cases<\/strong> of a disease within a population over a given time period.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Prevalence<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">The number of <strong>new plus existing current cases<\/strong> of a disease within a population.\u00a0 Prevalence is always higher than incidence.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n[h5p id=\"18\"]\r\n<h3><span style=\"color: #1f5c99\"><strong>Endemic, Epidemic, and Pandemic<\/strong><\/span><\/h3>\r\nThe <strong>etymology<\/strong> (study of word origins) of these three terms can be helpful in remembering the difference between them.\u00a0 All three share the Greek word <strong>demos<\/strong> meaning 'people'.\r\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 91px\" border=\"0\">\r\n<tbody>\r\n<tr style=\"height: 31px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Endemic<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 31px\">'Endo-' (within) + 'demos' (people):\u00a0 A disease maintained in a population at expected baseline levels without an outside source.\u00a0 Example:\u00a0 cold and flu viruses in Canada, which circulate year-round and peak each winter.<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Epidemic<\/strong><\/span><\/td>\r\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">'Epi-' (above) + 'demos' (people):\u00a0 An outbreak in which a disease occurs at a higher rate than expected within a set population.\u00a0 Example:\u00a0 a year with unexpectedly high flu rates in Canada<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px\">\r\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Pandemic<\/strong><\/span><\/td>\r\n<td style=\"width: 81.7889%;height: 15px\">'Pan-' (all\/global) + 'demos' (people):\u00a0 An infectious disease that has spread across borders or worldwide.\u00a0 Examples include the Spanish flu (1918), H1N1 flu (early 2000s), SARS-CoV1 (2003), and SARS-CoV2 (2019) also known as COVID19.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n[caption id=\"attachment_2283\" align=\"alignnone\" width=\"300\"]<a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG.png\" target=\"_blank\" rel=\"noopener\"><img class=\"wp-image-2283 size-medium\" title=\"Proactive control measure during epidemics\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-300x183.png\" alt=\"Proactive control measures can reduce peak number of cases during epidemics\" width=\"300\" height=\"183\" \/><\/a> Proactive control measures can reduce peak number of cases during epidemics[\/caption]\r\n\r\n[h5p id=\"21\"]\r\n\r\n<strong>Notifiable Diseases in Canada and the Years Notifiable:<\/strong>\r\n\r\n[h5p id=\"19\"]","rendered":"<figure id=\"attachment_6801\" aria-describedby=\"caption-attachment-6801\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-6801 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-300x123.png\" alt=\"Although medical professionals rely heavily on signs and symptoms to diagnose disease and prescribe treatment, many diseases can produce similar signs and symptoms.\" width=\"300\" height=\"123\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-300x123.png 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-1024x420.png 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-768x315.png 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-1536x630.png 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-65x27.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-225x92.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms-350x144.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/signssymptoms.png 1894w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-6801\" class=\"wp-caption-text\">Although medical professionals rely heavily on signs and symptoms to diagnose disease and prescribe treatment, many diseases can produce similar signs and symptoms.<\/figcaption><\/figure>\n<h3><span style=\"color: #1f5c99\"><strong>Diagnosis, Prognosis, Morbidity and <span style=\"color: #1f5c99\">Mortality<\/span><\/strong><\/span><\/h3>\n<p>&nbsp;<\/p>\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\">\n<tbody>\n<tr style=\"height: 31px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Diagnosis<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 31px\">The identification of the disease, disorder, or syndrome.\u00a0 An accurate diagnosis is essential for appropriate treatment and helps in making a prognosis.\u00a0 An accurate diagnosis can depend on the availability of specific tests and medical equipment.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Prognosis<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">The predicted outcome of an illness or injury.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Morbidity<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 15px\">The rate of a particular disease within a population.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Mortality<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">The typical death rate associated with a disease or disorder.<\/td>\n<\/tr>\n<tr>\n<td class=\"border\" style=\"width: 18.2111%\"><span style=\"color: #032c80\"><strong>Etiology<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%\">The study of the cause of a disease, disorder, or syndrome.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3><span style=\"color: #1f5c99\"><strong>Etiology &#8211; Categories of Causes<\/strong><\/span><\/h3>\n<p>The causes of diseases, disorders, and syndromes can be organized into the following categories:<\/p>\n<ul>\n<li><strong>Infectious diseases:<\/strong> caused by viruses, bacteria, fungi, helminths, and protozoa.<\/li>\n<li><strong>Immune dysfunction:<\/strong>\u00a0 illness arising from a deficient or overactive immune system (e.g., allergies, autoimmune diseases).<\/li>\n<li><strong>Trauma:<\/strong>\u00a0 bone fractures, wounds, injuries.<\/li>\n<li><strong>Nutritional deficiencies.<\/strong><\/li>\n<li><strong>Cancer.<\/strong><\/li>\n<li><strong>Lifestyle factors.<\/strong><\/li>\n<li><strong>Toxins.<\/strong><\/li>\n<li><strong>Genetics.<\/strong><\/li>\n<li><strong>Congenital defects.<\/strong><\/li>\n<\/ul>\n<p><span class=\"transcription-time-part\" data-time-start=\"1654.639\" data-time-end=\"1656.649\"><strong>Genetic Disorders, Hereditary Diseases, and Congenital Defects<\/strong><\/span><\/p>\n<p>Three closely related but distinct terms deserve careful attention:<\/p>\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\">\n<tbody>\n<tr style=\"height: 31px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Genetic Disorder<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 31px\">An ailment caused by a<strong> DNA mutation<\/strong>.\u00a0 Mutations can be inherited or occur spontaneously during cell division.