Schistosomiasis: What it is, how you catch it, and what to do

Schistosomiasis is a parasitic infection you pick up from freshwater where certain snails live. Tiny worm larvae released by those snails can burrow through your skin when you swim, wade, or wash in lakes, rivers, or slow streams. Once inside, they mature and live in blood vessels, sometimes causing serious damage over months or years.

Symptoms vary by stage. Right after exposure you may notice a red, itchy spot where the larvae entered. Weeks later you can get fever, cough, belly pain, diarrhea, or muscle aches. Chronic infections may cause blood in urine, problems peeing, liver enlargement, intestinal pain, or even growth and learning delays in kids. Which symptoms show up depends on the Schistosoma species and how long the worms have been in your body.

How doctors find and treat it

Diagnosis is usually done by testing stool or urine for parasite eggs. If eggs aren’t detected, blood tests can look for antibodies or parasite antigens. Ultrasound or other imaging helps when organs like the liver or bladder look affected. Always tell your clinician about recent travel and any freshwater contact — that makes the right tests more likely.

Treatment is simple in most cases. Praziquantel is the standard drug and usually given in a single-day or two-day course. It kills adult worms. Side effects are mostly mild: nausea, headache, or dizziness as parasites die off. Severe or long-standing cases may need follow-up, repeat treatment, or care for complications like liver scarring or bladder disease.

Practical prevention tips

Avoid freshwater in known schistosomiasis areas. If you travel to parts of Africa, South America, the Middle East, or Asia where cases occur, skip swimming in lakes and slow rivers. If you accidentally enter freshwater, dry your skin quickly and change clothes. Wearing sandals helps prevent cuts but won’t stop larvae from penetrating skin in water.

Community measures work too: snail control, better sanitation, and safe water supplies reduce transmission. There’s no vaccine right now, so prevention depends on behavior and public health actions. For travelers, check country health advice before you go and see a travel clinic about risks.

When to see a doctor? Get tested if you have fever, persistent cough, tummy pain, or blood in urine after freshwater exposure. Pregnant women and children should get medical advice — treatment is possible but needs professional guidance. Quick testing and treatment lower the chance of long-term harm.

If you want, I can point you to trusted health sources, maps of risk areas, or simple checklists for travelers. Tell me where you’re going or what symptoms you’re seeing, and I’ll help you figure out the next steps.