Schistosomiasis: Causes, Symptoms, and Prevention

Schistosomiasis, also known as snail fever, is a serious parasitic disease that affects internal organs but is preventable. The condition develops when parasitic worms enter the body through skin contact with contaminated freshwater.

Although schistosomiasis does not occur naturally in Canada, it remains highly relevant for Canadians who travel, work, volunteer, or provide humanitarian aid in tropical and subtropical regions where the disease is common. Awareness and early recognition are essential components of international health safety and first aid education.

How Schistosomiasis Develops

Schistosomiasis is caused by parasitic worms (cercariae) that live in freshwater snails. These parasites are released into lakes, ponds, canals, and streams.

Infection occurs when:

• Skin comes into contact with contaminated freshwater

• Water touches exposed skin or lips (not through drinking)

The disease spreads when infected individuals urinate or defecate in freshwater sources. The parasite eggs enter snails, multiply, and are released back into the water, continuing the cycle.

Once the parasites penetrate the skin, they migrate through the bloodstream and mature into adult worms over several weeks. The adult worms release eggs that damage internal organs, especially the bladder, liver, intestines, and lungs.

Who Is Most at Risk?

Schistosomiasis primarily affects individuals who:

• Live in areas without access to safe water

• Bathe, wash clothes, or work in freshwater sources

• Travel to endemic regions and swim or wade in lakes or rivers

⚠️ The disease occurs only in freshwater, not saltwater.

Signs and Symptoms of Schistosomiasis

Symptoms vary depending on the stage of infection. Some individuals may not experience symptoms early on.

Early Symptoms (Days After Exposure)

• Itchy skin

• Rash at the site of water exposure

Later Symptoms (Weeks to Months)

• Fever and chills

• Muscle aches

• Diarrhea

• Cough

• Abdominal pain

• Painful urination

• Blood in urine or stool

• Enlarged liver or spleen

Without treatment, long-term complications can include bladder cancer, liver scarring, intestinal damage, and lung disease.

Management and Treatment

Schistosomiasis is treated with the antiparasitic medication praziquantel. Treatment is highly effective when started early.

Early diagnosis and treatment:

• Prevent long-term organ damage

• Improve recovery outcomes

• Reduce complications

The prognosis is generally very good when treatment occurs before permanent internal damage develops.

Prevention Tips for Canadians Travelling Abroad

• Avoid swimming or wading in freshwater in endemic regions

• Use safe, treated water for bathing

• Dry skin vigorously if accidental exposure occurs

• Follow travel health advisories from Canadian health authorities

Important Disclaimer

Educational Use Only
This content is intended for health awareness and first aid education in Canada. It does not replace professional medical diagnosis or treatment. Anyone exposed to freshwater in regions where schistosomiasis is present should seek medical evaluation.