\u00a0 Exposure to carcinogenic agent also damages DNA and give rise to cancer.\u00a0 Cancer is therefore an example of a genetic disorder caused specifically by mutations in genes that control cell division (mitosis) and apoptosis.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Hereditary Disease<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">A genetic disease that has been <strong>inherited<\/strong> from a parent (e.g., Hemophilia, resulting from a mutation in a clotting factor gene).<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Congenital Defect<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 15px\">Anatomical or functional defects occurring during embryonic or fetal development, presenting at birth.\u00a0 The word comes from Latin <strong>con-<\/strong> (&#8216;with&#8217;) + <strong>genesis<\/strong> (&#8216;creation of&#8217;).<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Examples of genetic disorders you may be familiar with:<\/p>\n<ul>\n<li><strong>Cystic fibrosis<\/strong>:\u00a0 recessive, caused by a mutation on chromosome 7.<\/li>\n<li><strong>Sickle cell anemia<\/strong>: recessive, caused by a mutation in the hemoglobin beta chain gene on chromosome 11.<\/li>\n<li><strong>Marfan syndrome<\/strong>:\u00a0 autosomal dominant, mutation on chromosome 15.<\/li>\n<li><strong>Huntington&#8217;s disease<\/strong>:\u00a0 autosomal dominant, mutation on chromosome 4.<\/li>\n<li><strong>Down syndrome:<\/strong> inheritance of three copies of chromosome 21 (trisomy 21).<\/li>\n<\/ul>\n<figure id=\"attachment_2220\" aria-describedby=\"caption-attachment-2220\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2220 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-300x226.jpg\" alt=\"Sickle Cell Anemia\" width=\"300\" height=\"226\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-300x226.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-1024x771.jpg 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-768x578.jpg 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-1536x1156.jpg 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-65x49.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-225x169.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12-350x263.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Risk-Factors-for-Sickle-Cell-Anemia_12.jpg 1600w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2220\" class=\"wp-caption-text\">Sickle cell anemia is part of a group of genetic disorders known as sickle cell disease. In those with sickle cell anemia, red blood cells, which are usually round, flexible and flow easily within blood vessels, are sickle-shaped and lead to blockages to blood flow. This sickle shape is caused by an abnormal form of hemoglobin, a protein responsible for carrying oxygen. As a result, less oxygen is delivered to organs of the body, leading to severe consequences, including stroke.<\/figcaption><\/figure>\n<figure id=\"attachment_2221\" aria-describedby=\"caption-attachment-2221\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2221 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-300x208.jpg\" alt=\"Marfan syndrome\" width=\"300\" height=\"208\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-300x208.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-1024x711.jpg 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-768x533.jpg 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-65x45.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-225x156.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_-350x243.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Marfan_wrist.tiff_.jpg 1080w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2221\" class=\"wp-caption-text\">A positive wrist sign in a patient with Marfan syndrome, where the thumb and little finger overlap when grasping the wrist of the opposite hand. Marfan syndrome is a genetic disorder that affects connective tissues (gives support, protection, and structure to other tissues and organs), commonly affecting the heart, eyes, blood vessels and skeleton. Individuals with Marfan syndrome are typically tall and thin, with unusually long arms, legs, and digits.<\/figcaption><\/figure>\n<figure id=\"attachment_2227\" aria-describedby=\"caption-attachment-2227\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2227 size-medium\" title=\"Karyotype\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome-300x186.png\" alt=\"Example of congenital multifactorial defect: down syndrome.\" width=\"300\" height=\"186\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome-300x186.png 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome-65x40.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome-225x139.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome-350x216.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/21_trisomy_-_Down_syndrome.png 718w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2227\" class=\"wp-caption-text\">Karyotype (an individual&#8217;s complete set of chromosomes) of trisomy 21 (Down syndrome), where there is the presence of a third copy of chromosome 21.<\/figcaption><\/figure>\n<p>The most common congenital defects include: <strong> congenital heart defects<\/strong>, <strong>hypospadias<\/strong> <span class=\"transcription-time-part\" data-time-start=\"1728.275\" data-time-end=\"1730.255\">(slight misplacement of urethra within penis)<\/span>, clubfoot (inward turn of foot), <strong>cleft lip<\/strong> and <strong>cleft palate<\/strong> <span class=\"transcription-time-part\" data-time-start=\"1728.275\" data-time-end=\"1730.255\">(incomplete fusion of right and left palatine and\/or maxillae bones in the roof of the mouth)<\/span>, <strong>limb defects<\/strong>, and <strong>mental dysfunction<\/strong>.\u00a0 Many of these can be surgically corrected or managed with physical therapy.<\/p>\n<p>The causes of congenital defects are most often <strong>multifactorial<\/strong> &#8211; meaning many factors are responsible &#8211; including genetic susceptibilities, fetal exposure to <strong>teratogens.<\/strong><\/p>\n<div class=\"textbox textbox--key-takeaways\">\n<header class=\"textbox__header\">\n<p class=\"textbox__title\"><strong>What are Teratogens?<\/strong><\/p>\n<\/header>\n<div class=\"textbox__content\">\n<p>All agents that can cause <strong>congenital defects<\/strong>, <strong>miscarriages,<\/strong> or <strong>stillbirths<\/strong> are grouped together and called <strong>teratogens.<\/strong>\u00a0 These include:\u00a0 various microbes, alcohol, drugs, toxins (e.g., mercury, lead), gamma radiation, x-rays, and nutritional deficiencies.