The effectiveness of two doses of recombinant hepatitis E vaccine in response to an outbreak in Bentiu, South Sudan: a case-control and bias indicator study.

Background: Hepatitis E virus (HEV) is a leading cause of acute viral hepatitis, particularly in Asia and Africa, where HEV genotypes 1 and 2 are prevalent. Although a recombinant vaccine, Hecolin, is available, it has not been used to control outbreaks. The licensed three-dose regimen might pose challenges for it to be an impactful outbreak control tool.

Safety of hepatitis E vaccine in pregnancy: an emulated target trial following a mass reactive vaccination campaign in Bentiu internally displaced persons camp, South Sudan.

Background: Epidemic forms of hepatitis E cause high mortality among pregnant people, with case fatality risks over 30% and adverse fetal outcomes. In 2022, the first mass reactive vaccination campaign against hepatitis E was conducted in South Sudan with the HEV239 vaccine. We aimed to assess whether vaccination against hepatitis E in pregnancy increases the risk of fetal loss in a cohort of vaccinated and unvaccinated pregnant people.

Vaccination coverage and adverse events following a reactive vaccination campaign against hepatitis E in Bentiu displaced persons camp, South Sudan.

Introduction: Hepatitis E (HEV) genotypes 1 and 2 are the common cause of jaundice and acute viral hepatitis that can cause large-scale outbreaks. HEV infection is associated with adverse fetal outcomes and case fatality risks up to 31% among pregnant women. An efficacious three-dose recombinant vaccine (Hecolin) has been licensed in China since 2011 but until 2022, had not been used for outbreak response despite a 2015 WHO recommendation.