Schistosomiasis, or bilharzia, is a parasitic disease caused by trematode flatworms. Larval forms of the parasites, which are released by freshwater snails, penetrate the skin of people in the water. the body, the larvae develop into adult schistosomes, which live in the blood vessels of the infected person. The females release eggs, some of which are passed out of the body in the urine or faeces.
Schistosomiasis is contracted through the skin from fresh water contaminated with urine or faeces of an infected person. Aside from Malaria, it is the most common health problem in tropical and sub tropical areas affecting around 200 million people.
Travellers might experience an irritable, itchy rash develop a few hours after contact, where the larvae enter the body. Some people can remain symptom free for several weeks, until the egg of the larvae hatch and then a fever can occur. One of 5 types of fluke cause an infection of the bladder and/or bowel, often with bleeding as a side effect. Recently, there have been concerning reports of paralysis within the legs after infection.
Who is at risk Schistosomiasis?Any travellers visiting an area deemed as at risk of transmission, are vulnerable to contraction of the infection. This includes South America, Africa and parts of the Middle East and India, and in Asia. Caution should be taken with diving lessons in fresh water lakes in risk areas, and is advisable to avoid altogether.
How can I prevent Schistosomiasis?There is currently no vaccine to protect against Schistosomiasis. However, travellers can take some preventative measures to protect themselves as much as possible. It is advisable to avoid swimming or paddling in fresh water lakes, streams, and rivers. Since the larvae need water to survive, a quick drying method after being in water may help to offer some protection. Minimal protection is also gained from wearing rubber boots or wet suits