Hepatitis E in Pregnant Women and the Potential Use of HEV Vaccine to Prevent Maternal Infection and Mortality

Purpose of Review Hepatitis E (HEV) is a continuing public health problem in developing countries, causing high mortality in pregnant women. This article reviews the latest knowledge on HEV in pregnancy, the vaccine candidates that have reached clinical trials, and their potential use during pregnancy. Recent Findings New evidence suggests that a genotype-specific tropism to uteroplacental cells contributes to the multifactorial pathology leading to the increased severity of HEV during pregnancy. Data from pregnant women inadvertently vaccinated are limited but show similar rates of adverse events as non-pregnant women, and no evident harm to newborns. Protective anti-HEV IgG antibodies are estimated to last longer after vaccination than natural infection. Accelerated vaccination appears safe and provides protective antibodies similar to a normal dosing regimen. Summary HEV239 is the most extensively studied vaccine and has been shown to be safe and effective, but more data are needed to recommend use of this vaccine on a global basis. Further studies should focus on safety and efficacy in pregnant women, and evaluate a shorter two-dose regime, which is highly warranted in outbreak situations.