At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.
Bilharzia or schistosomiasis is a parasitic infection caused when humans come into contact with schistosomes, which are types of worms that are normally carried by certain types of snails. Contact usually occurs in fresh water sources, and no ingestion is necessary. Instead, the worms may invade the skin and travel to other parts of the body, causing significant illness.
It is important to note that bilharzia doesn’t occur in all parts of the world. People who are likely to acquire this parasitic infection live in or travel to places like parts of Asia, South America, the Middle East, Africa, or some of the Caribbean islands. Schistosomiasis is not likely to occur in North America or most of Europe, usually due to more comprehensive sanitation methods and cooler climates.
After bilharzia infection occurs, it may become serious. When worms enter the body, they begin to lay eggs, and these hatched eggs travel to other parts of the body. Infection can spread to the spleen, the lungs, the bladder, kidneys, liver, and sometimes to the brain.
Symptoms of bilharzia are very different than many other traveler’s parasitic infections. Most people first notice a skin rash, but many won’t show symptoms until a few months after exposure. As worms spread through the body, many systems could be affected, but primarily some people experience flulike symptoms with fever and achiness. This could be followed by diarrhea if worms are in the intestines, and others might note bloody urine as a principal symptom. Where the worms are present in the body makes a difference in what symptoms emerge.
Some people go for years with untreated bilharzia, and the parasite can continue to invade the body. This is when it is likely that it will begin to have an impact on major organs and it might cause things such as impaired breathing or seizures. To avoid this scenario, it’s important to catch early symptoms, particularly if they have followed any bathing, wading or swimming in fresh water in one of the identified areas listed above.
Schistosomiasis is imminently treatable with medications like praziquantel. Greater support could be needed if the infection is of long duration and damage has occurred in major organs. Most medical experts agree that treatment is important, but prevention is even more useful.
When traveling to areas far from home, bathing in fresh water, whether lakes or rivers, isn’t recommended. Some areas assure safety of water by treating it with substances that will kill snails and worms, but it’s generally better to be safe than sorry. The no swimming rule is an unfortunate one because many tropical areas have beautiful lakes that are extremely inviting. Given the possible consequences, though, staying out of the water, and only choosing ocean water to swim in, makes better sense.
In areas where sanitation creates this issue, the only potential cure is improving it. Often, when bilharzia occurs regularly in native populations, sanitation efforts are still not at peak efficiency. This is frequently due to poverty and inability to fund such efforts.