Entamoeba histolytica

Transmission from person to person is mostly faecal-oral through mature quadranuclear cysts excreted in the stool, either directly (e.g. contaminated hands) or indirectly (e.g. contaminated towels, flannels, food, drinking water ect.). In the outside world, these cysts can retain their infectivity for several weeks under moist conditions (e.g. in sewage). Pathogen transmission is also possible through anal-oral sexual practices. In endemic areas (tropical and subtropical regions with poor hygienic conditions), faecal-contaminated food plants and contaminated drinking water play a major role in transmission.

The symptoms of the disease usually begin insidiously and often develop slowly over 1-3 weeks. At first, there is a feeling of pressure, mild abdominal pain, nausea and diarrhoea alternating with formed stools. The mucus and blood inclusions are initially insignificant, later more intense, whereby glassy or typical raspberry jelly-like mucus deposits then become pathognomic (clearly characteristic of a disease). Pappy to watery, not infrequently bloody-mucous stools occur. Diarrhoea and abdominal pain are frequent symptoms of amoebic dysentery. Fever occurs in only about one third of those affected.

The incubation period varies greatly. A period of a few days up to several months, in individual cases even up to several years can be considered. As a rule, however, the incubation period is 2-4 weeks.

So far, no vaccine is available. Prophylactic medication is not recommended. In endemic areas, avoid eating unwashed fruit and vegetables, drinking water should always be boiled. Pay attention to good hand hygiene. In case of severe diarrhoea and vomiting, it is particularly important to compensate for the loss of fluids and salt.