Paediatric Schistosomiasis: indirect, long-term impacts on health - Wellcome Trust

Abstract

Schistosomiasis commonly known as bilharzia or snail fever affects around 240 million people worldwide with a further 600 million people at risk of infection. While over 90% of the cases occur in Africa, schistosomiasis is also an emerging problem in Europe with a recent foci discovered in Corsica in France and is also a significant risk for people travelling to endemic areas and taking part in water-related activities. There are 3 main species affecting humans, Schistosoma mansoni, S. japonicum and S. haematobium with the first two species causing the intestinal schistosomiasis and the last species causing the urogenital form of the disease. Our group, the Parasite Immunoepidemiology Group at the University of Edinburgh, working with colleagues at the University of Zimbabwe and Ministry of Health in Zimbabwe through our research program the ‘Understanding Bilharzia Program’, have focused on urogenital schistosomiasis with the classic symptom of excreting blood in urine (haematuria). Through our collaborative work, we have been able to implement 5-year national schistosomiasis control program in Zimbabwe targeting primary school children aged 6 years and above from 2012. Our current focus is now on the younger children, aged 5 years and below.When a young child in the western world excretes blood in their urine, the child is quite rightly, immediately rushed to A&E and attended to – this is what happened to the index case (a 4-year old) at the new foci in France. In contrast, several millions of African children live with this condition for decades while the pathology is worsening and this is not being treated with the same level of urgency. This condition can be treated with a single dose of the antihelminthic drug, Praziquantel. This drug is safe and efficacious, with cure rates as high as 100% in some areas and is given as a single oral dose. Our recent work has focused on the treatment of young children though building the evidence base for the inclusion of preschool children (aged 5 years and below) in national schistosome treatment programs though Mass Drug Administration (MDA) and developing operational tools for their treatment. This goal is now within sight, with the World Health Organisation’s recommendations in 2010 that these children should be treated for schistosomiasis and the private-public partnership, the Paediatric Praziquantel Consortium developing a paediatric formulation of Praziquantel, now awaiting Phase III clinical trials. Our own research group is currently investigating the most optimal time to treat these preschool children, relative to time of infection in terms of morbidity control and facilitation of the development of acquired immunity protective against re-infection. Making the best use of the tools we already have against schistosomiasis, including optimal antihelminthic treatment, improved water and sanitation and education while developing additional complementary interventions (e.g. snail control and vaccine) will help in controlling a disease that is a major public health concern.