Worldwide, hepatitis E is recognized as one of the leading causes of acute viral hepatitis. In France, hepatitis E can also lead to chronic forms of hepatitis in immunocompromised individuals or severe forms in people with chronic liver disease. To reduce the risk of transmission and protect the most vulnerable populations, Santé publique France is taking action. Santé publique France participates in monitoring the epidemiological trends of hepatitis E in collaboration with the National Reference Center for Enteric Hepatitis Viruses. Santé publique France also provides information to healthcare professionals to support them in their daily practice.

Epidemiological surveillance of hepatitis E

Surveillance by the National Reference Center (CNR) for Enterically Transmitted Hepatitis Viruses

As part of its infectious disease surveillance missions, Santé publique France relies on annual data and the expertise of the National Reference Center (CNR) for Enteric-Transmitted Viruses (hepatitis A and E) for the surveillance of hepatitis E.

From 2002 to 2010, this surveillance was conducted by the Val de Grâce Military Teaching Hospital (Paris); in 2011 by the Paul Brousse University Hospital; and, since 2012, by the Toulouse University Hospital.

The CNR’s surveillance relies on voluntary submissions of samples (blood, stool) or regular data from public and private laboratories within its network. More information at: http://www.cnrvha-vhe.org.

The CNR is also responsible for characterizing strains (genotypes 1, 2, 3, 4) and monitors trends in the circulation of different viral subtypes in France. This surveillance allows for a comparison of strain circulation in human and animal populations. Finally, this documentation by the CNR can also assist in the investigation of clustered cases by determining the genotype, subgroup, and sometimes sequence homologies, which help establish whether or not the cases are linked.

The data reported by the CNR enable the description of the epidemiological and virological characteristics of hepatitis E cases diagnosed in France.

Regular supplementary analyses

At the same time, Santé publique France regularly analyzes reimbursement data for diagnostic tests and data from the Medical Information Systems Program (PMSI).

Anti-HEV seroprevalence studies

Anti-HEV seroprevalence studies were conducted between 2003 and 2012 among blood donors in various regions (Pays-de-Loire, Île-de-France, Midi-Pyrénées) and at the national level.

A national study of the general population was conducted in 2009–2010 (Séro-Inf), as well as in specific populations such as homeless individuals in Marseille (2003–2006) and expatriates working for a Marseille-based company providing services abroad (2011–2012).

Finally, two seroprevalence studies (2002–2003, 2011–2012) were conducted in populations exposed to HEV as part of their occupation in various metropolitan regions (forestry workers, pig farmers).

Investigation of Hepatitis E Cluster Cases

Between 2007 and 2013, 9 investigations of clusters of hepatitis E cases among people who had shared a meal were documented, providing information on potential sources of infection, among other things.

Descriptive study of indigenous cases of acute hepatitis E

In 2010, a national descriptive study of indigenous cases of acute hepatitis E was conducted in metropolitan France by the InVS and the CNR. Its objectives were to describe the clinical and epidemiological characteristics of indigenous cases of acute hepatitis E diagnosed in 2010, to detect and investigate clusters of cases, and to characterize the viruses involved in human infections.