<\/p>\n<p>A growing <strong>embryo<\/strong> and later <strong>fetus<\/strong> are especially susceptible during <strong>organogenesis<\/strong> (the formation of new organs), when teratogens can have the most harmful effects.\u00a0 The severity of congenital defects typically depends on the <strong>timing, duration,<\/strong> and <strong>concentration<\/strong> of teratogen exposure, as well as the fetus&#8217;s genetic composition.<\/p>\n<p>Examples include:\u00a0 <strong>Fetal Alcohol Syndrome<\/strong> (caused by prenatal alcohol exposure), and congenital defects caused by infections such as rubella, <strong>measles, mumps, chlamydia,<\/strong> and <strong>syphilis<\/strong> &#8211; which can cause blindness, deafness, and cognitive delay.<\/p>\n<p><strong>Zika virus<\/strong>, spread by mosquito species in tropical regions (e.g., Uganda, Central America) has been linked to congenital defects including <strong>microcephaly,<\/strong> reduced brain development and cognitive impairments.<\/p>\n<p>The overall risk factors for congenital defects also include maternal health, maternal age, and maternal exposure to cigarette smoke.<\/p>\n<\/div>\n<\/div>\n<figure id=\"attachment_2216\" aria-describedby=\"caption-attachment-2216\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2216 size-medium\" title=\"Mercury contamination is a problem in the Florida Everglades\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-300x225.jpg\" alt=\"Mercury contamination is a problem in the Florida Everglades\" width=\"300\" height=\"225\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-300x225.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-1024x768.jpg 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-768x576.jpg 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-1536x1152.jpg 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-65x49.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-225x169.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury-350x263.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/2048px-Everglades_Mercury.jpg 2048w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2216\" class=\"wp-caption-text\">Mercury contamination is a problem in the Florida Everglades, and in many bodies of water throughout the world (Photo by Tom Friedel). In the Everglades, mercury is supplied via atmospheric deposition, groundwater discharge, and stormwater run-off. Mercury content in the water and fish are so high that swimming or fish consumption should be limited or completely abstained to avoid mercury toxicity.<\/figcaption><\/figure>\n<figure id=\"attachment_2217\" aria-describedby=\"caption-attachment-2217\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2217 size-medium\" title=\"Cutaneous mercury granuloma\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-300x225.jpg\" alt=\"Cutaneous mercury granuloma is a rare disorder caused by the introduction of elemental mercury (Hg) into skin. treat an open wound.\" width=\"300\" height=\"225\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-300x225.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-1024x768.jpg 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-768x576.jpg 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-1536x1152.jpg 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-65x49.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-225x169.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271-350x263.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Mercury_-_Skin_-_42041654271.jpg 2048w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2217\" class=\"wp-caption-text\">Cutaneous mercury granuloma is a rare disorder caused by the introduction of elemental mercury (Hg) into skin (Photo by Y. Rosen). Metallic mercury in tissue appears as black, opaque, spherical globules of varying size. They provoke a granulomatous foreign-body reaction composed of foreign body giant cells, granulomas and a mixed inflammatory infiltrate. The method of introduction could be skin penetration by a mercury-containing object or the use of mercury-containing medication to treat an open wound.<\/figcaption><\/figure>\n<figure id=\"attachment_2218\" aria-describedby=\"caption-attachment-2218\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2218 size-medium\" title=\"United States Environmental Protection Agenc\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1-300x207.jpg\" alt=\"\" width=\"300\" height=\"207\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1-300x207.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1-65x45.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1-225x155.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1-350x242.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/EPA_workers_clean_up_residential_mercury_spill_3986683989-1.jpg 600w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2218\" class=\"wp-caption-text\">United States Environmental Protection Agency (U.S. EPA) emergency response contractors clean up mercury at a Nevada home. Symptoms of mercury poisoning vary depending on exposure dose, duration, method, and type, though symptoms can include kidney and central nervous system damage, or death.<\/figcaption><\/figure>\n<figure id=\"attachment_2223\" aria-describedby=\"caption-attachment-2223\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2223 size-medium\" title=\"Hypospadias\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg-300x163.jpg\" alt=\"Example of congenital multifactorial defect: hypospadias.\" width=\"300\" height=\"163\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg-300x163.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg-65x35.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg-225x122.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg-350x190.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Hypospadias-lg.jpg 600w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2223\" class=\"wp-caption-text\">Hypospadias is a congenital malformation in males, characterized by abnormal fetal development of penis so that the opening of the urethra is located on the underside of the penis rather than the tip. In subcoronal hypospadias, the urethral opening is located just below the head of the penis. In midshaft hypospadias, the urethral opening is located halfway down the underside of the penis. In penoscrotal hypospadias, the urethral opening is located where the shaft of the penis meets the scrotum.<\/figcaption><\/figure>\n<figure id=\"attachment_2228\" aria-describedby=\"caption-attachment-2228\" style=\"width: 225px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2228 size-medium\" title=\"Cleft lift and cleft palate\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate-225x300.png\" alt=\"Example of a congenital multifactorial defect: cleft lip and cleft palate.