Schistosomiasis
Advancing a schistosomiasis vaccine for Africa, in Africa
Schistosomiasis, a poverty-associated disease caused by parasitic worms, spreads when people come into contact with infested waters during work-related and recreational activities.
Schistosomiasis is a major global public health problem, with the highest disease burden in sub-Saharan Africa. The disease is a significant cause of morbidity for an estimated 200 million people, with an additional 779 million individuals at risk for infection, according to disease burden estimates. Schistosomiasis is the second deadliest disease caused by parasites after malaria, killing more than 200,000 people annually in sub-Saharan Africa alone. The highest disease burden is in school-aged children.
Why a vaccine?
In addition to sustained drug treatment programs, effectively controlling schistosomiasis calls for a proven vaccine
Currently, disease control relies primarily on taking the anti-worm drug praziquantel to treat infection. However, praziquantel does not completely eliminate the parasite and re-infection after treatment is common, making repeated treatment necessary and mass treatment programs unsustainable.
Reducing the number of snail hosts through extermination programs is another option, but it is challenging, labor-intensive, and costly.
A safe, effective, and widely accessible vaccine that can prevent and/or treat schistosomiasis would save countless lives and relieve significant social and economic burdens for millions of people who live in affected regions. There are currently a number of schistosomiasis vaccine candidates in development, but none have been licensed yet.
What is IVI doing?
Advancing clinical development of a promising vaccine candidate
The International Vaccine Institute is leading the development of a safe and effective vaccine through the Vaccine Against Schistosomiasis for Africa (VASA) project, a collaboration through a consortium of ten research institutes around the world and advancing the Sm-p80/GLA-SE (SchistoShield®) vaccine candidate developed by Prof. Afzal Siddiqui.
The VASA project has four key objectives:
- Understanding the current disease burden in Madagascar and Burkina Faso—two schistosomiasis-endemic countries—as well as earliest age of exposure to Schistosoma to inform future vaccine roll-out policies.
- Understanding the financial burden of schistosomiasis on local populations with a cost-of-illness study and estimating the cost-effectiveness of a vaccine.
- A controlled human infection model study.
- A phase 1b clinical trial in Burkina Faso and Madagascar to assess the safety and reactogenicity of the SchistoShield® vaccine, one of the leading schistosomiasis vaccine candidates.
The next stage of VASA, funded by the Gates Foundation, has one objective:
- A phase 2a clinical trial of SchistoShield® vaccine in Madagascar.
IVI’s Schistosomiasis in Madagascar (SOMA) project in collaboration with the University of Antananarivo launched in 2018 with the aim of reducing the intensity and prevalence of schistosomiasis infection for at-risk populations in the Ambositra District of Madagascar.
Throughout the project, over 100,000 people were treated with the anti-worm drug praziquantel through a mass drug administration campaign while water, sanitation, and hygiene education and training programs were held in schools and at community gatherings. The SOMA project oversaw the construction of two cisterns, 20 toilets, and two shower facilities across primary and secondary schools, public markets, and health care centers to increase access to sanitation and hygiene practices.
Page updated: March 2025