Schistosomiasis

CAPTION: This boy receives Praziquantel to treat his schistosomiasis

In 2008, Sabin’s Vaccine Development Program expanded its efforts to include research and development on a vaccine to prevent the spread of schistosomiasis, a deadly parasitic disease affecting more than 200 million people in 74 countries worldwide, with the greatest number of cases in Africa and Brazil. Schistosomiasis is second only to malaria as the most common parasitic disease in the world, and is also the most deadly, killing approximately 280,000 people annually.

Schistosomiasis is a parasite carried by snails and is transmitted by contact with contaminated fresh water sources such as lakes, ponds, rivers and dams. Schistosomiasis infection is readily transmissible for those who come in frequent contact with contaminated water – particularly children who wade or play in water and women conducting domestic chores. Once inside the body, schistosomiasis larvae develop into adult worms which can live inside the blood vessels for years causing severe blood loss, anemia and malnutrition. Long-term schistosomiasis infections can also cause severe kidney, spleen and liver damage and bladder cancer. Re-infection with contaminated water sources is a major concern in endemic areas of Africa, where chronic schistosomiasis infections are the primary culprit for anemia, impaired growth and poor school performance in children. Pregnant and lactating women infected with schistosomiasis are generally not considered candidates for treatment with the current drug therapies available to help control infection and as a result, often develop severe anemia and are at an increased risk of maternal death. In addition, they are at an increased risk of developing the more severe symptoms of the disease including kidney damage and bladder cancer.