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Epidemiology

Infection is by the fecal-oral route. Direct infection can take place in circumstances of extreme crowding among children, as well as inmates of institutions for the mentally retarded and insane, and among male homosexuals.

Indirect spread, however, by fecal con­tamination of food and water, is more common. Water­borne epidemics of amebic dysentery are not so fre­quent as those Ofbacillary dysentery, but the former do occur when sewage contaminates wells or water pipes. Fruits and vegetables can become covered with cysts when human feces are used as fertilizer, or when fruits are washed in contaminated water or are handled by a symptomatic or asymptomatic carrier. Flies and cockroaches can mechanically transmit cysts from feces to food. The disease thus flourishes in poor sanitary conditions but is rare where good per­sonal hygiene is practiced and where water and sewer systems function properly. Dogs, cats, and mon­keys can be infected in the laboratory, but there is no evidence that animal reservoirs have an epidemiolog­ical significance.

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Source: Kiple Kenneth F. (Editor). The Cambridge World History of Human Disease. Cambridge University Press,1993. — 1200 p.. 1993

More on the topic Epidemiology:

  1. Bibliography
  2. Conclusions
  3. Communicable Diseases