Data
The hepatitis A surveillance system established by Santé publique France makes it possible to study the epidemiological trends of the infection.
In France, an average of 1,100 cases has been reported each year since 2006, when mandatory reporting was introduced, with a minimum of 411 cases reported in 2020 and a maximum of 3,391 cases reported in 2017. There was a decrease in the incidence rate between 2020 and 2022, due to the indirect effects of the COVID-19 pandemic.
Number of cases and annual reporting rate per 100,000 inhabitants, mandatory reporting of acute hepatitis A, all of France, 2006–2025
The male-to-female ratio is generally close to 1.2 when the virus is circulating normally, outside of any epidemic affecting a specific population. The age group most affected is children aged 5 to 14.
A peak in cases occurs in September and October
A peak in cases is observed every year between September and October. This is primarily due to cases imported from areas with higher endemicity, where individuals become infected while on summer vacation during July and August.
Thus, approximately 40% of the cases reported each year had traveled outside metropolitan France in the 2 to 6 weeks prior to the onset of symptoms.
About 40% of cases reported each year report another case among their close contacts.
An Outbreak in Europe in 2017
It is worth noting that in 2017, a Europe-wide outbreak of acute hepatitis A occurred, primarily affecting men who have sex with men (MSM). That year, 3,391 cases were reported in France, with a peak in reporting in July (500 cases). As a result, the sex ratio increased from 1.09 in 2016 to 3.63 in 2017.
The age group most affected was those aged 26 to 45, and the proportion of imported cases decreased from 46% in 2016 to 26.8% in 2017. Vaccination efforts were hampered by shortages of the hepatitis A vaccine. Nevertheless, public education, the organization of vaccination sessions, and preventive measures implemented in response to individual cases contributed to the gradual containment of the outbreak.
In relation to
Vaccination
thematic dossier
Contagious diseases most often affect children at a very young age. Because children are particularly vulnerable, they are a priority target for vaccination programs.
Outbreaks of foodborne illness
thematic dossier
A foodborne illness outbreak is defined as the occurrence of at least two cases with similar symptoms—typically gastrointestinal—that can be traced to a single food source. In France, such...
