Infections
Medicines for Schistosomiasis
A parasitic infection caught from contaminated fresh water in parts of Africa and elsewhere — treatable, and important for travellers who swim in affected lakes and rivers.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Schistosomiasis?
Schistosomiasis (bilharzia) is an infection caused by parasitic worms (schistosomes) that live in certain freshwater snails. People catch it by coming into contact with contaminated fresh water — such as swimming, wading, or washing in affected lakes, rivers and streams — where the parasite penetrates the skin.
- How it is treated: Schistosomiasis is treated effectively with a specific anti-parasitic medicine (praziquantel), which kills the adult worms; treatment is usually well tolerated and often given in a short course, sometimes repeated.
- Self-care: When travelling in affected regions, avoid swimming, wading or washing in fresh water (lakes, rivers, streams) — the main way to prevent schistosomiasis, as there is no vaccine.
- When to seek help: See a doctor or travel clinic if you have had fresh-water contact in an affected area (such as swimming in a lake in Africa), even without symptoms, so testing can be arranged.
What it is
Schistosomiasis (bilharzia) is an infection caused by parasitic worms (schistosomes) that live in certain freshwater snails. People catch it by coming into contact with contaminated fresh water — such as swimming, wading, or washing in affected lakes, rivers and streams — where the parasite penetrates the skin. It is common in parts of Africa, and also occurs in the Middle East, parts of Asia, South America and the Caribbean, but not from the sea or chlorinated pools. In the UK it is seen in travellers and migrants from affected areas. Soon after exposure, some people get an itchy rash ("swimmer's itch") where the parasite entered, and weeks later a feverish illness can occur. Over the longer term, the worms can cause inflammation and damage in the organs where they settle — commonly the bladder and urinary system (causing blood in the urine) or the bowel and liver — which is why it is important to diagnose and treat, even in people with few symptoms. It is diagnosed with blood, urine or stool tests.
How it is treated
Schistosomiasis is treated effectively with a specific anti-parasitic medicine (praziquantel), which kills the adult worms; treatment is usually well tolerated and often given in a short course, sometimes repeated. Because the medicine works on the adult worms, timing of treatment and follow-up testing may be considered, and specialist advice is often sought, particularly for travellers. Treating the infection prevents the long-term organ damage that untreated schistosomiasis can cause. Anyone who has had fresh-water contact in an affected area — even without symptoms — may be advised to be tested, as the infection can be silent while still causing harm over time. Prevention for travellers is important: avoiding swimming, wading or washing in fresh water in affected regions is the main protection, as there is no vaccine. The reassuring message is that schistosomiasis is treatable, and testing after fresh-water exposure in affected areas allows it to be caught and treated before it causes lasting harm.
For this condition, these medicines
Medicine classes used for Schistosomiasis
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Beyond medication
Lifestyle and self-care
When travelling in affected regions, avoid swimming, wading or washing in fresh water (lakes, rivers, streams) — the main way to prevent schistosomiasis, as there is no vaccine. After any fresh-water contact in these areas, consider being tested even without symptoms.
When to get help
When to see a doctor
See a doctor or travel clinic if you have had fresh-water contact in an affected area (such as swimming in a lake in Africa), even without symptoms, so testing can be arranged. Seek assessment for blood in the urine, tummy or bowel symptoms, or a feverish illness after such travel.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Schistosomiasis: frequently asked questions
How do you catch schistosomiasis (bilharzia)?
By contact with contaminated fresh water — such as swimming, wading or washing in affected lakes, rivers or streams (common in parts of Africa and elsewhere), where the parasite penetrates the skin. Not from the sea or chlorinated pools.
Is schistosomiasis treatable?
Yes — it is treated effectively with a specific anti-parasitic medicine (praziquantel). Treating it prevents the long-term organ damage that untreated infection can cause, which is why testing after fresh-water exposure in affected areas is worthwhile.
Sources
Where this is drawn from
- NHS — Schistosomiasis (bilharzia)
- TravelHealthPro guidance
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