by Assunta Uffer-Marcolongo, President of IAMAT

Are you planning a safari to Kenya or an adventure travel expedition to Brazil? If so, you could be at risk of schistosomiasis.

Like other neglected tropical diseases, schistosomiasis (also known as bilharziasis) is also a threat to travelers. More than 200 million people are infected with schistosomiasis mainly in tropical and subtropical rural areas, particularly children and young adultss

Schistosomiasis is caused by different types of Schistosoma blood flukes (flatworms) which can enter the intact human skin when swimming in fresh water: ponds, lakes, and rivers, or coming into contact with infected water. It is a disease found mainly in rural areas with poor sanitation and lack of proper human waste disposal facilities.

Both snails and humans are needed to complete the parasite’s life-cycle. In contaminated water, the flukes are shed – in the form of larva or cercariae – by snails that live on aquatic plants. They penetrate through your skin and migrate to the intestines or bladder where they grow into adult flatworms.

Flatworms can remain in the human body for long periods of time – even decades – mate, and produce thousands of eggs. The eggs migrate through the intestinal or bladder walls to be excreted in feces or urine. If discharged into an open body of water, the eggs enter the snail hosts to restart the cycle. Since the infection can be seasonal or localized, any fresh water in countries or areas reporting schistosomiasis must be considered infected. If untreated, schistosomiasis can damage the intestines and bladder, cause chronic abdominal bleeding, as well as liver or kidney disease.

IAMAT provides schistosomiasis prevention advice to travelers, including information on the life-cycle of the parasite causing ‘snail fever’ and the detailed geographic distribution of the infection. See  IAMAT’s World Schistosomiasis Risk Chart and Be Aware of Schistosomiasis which are also available on www.iamat.org.

Ten Tips for Prevention When Traveling to an Infected Area:
1. If you are planning a trip into the jungle or desert, make sure it is a short one, so that you can withstand the heat and are not tempted to cool off in a pond or stream. Make sure you do not run out of purified water.

2. If you must pass through streams or swamps, wear high waterproof boots or hip waders.

3. Stay away from the banks of streams and rivers; snails abound in shallow water where they feed on organic waste and aquatic vegetation. Snail presence is minimal in the center of rivers and streams where the water flow is faster.

4. Avoid contact with fresh water during peak daylight hours when the cercariae emerge from the snails and are most active.

5. If you accidentally come into contact with fresh water, rub your skin immediately with rubbing alcohol and a dry towel to reduce the possibility of infection.

6. If you are travelling overland by car, carry a pair of rubber gloves in case you have to dip your hands into a stream or pond to get water for the radiator.

7. Water from a river or lake used for bathing and washing should be boiled or chlorinated.

8. Water for washing and bathing is relatively safe if it has been stored for 2-3 days (the period generally accepted as the life span of cercariae), provided that the container is free of snails.

9. Drinking water should be boiled for 10 minutes or treated with chlorine tablets, as the cercariae may burrow through the mucosa of the mouth.

10. Make sure vegetables are well cooked and avoid salads since the leaves may have been washed with infected water.

Assunta Uffer-Marcolongo is IAMAT’s President. IAMAT (International Association for Medical Assistance to Travellers) is a non-profit organization dedicated to travel health. As an advocate for travellers’ health, IAMAT has provided comprehensive health information on immunizations, illness and disease risks, and food and water safety precautions for all countries since 1960. The organization also coordinates an international  network of doctors and mental health practitioners for travellers in need of emergency care during their journey. Since 2002, IAMAT has awarded scholarships and grants to doctors and nurses from developing countries to study and train in the field of travel medicine.