Seasonal variation of hepatitis B and C virus infection among HIV- and non-HIV-infected patients in Benin City, Nigeria

Introduction
Seasonal variation in immunity has been found in healthy individuals and in association with some diseases. Data on seasonal prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection is sparse. This study aimed at determining the seasonal seroprevalence of HBV and HCV infections among human immunodeficiency virus (HIV)-infected patients in Benin City.

Material and methods
A total of 1,177 HIV-positive and 503 non-HIV-positive patients were recruited for this study. Venous blood was collected from all participants and screened for the presence of HBsAg and anti-HCV antibody using immunochromatographic technique.

Results
The seroprevalence of HBV infection did not differ significantly with respect to season among HIV-infected patients (rainy season vs. dry season: 4.2% vs. 3.4%; OR = 1.271; 95% CI = 0.695-2.322; p = 0.451), and non-HIV-infected patients (rainy season vs. dry season: 3.2% vs. 4.0%; OR = 0.783; 95% CI = 0.305-2.020; p = 0.639). A statistically significant association was however observed between HCV seropositivity and rainy season among HIV-infected patients only (rainy season vs. dry season: 3.9% vs. 1.1%; OR = 3.789, 95% CI = 1.537-9.342; p = 0.003).

Conclusions
HIV-infected patients in Nigeria are at risk of acquiring HCV infection during the rainy season. Control and prevention methods for HBV and HCV infections among HIV-infected patients are advocated.