What is Bilharzia?
Schistosomiasis (bilharzia) is a neglected tropical disease caused by parasitic worms found in contaminated freshwater. It affects millions across the developing world.
- Infected
- 200M+
- At Risk
- 700M+
- Countries
- 78
- Sub-Saharan Africa
- 90%
Understanding the Disease
Bilharzia, also known as schistosomiasis, is a parasitic disease caused by flatworms of the genus Schistosoma. The parasites are released by freshwater snails and penetrate the skin of people who come into contact with contaminated water.
The disease spreads through contaminated freshwater sources such as lakes, rivers, and ponds. When people wade, swim, bathe, or wash in infested water, the parasitic larvae burrow through the skin and mature inside the body.
Symptoms include abdominal pain, diarrhea, blood in urine or stool, and chronic fatigue. In long-term cases, the disease can cause severe liver and kidney damage, impairing growth and cognitive development in children.
Who's At Risk?
- Children playing in contaminated water sources
- Farmers who work in irrigated fields
- Fishermen exposed to infested water daily
- Women doing laundry in rivers and lakes
- Communities without access to clean water and sanitation
Bilharzia in Rwanda
Rwanda's numerous lakes and wetlands create high-risk zones for bilharzia transmission. Communities living near Lake Kivu, Lake Muhazi, and other water bodies are particularly vulnerable to infection.
Children who swim, bathe, or play in infested waters are at the greatest risk. Many families depend on these water sources for their daily needs, from drinking and cooking to farming and fishing.
Without access to clean water and proper sanitation, the cycle of infection continues generation after generation. Breaking this cycle requires a combination of treatment, prevention, education, and infrastructure development.
Frequently Asked Questions
Common questions about bilharzia and how it affects communities.
Bilharzia is contracted through skin contact with freshwater that contains parasitic larvae released by infected snails. Activities like swimming, bathing, fishing, and washing clothes in contaminated lakes and rivers put people at risk. The larvae penetrate the skin within minutes of exposure.
Yes. Praziquantel is a safe, effective, and affordable medication that can treat bilharzia. A single dose is usually sufficient. However, reinfection is common if people continue to be exposed to contaminated water. That is why prevention and clean water access are just as important as treatment.
Neglected tropical diseases (NTDs) are a group of infections that primarily affect the poorest communities and receive relatively little attention in terms of research funding, drug development, and public health investment. Bilharzia affects over 200 million people, yet many have never heard of it.
Chronic bilharzia can cause severe damage to the liver, kidneys, bladder, and intestines. In children, it leads to malnutrition, stunted growth, and impaired cognitive development. In severe cases, it can be fatal. The disease traps families in cycles of poverty by reducing the ability to work and learn.
Prevention involves avoiding contact with contaminated water, improving access to clean water and sanitation, treating infected individuals, and controlling snail populations in water sources. Community education about the disease and its transmission is also critical.
No. Bilharzia cannot spread directly from person to person. It requires freshwater snails as an intermediate host. However, when infected individuals urinate or defecate in freshwater, their eggs hatch and infect snails, which then release larvae that can infect other people.
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