Contagious diseaseA contagious disease is an infectious disease that is readily spread (that is, communicated) by transmission of a pathogen through contact (direct or indirect) with an infected person. A disease is often known to be contagious before medical science discovers its causative agent. Koch's postulates, which were published at the end of the 19th century, were the standard for the next 100 years or more, especially with diseases caused by bacteria. Microbial pathogenesis attempts to account for diseases caused by a virus.
SyndemicA syndemic or synergistic epidemic is the aggregation of two or more concurrent or sequential epidemics or disease clusters in a population with biological interactions, which exacerbate the prognosis and burden of disease. The term was developed by Merrill Singer in the early 1990s to call attention to the synergistic nature of the health and social problems facing the poor and underserved.
Case fatality rateIn epidemiology, case fatality rate (CFR) – or sometimes more accurately case-fatality risk – is the proportion of people diagnosed with a certain disease, who end up dying of it. Unlike a disease's mortality rate, the CFR does not take into account the time period between disease onset and death. A CFR is generally expressed as a percentage. It represents a measure of disease lethality and may change with different treatments. CFRs are most often used for with discrete, limited-time courses, such as acute infections.
Epidemic typhusEpidemic typhus, also known as louse-borne typhus, is a form of typhus so named because the disease often causes epidemics following wars and natural disasters where civil life is disrupted. Epidemic typhus is spread to people through contact with infected body lice, in contrast to endemic typhus which is usually transmitted by fleas. Though typhus has been responsible for millions of deaths throughout history, it is still considered a rare disease that occurs mainly in populations that suffer unhygienic extreme overcrowding.
Pieter Bruegel the ElderPieter Bruegel (also Brueghel or Breughel) the Elder (ˈbrɔɪɡəl, ˈbruːɡəl; ˈpitər ˈbrøːɣəl; 1525–1530 – 9 September 1569) was the most significant artist of Dutch and Flemish Renaissance painting, a painter and printmaker, known for his landscapes and peasant scenes (so-called genre painting); he was a pioneer in making both types of subject the focus in large paintings. He was a formative influence on Dutch Golden Age painting and later painting in general in his innovative choices of subject matter, as one of the first generation of artists to grow up when religious subjects had ceased to be the natural subject matter of painting.
BuboA bubo (Greek βουβών, boubṓn, 'groin') is adenitis or inflammation of the lymph nodes and is an example of reactive lymphadenopathy. Buboes are a symptom of bubonic plague and occur as painful swellings in the thighs, neck, groin or armpits. They are caused by Yersinia pestis bacteria spreading from flea bites through the bloodstream to the lymph nodes, where the bacteria replicate, causing the nodes to swell. Plague buboes may turn black and necrotic, rotting away the surrounding tissue, or they may rupture, discharging large amounts of pus.
