West Africa: Bolstering Early Warning Disease Detection
Communities across West Africa continue to face old and new infectious disease threats, including waterborne diseases like cholera and typhoid, viral hemorrhagic fevers like Ebola, Lassa fever and yellow fever, and new emerging threats like mpox.
The region also faces more frequent public health crises due to extreme weather events, rapid urbanization, displacement and high rates of antimicrobial resistance – all of which can help fuel the spread of infectious disease.
In response, health officials, policymakers and health financing partners, including the Global Fund, are working to strengthen disease control capacities by replicating a best practice surveillance model from within the region – Senegal’s Sentinel Syndromic Surveillance System – known as the 4S Network.
Established more than a decade ago, the 4S Network is an early warning disease surveillance system established by the Institut Pasteur de Dakar and the Ministry of Health.
The network now operates through 38 sentinel sites based in clinics and hospitals across the country. At these sites, case-based data on the number of patients presenting with symptoms such as fever, cough and diarrhea are registered on a daily basis and shared with health authorities in real-time via a data management platform – allowing officials to detect emerging health threats early and respond rapidly if needed.
Through the West African Regional Laboratory Initiative, the Global Fund is working to build upon the 4S model by establishing similar surveillance activities across West Africa. To date, the Global Fund has enabled 4S activities to begin in Benin, Guinea Bissau, Sierra Leone and Togo, with plans to include Burkina Faso in 2026.
The Gates Foundation and the Africa CDC collaborated with national authorities to set up sentinel surveillance sites in Cabo Verde, The Gambia, Guinea, Mali, Mauritania and Niger.
Investments made in expanding the network have already proved their worth, detecting numerous viral pathogens including dengue, chikungunya, Crimean Congo hemorrhagic virus and yellow fever – allowing authorities to act rapidly.