\" width=\"225\" height=\"300\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate-225x300.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate-65x87.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate-350x467.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Unilateral_and_Bilateral_Cleft_Lip_and_Palate.png 768w\" sizes=\"auto, (max-width: 225px) 100vw, 225px\" \/><\/a><figcaption id=\"caption-attachment-2228\" class=\"wp-caption-text\">Cleft lift and cleft palate are among the most common congenital defects, where parts of the upper lip or palate do not fuse properly in utero. Unilateral cleft lip and\/or palates occur if the defect only occurs on one side, while Bilateral cleft lip and\/or palates occur when the defect is on both sides.<\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<figure id=\"attachment_2224\" aria-describedby=\"caption-attachment-2224\" style=\"width: 212px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2224 size-medium\" title=\"Clubfoot\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot-212x300.jpg\" alt=\"Example of a congenital multifactorial defect: clubfoot\" width=\"212\" height=\"300\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot-212x300.jpg 212w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot-65x92.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot-225x319.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot-350x496.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/813_Clubfoot.jpg 529w\" sizes=\"auto, (max-width: 212px) 100vw, 212px\" \/><\/a><figcaption id=\"caption-attachment-2224\" class=\"wp-caption-text\">Clubfoot, which affects the muscles and bones in the feet, is the most common congenital malformation (occurs in about 0.1% of births). Affected feet (can be only one or both) twist down and rotate inwards.<\/figcaption><\/figure>\n<figure id=\"attachment_2225\" aria-describedby=\"caption-attachment-2225\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2225 size-medium\" title=\"Foot Abduction Brace\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-300x192.jpg\" alt=\"\" width=\"300\" height=\"192\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-300x192.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-1024x656.jpg 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-768x492.jpg 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-1536x983.jpg 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-2048x1311.jpg 2048w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-65x42.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-225x144.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Clubfoot_Foot_Abduction_Brace-scaled-1-350x224.jpg 350w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2225\" class=\"wp-caption-text\">A foot abduction brace consists of two straight-border, high-top, open-toe shoes attached to an aluminum bar, with the heels of the shoes at shoulder distance apart and the shoes themselves set at 60-70 degree angles. This device is used as part of the Ponseti method (a series of casting and orthotic brace treatments) of non-surgically treating young children born with clubfoot.<\/figcaption><\/figure>\n<div id=\"h5p-51\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-51\" class=\"h5p-iframe\" data-content-id=\"51\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Causes of diseases are sometimes arranged in the following categories (at times they fit in more than one category).\u00a0 Can you think of examples of each one?\"><\/iframe><\/div>\n<\/div>\n<h3><span style=\"color: #1f5c99\"><strong>Clinical Manifestations &#8211; Signs and Symptoms<\/strong><\/span><\/h3>\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\">\n<tbody>\n<tr style=\"height: 31px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Clinical Manifestation<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 31px\">A formal term for signs or symptoms<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Sign<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">Observable indicators of illness &#8211; fever, rash, lab test results, imaging results<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Symptom<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 15px\">Indicators of illness that are not observable by another person &#8211; pain, weakness, fatigue, nausea, headache, cramps, sleeplessness.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>&nbsp;<\/p>\n<div id=\"h5p-14\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-14\" class=\"h5p-iframe\" data-content-id=\"14\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Vocabulary Practice\"><\/iframe><\/div>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"textbox textbox--key-takeaways\">\n<header class=\"textbox__header\">\n<p class=\"textbox__title\"><strong>What is a Biopsy?<\/strong><\/p>\n<\/header>\n<div class=\"textbox__content\">\n<p>A <strong>biopsy<\/strong> refers to the excision or scraping of a tissue sample, usually examined under a <strong>microscope<\/strong> for signs of disease.\u00a0 For example, a <strong>Pap smear<\/strong> involves scraping <strong>cervical cells<\/strong> and sending them to a lab where cellular morphology is examined for early signs of cervical cancer.\u00a0 The Pap smear is typically recommended every 2-3 years (as per physician recommendation) after an individual becomes sexually active.\u00a0 Early detection of cervical cancer greatly improves the chance of successful treatment.<\/p>\n<\/div>\n<\/div>\n<h3><span style=\"color: #1f5c99\"><strong>Idiopathic and Iatrogenic Disease<\/strong><\/span><\/h3>\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\">\n<tbody>\n<tr style=\"height: 31px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Idiopathic<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 31px\">A disease of unknown cause.\u00a0 The prefix <strong>idios<\/strong> is Greek for &#8216;one&#8217;s own&#8217;.\u00a0 The synonym <strong>essential<\/strong> is also used (e.g., essential hypertension:\u00a0 high blood pressure not resulting from a medical condition, most often linked to obesity, unhealthy diet, sedentary behaviour and family history.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Iatrogenic<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">A disease caused by the health care practitioner or by the treatment itself.\u00a0 The prefix <strong>iatro<\/strong> is Greek for &#8216;doctor&#8217;.