Epidemiology and seroprevalence of Hepatitis E Virus in Nigeria and its African context: a review and one health perspective.

Hepatitis E virus (HEV) is an under-recognised cause of acute viral hepatitis and remains a major public health concern in Africa. Worldwide, over 20 million HEV infections and nearly 3 million symptomatic cases occur annually, but the true extent in Africa is poorly understood due to limited surveillance, inconsistent diagnostics, gaps in blood safety, unclear zoonotic routes, low public awareness, and underreporting. Outbreaks in several African countries are often associated with floods, displacement, and poor sanitation. Seroprevalence studies show notable variation, from less than 1% in Tanzania to over 80% in Egypt, reflecting diverse epidemiological situations across the continent. In Nigeria, two major outbreaks have been reported, with evidence of widespread human exposure and high infection rates in pigs. Addressing these issues requires a One Health approach that integrates human, veterinary, and environmental health systems. Priority interventions include expanding affordable diagnostics, strengthening Water, Sanitation and Hygiene (WASH) infrastructure, routine animal and blood donor screening, targeted education for high-risk groups, and investment in molecular epidemiology. Therefore, this review consolidates current knowledge of HEV in Africa, with insights from Nigeria, and provides recommendations for control through a coordinated One Health approach.