OBJECTIVES: This study was performed to determine the seroprevalence and incidence of hepatitis E virus (HEV) infection among HIV-infected women during pregnancy and after delivery in a cohort of 200 Tanzanian women.

METHODS: HIV-infected women participating in a study on antiretroviral therapy for the prevention of mother-to-child HIV transmission between 2006 and 2011, were tested retrospectively for anti-HEV immunoglobulin G (IgG) in plasma samples at 9 months post-partum. Anti-HEV IgG-positive patients were tested for anti-HEV IgG and immunoglobulin M (IgM) in samples from enrolment, and seroconverting women were tested for HEV RNA.

RESULTS: A total of 16 women were anti-HEV IgG-positive, two of whom had seroconverted between enrolment and 9 months post-partum, with no detection of anti-HEV IgM or HEV RNA, yielding an HEV seroprevalence of 8.0% (confidence interval 5.0-12.6%) and an annual incidence rate of 1.0% (confidence interval 0.2-3.4%). CD4 cell counts were relatively high (median 403×106/l), with no significant difference between women with and without serological signs of HEV.

CONCLUSIONS: An annual HEV infection incidence rate of 1% strongly indicates ongoing transmission of HEV in Tanzania and should be kept in mind for pregnant women presenting with signs of acute hepatitis.