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>&nbsp;<\/p>\n<div id=\"h5p-15\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-15\" class=\"h5p-iframe\" data-content-id=\"15\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"A Canadian Moment:  Pause and Reflect\"><\/iframe><\/div>\n<\/div>\n<h3><span style=\"color: #1f5c99\"><strong>Predisposing Factors (Risk Factors)<\/strong><\/span><\/h3>\n<p><span class=\"transcription-time-part\" data-time-start=\"1908.025\" data-time-end=\"1910.74\">A <strong>predisposing factor<\/strong><\/span> <span class=\"transcription-time-part\" data-time-start=\"1910.74\" data-time-end=\"1913.665\">is another term for risk factor &#8211; a condition or characteristic that increases a person&#8217;s susceptibility to developing a disease.\u00a0 Common risk factors include:<\/span><\/p>\n<ul>\n<li><span class=\"transcription-time-part\" data-time-start=\"1913.665\" data-time-end=\"1915.869\"><strong>Age<\/strong>:\u00a0 Older age increases risk for cancer and many other diseases, as a lifetime of exposure to damaging agents accumulates and cells become less effective at providing protection, fighting infection and healing tissue. <\/span><\/li>\n<li><span class=\"transcription-time-part\" data-time-start=\"1919.559\" data-time-end=\"1921.675\"><strong>Biological sex<\/strong>: Females are more susceptible to autoimmune diseases and lung cancer.\u00a0 Males are more susceptible to cardiovascular disease, X-linked colour blindness, <\/span><span class=\"transcription-time-part\" data-time-start=\"1923.609\" data-time-end=\"1925.934\">and Duchenne muscular dystrophy.<\/span><\/li>\n<li><span class=\"transcription-time-part\" data-time-start=\"1925.934\" data-time-end=\"1928.095\"><strong>Genetics<\/strong>:\u00a0 Certain genetic profiles increase susceptibility (e.g., sickle cell anemia, cystic fibrosis)<\/span><span class=\"transcription-time-part\" data-time-start=\"1936.089\" data-time-end=\"1937.234\">.<\/span><\/li>\n<li><strong>Congenital defects<\/strong>:\u00a0 Some defects (e.g., congenital heart defects) can make organs less robust and more susceptible to wear and tear, injury and disease.<\/li>\n<li><span class=\"transcription-time-part\" data-time-start=\"1937.234\" data-time-end=\"1939.43\"><strong>Diet<\/strong>:\u00a0 Malnutrition impairs growth, cognitive function, and organ function globally.\u00a0 In many Western countries, diets high in fat, sugar, and\/or salt increase risk for heart disease, diabetes, and possibly <\/span>Alzheimer&#8217;s disease.<\/li>\n<li><span class=\"transcription-time-part\" data-time-start=\"1950.65\" data-time-end=\"1952.899\"><strong>Occupation<\/strong>:\u00a0 Exposure to radiation, asbestos coal dust, and pollutants, increases risk for cancers and lung disease.\u00a0 Pesticide use is being linked to the onset of Parkinson&#8217;s disease.<\/span><\/li>\n<li><span class=\"transcription-time-part\" data-time-start=\"2031.859\" data-time-end=\"2034.65\"><strong>Location<\/strong><\/span>:\u00a0 Geography determines exposure to local infectious microbes, sociodemographic factors, and cultural practices.\u00a0 For example, malaria is endemic to tropical regions where the Plasmodium protozoan parasite is carried by specific mosquitoes.<\/li>\n<\/ul>\n<figure id=\"attachment_2199\" aria-describedby=\"caption-attachment-2199\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria.jpg\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2199 size-medium\" title=\"RBCs infected with Plasmodium falciparum\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-300x238.jpg\" alt=\"Example of relapse\" width=\"300\" height=\"238\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-300x238.jpg 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-1024x811.jpg 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-768x609.jpg 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-1536x1217.jpg 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-65x52.jpg 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-225x178.jpg 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria-350x277.jpg 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/Red_blood_cells_infected_with_malaria.jpg 1551w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2199\" class=\"wp-caption-text\">Electron micrograph of red blood cells infected with Plasmodium falciparum, the parasite that causes malaria in humans. Patients with malaria often exhibit a relapse of symptoms following a peak of symptoms and, occasionally, long periods of dormancy.<\/figcaption><\/figure>\n<figure id=\"attachment_6799\" aria-describedby=\"caption-attachment-6799\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-6799 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-300x128.png\" alt=\"Blood smears showing two diseases of the blood. (a) Malaria is an infectious, zoonotic disease caused by the protozoan pathogen Plasmodium falciparum (shown here) and several other species of the genus Plasmodium. It is transmitted by mosquitoes to humans. (b) Sickle cell disease is a noninfectious genetic disorder that results in abnormally shaped red blood cells, which can stick together and obstruct the flow of blood through the circulatory system. It is not caused by a pathogen, but rather a genetic mutation.\" width=\"300\" height=\"128\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-300x128.png 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-1024x436.png 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-768x327.png 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-1536x655.png 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-65x28.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-225x96.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle-350x149.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/Malaria-and-Sickle.png 1875w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-6799\" class=\"wp-caption-text\">Blood smears showing two diseases of the blood. (a) Malaria is an infectious, zoonotic disease caused by the protozoan pathogen Plasmodium falciparum (shown here) and several other species of the genus Plasmodium. It is transmitted by mosquitoes to humans. (b) Sickle cell disease is a noninfectious genetic disorder that results in abnormally shaped red blood cells, which can stick together and obstruct the flow of blood through the circulatory system. It is not caused by a pathogen, but rather a genetic mutation.<\/figcaption><\/figure>\n<figure id=\"attachment_6803\" aria-describedby=\"caption-attachment-6803\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-6803 size-medium\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-300x153.png\" alt=\"The Zika virus is an enveloped virus transmitted by mosquitoes, especially Aedes aegypti. The range of this mosquito includes much of the United States, from the Southwest and Southeast to as far north as the Mid-Atlantic. The range of A. albopictus, another vector, extends even farther north to New England and parts of the Midwest.