This requires contact with water, such as swimming in otherwise pristine tropical ponds, lagoons, and slow-moving rivers. Fast-moving streams are free of this parasite. Symptoms vary widely from the lack of symptoms altogether to skin eruptions, fever, back or abdominal pain, bloody stools or urine, and enlargement of the liver and spleen. Complications may include kidney failure and cirrhosis. Praziquantel and oxamniquine are the drugs of choice for killing these parasitic worms.
Cholera is a severe and highly contagious gastro-intestinal malady that causes acute diarrhea.
Mortality is moderate for untreated victims, where death results from dehydration. The best protection against contracting cholera is to drink only pure water and to ensure that vegetables are well washed. With a little bit of forethought it is possible for both the transient Osa traveler as well as the long-term Osa resident to protect themselves from contracting a waterborne disease. A few simple rules come to mind. Never drink unpurified or unfiltered water from a stream or other waterway anywhere in the world.