Cases of dengue were documented in the African continent as early as 1823 and the infection has since been reported in 34 African countries, where Aedes sp are present. But the burden of disease in the continent is unclear, and the reported case numbers are unlikely to represent true infection rates. And yet very few population-based studies have been conducted to verify the incidence, compared to Asia and the Americas.

Collecting new data on the occurrence of dengue and conducting seroprevalence studies in Africa would therefore be extremely useful in improving estimates of the virus burden on the continent. DNDi aims to assess the dengue burden in the continent, allowing for informed, cost-effective decision-making on the use of new prevention tools such as vaccines and vector control strategies, as well as future treatments.

As part of this assessment, known as ‘SERODEN’, DNDi and partners will undertake a retrospective dengue seroprevalence study in Senegal and in selected cities in Ghana (Accra, Kumasi, and Tamale) and the DRC (Kinshasa and Matadi). The seropositivity to the four dengue serotypes and other circulating arboviruses (Zika, yellow fever, chikungunya, West Nile, O’nyong-nyong and Usutu virus) will also be quantified by multiplex immunoassay.

A second element of this project is to update the global burden of dengue, including new estimates from the surveys in Africa and other estimates generated after literature review. The impact of implementing new control strategies will be modelled under various deployment scenarios. New control strategies will be considered including dengue vaccination, vector control strategies with the release of Wolbachia-infected mosquitoes, and potentially other interventions (e.g. use of antiviral treatments).

Project update