\" width=\"300\" height=\"153\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-300x153.png 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-1024x524.png 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-768x393.png 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-1536x786.png 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-65x33.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-225x115.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika-350x179.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2026\/06\/zika.png 1656w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-6803\" class=\"wp-caption-text\">The Zika virus is an enveloped virus transmitted by mosquitoes, especially Aedes aegypti. The range of this mosquito includes much of the United States, from the Southwest and Southeast to as far north as the Mid-Atlantic. The range of A. albopictus, another vector, extends even farther north to New England and parts of the Midwest.<\/figcaption><\/figure>\n<div id=\"h5p-17\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-17\" class=\"h5p-iframe\" data-content-id=\"17\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"World Maps of Disease and Injury\"><\/iframe><\/div>\n<\/div>\n<h3><span style=\"color: #1f5c99\"><strong>Neglected Tropical Diseases <span style=\"color: #1f5c99\">(NTDs)<\/span><\/strong><\/span><\/h3>\n<p><span class=\"transcription-time-part\" data-time-start=\"2075.289\" data-time-end=\"2077.074\"><strong>Neglected Tropical Diseases (NTDs)<\/strong> are a group of diseases most prevalent in the tropics, that despite affecting millions of people each year, lack adequate prevention and treatment strategies.\u00a0 <strong>Malaria<\/strong> and <strong>Tuberculosis<\/strong> alone kill 2 million people annually. <\/span><\/p>\n<p><span class=\"transcription-time-part\" data-time-start=\"2075.289\" data-time-end=\"2077.074\">These diseases are called neglected because pharmaceutical companies and governments historically direct little research funding toward them by Western nations, partly because these regions are largely unaffected, which additionally makes these treatments less commercially profitable.\u00a0 Addressing NTDs often also requires significant investment in local infrastructure such as access to clean water, healthy food, sanitation, mosquito netting, work safety conditions, health education and health care access.\u00a0 <\/span><\/p>\n<p><span class=\"transcription-time-part\" data-time-start=\"2075.289\" data-time-end=\"2077.074\">The World Health Organization (WHO) currently prioritizes 18 NTDs, affecting over 1 billion of the world&#8217;s poorest people.\u00a0 A landmark study found that of more than 1,500 drugs that come to market between 1975 and 2004, only 10 were targeted at NTDs.\u00a0 Approximately 1.4 billion people are currently affected by NTDs.<\/span><span class=\"transcription-time-part\" data-time-start=\"2107.175\" data-time-end=\"2110.099\">\u00a0 <\/span><\/p>\n<p>&nbsp;<\/p>\n<div class=\"mceTemp\"><\/div>\n<figure id=\"attachment_227\" aria-describedby=\"caption-attachment-227\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-227 size-medium\" title=\"Neglected Tropical Diseases\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-300x204.png\" alt=\"\" width=\"300\" height=\"204\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-300x204.png 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-1024x695.png 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-768x521.png 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-65x44.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-225x153.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy-350x237.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2023\/06\/Neglected-Tropical-Diseases-copy.png 1101w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-227\" class=\"wp-caption-text\">The World Health Organization (WHO) prioritizes 18 neglected tropical diseases (NTDs) that affect over a billion of the world\u2019s poorest people and pose a significant economic burden to developing economies.\u00a0 NTDs don\u2019t just affect low- and middle-income countries, although their victims are often socioeconomically disadvantaged. Cysticercosis, echinococcus, toxocariasis, Dengue virus, West Nile virus, and Chagas disease all have appeared in the United States, disproportionately afflicting the poor. Peter Hotez of the Sabin Vaccine Institute and Baylor College of Medicine has estimated that half of the 20 million people living in poverty in the US are infected with at least one NTD. ~Rachel Cotton, Harvard Immunology Program<\/figcaption><\/figure>\n<div class=\"textbox textbox--key-takeaways\">\n<header class=\"textbox__header\">\n<p class=\"textbox__title\"><strong>Examples of Neglected Tropical Diseases<\/strong><\/p>\n<\/header>\n<div class=\"textbox__content\">\n<p><strong>Chagas disease:<\/strong>\u00a0 caused by a protozoa carried by an insect vector (triatomine bugs, also known &#8220;kissing bugs&#8221;).<\/p>\n<p><strong>Dengue fever: <\/strong> caused by virus transmitted through mosquito bites.<\/p>\n<p><strong>Leprosy:<\/strong>\u00a0 caused by bacteria in airborne respiratory droplets<\/p>\n<p><strong>Helminth infections:<\/strong>\u00a0 caused by tiny parasitic worms (e.g., Guinea-worms) that enter the body through contaminated water (consumed or waded in), through the skin or through contaminated food.<\/p>\n<\/div>\n<\/div>\n<h3><span style=\"color: #1f5c99\"><strong>What is Epidemiology?<\/strong><\/span><\/h3>\n<p><span class=\"transcription-time-part\" data-time-start=\"2273.96\" data-time-end=\"2275.669\"><strong>Epidemiology<\/strong><\/span> <span class=\"transcription-time-part\" data-time-start=\"2277.5\" data-time-end=\"2279.389\">is the science of<\/span> <span class=\"transcription-time-part\" data-time-start=\"2279.389\" data-time-end=\"2281.069\">tracking the pattern and<\/span> <span class=\"transcription-time-part\" data-time-start=\"2281.069\" data-time-end=\"2283.2\">the occurrence of disease.<\/span>\u00a0 It is essential for planning effective prevention strategies, efficient use of health care resources, and appropriate training and deployment of health care professionals.<\/p>\n<p>Prevention strategies typically include:\u00a0 health education, food security, travel advisories, vaccinations, equipping health facilities with appropriate equipment and medications, and public health campaigns (e.g., hygiene strategies during cold and flu season).<\/p>\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 76px\">\n<tbody>\n<tr style=\"height: 31px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Communicable<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 31px\">Used interchangeably with <strong>infectious<\/strong> disease.