Indigenous hepatitis E virus infection in England: More common than it seems

Background: Indigenous hepatitis E virus (HEV) is increasingly diagnosed in England due to abetter awareness and understanding of the virus. However, the true burden of infection and therefore its implication to public health remains undefined. Objectives: To estimate the HEV seroprevalence in the general population and to investigate how the risk of HEV infection had fluctuated over time. Study design: Two sample collections stratified by age ranging from 1 to 80 years, were screened for HEV IgG antibody. The two collections were separated by 13 years enabling the average incidence between 1991 and 2004 to be estimated. Additional force of infection calculations were also undertaken. Results: An overall HEV antibody prevalence of 13% was determined, increasing with age and peaking at 25% in those aged over 50 years. Analysis of the two sample collections demonstrated a temporal shift in seroprevalence indicating that the risk of acquiring HEV infection was not solely age dependant. Data showed that the force of infection had been particularly high in the middle of the 20th century but had subsequently decreased. Current HEV incidence estimates revealed that the incidence did not vary in different age groups. Conclusions: This study indicated a high anti-HEV seroprevalence in England and that there was a period of increased risk of acquiring HEV infection which has now decreased. Incidence estimates show that shared risk factors still exist for acquiring HEV infection across all age groups in England. (C) 2009 Elsevier B.V. All rights reserved.