It occurs only in areas where a particular aquatic snail species is native, which the parasites need for their development. The snail lives on banks of standing or slow-flowing freshwaters. Distribution areas are mainly Africa, the east of Central and South America and isolated areas in Asia.
The pathogens penetrate the skin through contact with contaminated freshwater, i.e., bathing, washing, wading through a stream, or fishing. Larvae are also ingested by drinking contaminated water. Six to 48 hours after entry of the parasites, a skin rash with severe itching occurs. After two weeks, chills, fever, cough and headache follow. If left untreated, the flukes infect the intestines and bladder and cause permanent discomfort. Schistosomiasis heals without problems, provided it is treated in time with the anthelmintic praziquantel.
In summary, here are the most important tips:
- There is a risk of infection especially when bathing in stagnant waters with embankments, not at stony waterfalls in the mountains.
- Couple flukes reproduce only in fresh water.
