Skip to main content


Click to enlarge

This parasitic disease contracted in fresh water affected 218 million people in 2015

An infestation of the parasites that cause schistosomiasis can last up to eight years and may permanently damage the bladder, kidneys, bowel and genital tract. The parasite’s larvae enter via the skin and reproduce in the veins around the bowels and bladder.

How can I avoid schistosomiasis?

When visiting a place where schistosomiasis is endemic you can avoid it completely by not swimming in fresh water. Sea water and chlorinated water is safe.

The parasites that cause schistosomiasis are similar to the parasites that cause swimmer’s itch – but the larvae that cause swimmer’s itch do not parasitize humans, so they die off rather than migrating through the body. Read more about swimmer’s itch on My Health Alberta.

To avoid schistosomiasis completely, you should not swim or shower in fresh, untreated water (such as rivers and lakes) in regions where schistosomiasis is endemic. Poor sanitation increases the risk of schistosomiasis transmission.

Check before you travel whether you are visiting a place where schistosomiasis occurs. When you come for your appointment at Canadian Travel Clinics for your travel jabs in Red Deer, our specialist nurses will warn you if there is a risk of contracting schistosomiasis at your destination.

Where might I catch schistosomiasis?

There are two types of schistosomiasis. Intestinal schistosomiasis occurs in:

  • Africa
  • the Middle East
  • the Caribbean
  • Brazil, Venezuela and Suriname
  • China, Indonesia, the Philippines, parts of Cambodia and the Lao People’s Democratic Republic

Urogenital schistosomiasis occurs in Africa, the Middle East and Corsica.

What are the symptoms of schistosomiasis

The World Health Organization says that an infestation of schistosomiasis worms is not life-threatening for most healthy people – it is more of a problem for people who live in countries where schistosomiasis is endemic because they may get repeated infections.

Urogenital schistosomiasis manifests as blood in the urine. Intestinal schistosomiasis will result in diarrhea, belly ache, blood in the stools and tiredness. Women may experience gynecological symptoms such as spotting, cramps, pain and bleeding.

If you have been in to a country where schistosomiasis occurs, and you have these symptoms, go and see your usual healthcare provider and let them know about your travel history.

I think I have schistosomiasis

You will have to wait until eight weeks after exposure to get tested. Visit your healthcare provider, describe your travel history and ask for a schistosomiasis assessment. You may have to give stool, urine or blood sample for testing.

Schistosomiasis is treated with a drug called praziquantel. It is best to avoid treatments bought over the counter abroad: they may be counterfeit, and if the dose is not taken at the right time, it will not be effective.

How is schistosomiasis transmitted?

The eggs of the schistosomes are excreted by an infected person and where sanitation is poor, the eggs end up in a freshwater source where they hatch. The larvae find a particular species of snail, which acts as a host. The larvae acquire tails and swim off looking for a human host. They enter through the skin, shedding their tails, and migrate to the blood vessels around the bladder or intestines where they mature, mate and lay eggs, which are excreted via urine or feces.