Underreporting of Hepatitis E virus infection in Tanzania: a systematic review

Introduction: Hepatitis E virus (HEV) frequently causes acute hepatitis with water-borne outbreaks in endemic areas. Updated evidence is required in Tanzania to inform the policymakers and identify research gaps.Objective: The aim of this study was to analyse publications on the epidemiology of HEV in Tanzania.Methods: We systematically searched all available publications from the major research databases, and selected websites for unindexed studies, policies, and reports for data reporting on the epidemiology of HEV in Tanzania from inception to date.Results: Five articles were found. There was only one study, performed in 1998, that reported the prevalence of HEV infection in the general  Tanzanian population (0.2%). Three other studies reported prevalence’s of 8%, 6.6% and 0% among HIV-infected pregnant women, reproductive-aged women (15-45 years), and HIV uninfected pregnant women respectively, with no identified associated factors for HEV infection. One last article described an outbreak that affected 690 people with children’s predominance, only 49 samples were tested for HEV and 14 confirmed positive.Conclusions: Our study showed that HEV infection appears to be markedly underreported in Tanzania as evidenced by a significantly lower  reported prevalence compared to neighbouring countries with similar demographics. Increased awareness of this disease by health care  professionals and further epidemiological studies to establish the baseline data of the disease are needed urgently. Keywords: Hepatitis E, prevalence, epidemiology, review, Tanzani