9. Neglected Parasitic Infections and the Syndemic Anemia Vaccines for Africa

Today, malaria, schistosomiasis, and human hookworm infection comprise three of the most common parasitic diseases on the African continent. These neglected parasitic infections also represent important threats to maternal–child health in sub-Saharan Africa, particularly because they cause profound anemia. Malaria, schistosomiasis, and hookworm infection each cause severe anemia, but they are also co-endemic or syndemic and produce additive effects when occurring simultaneously in a single individual, especially a child or pregnant woman. In young children, the combined anemia from these parasitic infections can lead to permanent neurologic deficits, while in pregnant women they are linked to high maternal morbidity and mortality and decreased infant survival. While mass treatments for malaria, schistosomiasis, and human hookworm infection have led to some reductions in maternal–child morbidities in Africa, it is unlikely this approach alone will remain sustainable due to high rates of post-treatment reinfections and other factors, including variable efficacies of the currently available drugs, as well as the prospect of emerging resistance. As complementary or synergistic approaches, there are ongoing efforts to develop vaccines for malaria, human hookworm infection, and schistosomiasis. These biotechnologies would represent innovative approaches to reducing or halting maternal–child health anemia in Africa. Mosquirix is the first malaria vaccine licensed for Africa, while vaccines for schistosomiasis and human hookworm infection are each entering their proof of concept for efficacy in phase 2 clinical trials. New public–private strategic alliances, including the one formed between Merck and Baylor College of Medicine and its international vaccine product development partnership (PDP), the Texas Children’s Hospital Center for Vaccine Development (Texas Children’s CVD), to advance the schistosomiasis vaccine, will be essential to help accelerate vaccine research and development for neglected and emerging infections. These types of partnerships will also require innovative financial instruments to address traditional market failures, allowing licensing and the introduction of anti-parasitic disease vaccines for Africa.