Schistosomiasis

Schistosomiasis, also known as snail fever or bilharzia, is a parasitic disease caused by several species of flatworms belonging to the genus Schistosoma. Freshwater snails release larval forms of the parasite.

These parasites infect humans and other mammals, leading to a range of health issues. Schistosomiasis is a significant global health concern, particularly in regions with poor sanitation and limited access to clean water.

People can be infected with schistosomiasis when they swim or fish in freshwater contaminated with Schistosoma parasites.

The parasites penetrate human skin and enter the bloodstream, then mature into microscopic adult worms and reproduce in the veins surrounding organs. This usually occurs in the intestines or bladder.

The parasite stays in the human body. The transmission cycle continues when someone suffering from schistosomiasis expels urine or faeces into freshwater sources. Their excreta contains parasite eggs, which then hatch in the water.

Schistosomiasis is prevalent in tropical and subtropical regions, particularly in Africa, South America, the Middle East, and parts of Asia.

While people of all ages can be affected, the disease is most common in children and young adults whose daily activities bring them into contact with contaminated water. Travellers to endemic areas can also contract the disease.

The symptoms of schistosomiasis vary depending on the parasite species and stage of infection. Symptoms can include:

• fever
• rash
• cough
• muscle aches
• abdominal pain
• diarrhoea
• blood in the urine
• organ damage (particularly liver and kidneys).

Schistosomiasis is commonly found in tropical or subtropical regions, with freshwater snail species that allow the parasites to complete their life cycle.

It is not found in Australia, but travellers to endemic areas should take precautions to prevent infection.

The treatment of schistosomiasis typically involves anti-parasitic drugs such as praziquantel. These medications are effective in killing adult parasites and are usually administered under medical supervision.

However, early diagnosis and treatment are crucial to prevent the disease progressing or leading to complications. In endemic regions, controlling the disease also relies on public health measures, such as improving sanitation and access to clean water, and educating people about how to prevent infection.