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Notifiable Disease<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">A disease tracked by health authorities because regular and timely information is necessary for planning prevention and control in order to maintain public safety.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Incidence<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 15px\">The number of <strong>new cases<\/strong> of a disease within a population over a given time period.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Prevalence<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">The number of <strong>new plus existing current cases<\/strong> of a disease within a population.\u00a0 Prevalence is always higher than incidence.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div id=\"h5p-18\">\n<div class=\"h5p-content\" data-content-id=\"18\"><\/div>\n<\/div>\n<h3><span style=\"color: #1f5c99\"><strong>Endemic, Epidemic, and Pandemic<\/strong><\/span><\/h3>\n<p>The <strong>etymology<\/strong> (study of word origins) of these three terms can be helpful in remembering the difference between them.\u00a0 All three share the Greek word <strong>demos<\/strong> meaning &#8216;people&#8217;.<\/p>\n<table class=\"grid landscape\" style=\"border-collapse: collapse;width: 100%;height: 91px\">\n<tbody>\n<tr style=\"height: 31px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 31px\"><span style=\"color: #032c80\"><strong>Endemic<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 31px\">&#8216;Endo-&#8216; (within) + &#8216;demos&#8217; (people):\u00a0 A disease maintained in a population at expected baseline levels without an outside source.\u00a0 Example:\u00a0 cold and flu viruses in Canada, which circulate year-round and peak each winter.<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"shaded\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Epidemic<\/strong><\/span><\/td>\n<td class=\"shaded\" style=\"width: 81.7889%;height: 15px\">&#8216;Epi-&#8216; (above) + &#8216;demos&#8217; (people):\u00a0 An outbreak in which a disease occurs at a higher rate than expected within a set population.\u00a0 Example:\u00a0 a year with unexpectedly high flu rates in Canada<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td class=\"border\" style=\"width: 18.2111%;height: 15px\"><span style=\"color: #032c80\"><strong>Pandemic<\/strong><\/span><\/td>\n<td style=\"width: 81.7889%;height: 15px\">&#8216;Pan-&#8216; (all\/global) + &#8216;demos&#8217; (people):\u00a0 An infectious disease that has spread across borders or worldwide.\u00a0 Examples include the Spanish flu (1918), H1N1 flu (early 2000s), SARS-CoV1 (2003), and SARS-CoV2 (2019) also known as COVID19.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<figure id=\"attachment_2283\" aria-describedby=\"caption-attachment-2283\" style=\"width: 300px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG.png\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2283 size-medium\" title=\"Proactive control measure during epidemics\" src=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-300x183.png\" alt=\"Proactive control measures can reduce peak number of cases during epidemics\" width=\"300\" height=\"183\" srcset=\"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-300x183.png 300w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-1024x623.png 1024w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-768x467.png 768w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-1536x934.png 1536w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-65x40.png 65w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-225x137.png 225w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG-350x213.png 350w, https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-content\/uploads\/sites\/1961\/2024\/09\/SlowTheSpread_whiteBG.png 1726w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-2283\" class=\"wp-caption-text\">Proactive control measures can reduce peak number of cases during epidemics<\/figcaption><\/figure>\n<div id=\"h5p-21\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-21\" class=\"h5p-iframe\" data-content-id=\"21\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Patient Medical History\"><\/iframe><\/div>\n<\/div>\n<p><strong>Notifiable Diseases in Canada and the Years Notifiable:<\/strong><\/p>\n<div id=\"h5p-19\">\n<div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-19\" class=\"h5p-iframe\" data-content-id=\"19\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Notifiable Diseases in Canada\"><\/iframe><\/div>\n<\/div>\n<div class=\"media-attributions clear\" prefix:cc=\"http:\/\/creativecommons.org\/ns#\" prefix:dc=\"http:\/\/purl.org\/dc\/terms\/\"><h2>Media Attributions<\/h2><ul><li about=\"https:\/\/openstax.org\/books\/microbiology\/pages\/15-introduction\"><a rel=\"cc:attributionURL\" href=\"https:\/\/openstax.org\/books\/microbiology\/pages\/15-introduction\" property=\"dc:title\">signssymptoms<\/a>  &copy;  Nina Parker, Mark Schneegurt, Anh-Hue Thi Tu, Philip Lister, Brian M. Forster (Image credit left: modification of work by U.S. Navy)    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA (Attribution NonCommercial ShareAlike)<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:Risk-Factors-for-Sickle-Cell-Anemia_(1)2.jpg\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Risk-Factors-for-Sickle-Cell-Anemia_(1)2.jpg\" property=\"dc:title\">Private: Sickle Cell Anemia<\/a>  &copy;  Diana Grib    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/\">CC BY-SA (Attribution ShareAlike)<\/a> license<\/li><li about=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/24165013\/\"><a rel=\"cc:attributionURL\" href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/24165013\/\" property=\"dc:title\">Private: Marfan_wrist.tiff<\/a>  &copy;  Staufenbiel I, Hauschild C, Kahl-Nieke B, Vahle-Hinz E, von Kodolitsch Y, Berner M, Bauss O, Geurtsen W, and Rahman A    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/\">CC BY-SA (Attribution ShareAlike)<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:21_trisomy_-_Down_syndrome.png\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:21_trisomy_-_Down_syndrome.png\" property=\"dc:title\">Private: 21_trisomy_-_Down_syndrome<\/a>  &copy;  U.S. Department of Energy Human Genome Program    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/publicdomain\/mark\/1.0\/\">Public Domain<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:Everglades_Mercury.jpg\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Everglades_Mercury.jpg\" property=\"dc:title\">Private: 2048px-Everglades_Mercury<\/a>  &copy;  <a rel=\"dc:creator\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Tomfriedel\" property=\"cc:attributionName\">Tom