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Human genetic resistance to malaria. Human genetic resistance to malaria refers to inherited changes in the DNA of humans which increase resistance to malaria and result in increased survival of individuals with those genetic changes. The existence of these genotypes is likely due to evolutionary pressure exerted by parasites of the genus ...
Virgin soil epidemic. A 16th-century illustration of Nahuas infected with smallpox. In epidemiology, a virgin soil epidemic is an epidemic in which populations that previously were in isolation from a pathogen are immunologically unprepared upon contact with the novel pathogen. [1] Virgin soil epidemics have occurred with European settlement ...
Most people became infected during their lifetimes, and about 30% of people infected with smallpox died from the disease, presenting a severe selection pressure on the resistant survivors. [ 26 ] In northern Japan, Ainu population decreased drastically in the 19th century, due in large part to infectious diseases like smallpox brought by ...
Innate resistance to HIV. A small proportion of humans show partial or apparently complete innate resistance to HIV, the virus that causes AIDS. [1] The main mechanism is a mutation of the gene encoding CCR5, which acts as a co-receptor for HIV. It is estimated that the proportion of people with some form of resistance to HIV is under 10%.
Humans probably came into contact with these rodents, and some people became infected by the viruses they carried. When viruses cross this so-called "species barrier", their effects can be severe, [6] and humans may have had little natural resistance. Contemporary humans lived in small communities, and those who succumbed to infection either ...
Cholera outbreaks were more devastating primarily because indigenous communities had little forms of water filtration and lacked immunity to water-borne diseases. [94] Due to a lack of immunity to water-borne disease, Native Americans suffered from higher mortality rates [95] Lack of immunity and exposure to bodies of water contaminated by ...
Race and health refers to how being identified with a specific race influences health. Race is a complex concept that has changed across chronological eras and depends on both self-identification and social recognition. [1] In the study of race and health, scientists organize people in racial categories depending on different factors such as ...
The 2009 swine flu pandemic, caused by the H1N1/swine flu/influenza virus and declared by the World Health Organization (WHO) from June 2009 to August 2010, was the third recent flu pandemic involving the H1N1 virus (the first being the 1918–1920 Spanish flu pandemic and the second being the 1977 Russian flu). [12][13] The first identified ...