Friedel<\/a>    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY (Attribution)<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:Mercury_-_Skin_-_42041654271.jpg\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Mercury_-_Skin_-_42041654271.jpg\" property=\"dc:title\">Private: Mercury_-_Skin_-_42041654271<\/a>  &copy;  Y. Rosen, MD    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/\">CC BY-SA (Attribution ShareAlike)<\/a> license<\/li><li about=\"https:\/\/www.flickr.com\/people\/24400159@N05\"><a rel=\"cc:attributionURL\" href=\"https:\/\/www.flickr.com\/people\/24400159@N05\" property=\"dc:title\">Private: EPA_workers_clean_up_residential_mercury_spill_3986683989-1<\/a>  &copy;  <a rel=\"dc:creator\" href=\"https:\/\/www.flickr.com\/people\/24400159@N05\" property=\"cc:attributionName\">USEPA Environmental Protection Agency<\/a>    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/publicdomain\/mark\/1.0\/\">Public Domain<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:Hypospadias-lg.jpg\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Hypospadias-lg.jpg\" property=\"dc:title\">Private: Hypospadias-lg<\/a>  &copy;  Centers for Disease Control and Prevention    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/publicdomain\/mark\/1.0\/\">Public Domain<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:Unilateral_and_Bilateral_Cleft_Lip_and_Palate.png\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Unilateral_and_Bilateral_Cleft_Lip_and_Palate.png\" property=\"dc:title\">Private: Unilateral_and_Bilateral_Cleft_Lip_and_Palate<\/a>  &copy;  <a rel=\"dc:creator\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:BruceBlaus\" property=\"cc:attributionName\">Bruce Blaus<\/a>    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/\">CC BY-SA (Attribution ShareAlike)<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:813_Clubfoot.jpg\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:813_Clubfoot.jpg\" property=\"dc:title\">Private: 813_Clubfoot<\/a>  &copy;  OpenStax College    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY (Attribution)<\/a> license<\/li><li about=\"https:\/\/commons.wikimedia.org\/wiki\/File:Clubfoot_Foot_Abduction_Brace.jpg\"><a rel=\"cc:attributionURL\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Clubfoot_Foot_Abduction_Brace.jpg\" property=\"dc:title\">Private: Clubfoot Foot Abduction Brace<\/a>  &copy;  Bassgrab75    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/\">CC BY-SA (Attribution ShareAlike)<\/a> license<\/li><li about=\"https:\/\/www.flickr.com\/photos\/nihgov\/25534997493\/in\/photolist-EUrx8t-CvR53a-B3Ad52-ydGygr-wZzPff-C5BN5H\"><a rel=\"cc:attributionURL\" href=\"https:\/\/www.flickr.com\/photos\/nihgov\/25534997493\/in\/photolist-EUrx8t-CvR53a-B3Ad52-ydGygr-wZzPff-C5BN5H\" property=\"dc:title\">Private: Red_blood_cells_infected_with_malaria<\/a>  &copy;  Rick Fairhurst and Jordan Zuspann, National Institute of Allergy and Infectious Diseases, National Institutes of Health    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/publicdomain\/mark\/1.0\/\">Public Domain<\/a> license<\/li><li about=\"https:\/\/openstax.org\/books\/microbiology\/pages\/15-1-characteristics-of-infectious-disease\"><a rel=\"cc:attributionURL\" href=\"https:\/\/openstax.org\/books\/microbiology\/pages\/15-1-characteristics-of-infectious-disease\" property=\"dc:title\">Malaria and Sickle<\/a>  &copy;  Nina Parker, Mark Schneegurt, Anh-Hue Thi Tu, Philip Lister, Brian M. Forster (Image (credit a: modification of work by Centers for Disease Control and Prevention; credit b: modification of work by Ed Uthman)    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA (Attribution NonCommercial ShareAlike)<\/a> license<\/li><li about=\"https:\/\/openstax.org\/books\/microbiology\/pages\/16-3-modes-of-disease-transmission\"><a rel=\"cc:attributionURL\" href=\"https:\/\/openstax.org\/books\/microbiology\/pages\/16-3-modes-of-disease-transmission\" property=\"dc:title\">zika<\/a>  &copy;  Nina Parker, Mark Schneegurt, Anh-Hue Thi Tu, Philip Lister, Brian M. Forster (Image credit micrograph: modification of work by Cynthia Goldsmith, Centers for Disease Control and Prevention; credit photo: modification of work by James Gathany, Centers for Disease Control and Prevention; credit map: modification of work by Centers for Disease Control and Prevention)    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA (Attribution NonCommercial ShareAlike)<\/a> license<\/li><li about=\"https:\/\/sitn.hms.harvard.edu\/flash\/special-edition-on-infectious-disease\/2014\/neglected-tropical-diseases-progress-and-challenges-for-the-post-2015-development-era\/\"><a rel=\"cc:attributionURL\" href=\"https:\/\/sitn.hms.harvard.edu\/flash\/special-edition-on-infectious-disease\/2014\/neglected-tropical-diseases-progress-and-challenges-for-the-post-2015-development-era\/\" property=\"dc:title\">Neglected Tropical Diseases<\/a>  &copy;  Rachel Cotton    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA (Attribution NonCommercial ShareAlike)<\/a> license<\/li><li about=\"http:\/\/ctbergstrom.com\/covid19.html\"><a rel=\"cc:attributionURL\" href=\"http:\/\/ctbergstrom.com\/covid19.html\" property=\"dc:title\">Private: SlowTheSpread_whiteBG<\/a>  &copy;  <a rel=\"dc:creator\" href=\"http:\/\/ctbergstrom.com\/index.html\" property=\"cc:attributionName\">Esther Kim & Carl T. Bergstrom<\/a>    is licensed under a  <a rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY (Attribution)<\/a> license<\/li><\/ul><\/div>","protected":false},"author":1370,"menu_order":4,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":["zoe-soon"],"pb_section_license":"cc-by-nc-sa"},"chapter-type":[],"contributor":[60],"license":[57],"class_list":["post-6255","chapter","type-chapter","status-web-only","hentry","contributor-zoe-soon","license-cc-by-nc-sa"],"part":3,"_links":{"self":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/6255","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/users\/1370"}],"version-history":[{"count":12,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/6255\/revisions"}],"predecessor-version":[{"id":6804,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/6255\/revisions\/6804"}],"part":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapters\/6255\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/media?parent=6255"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/pressbooks\/v2\/chapter-type?post=6255"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/contributor?post=6255"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/pathophysiology\/wp-json\/wp\/v2\/license?post=6255"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}