Hepatitis A is an acute liver infectious disease caused by the hepatitis A (VHA) virus. It is transmitted mainly in a fec-oral or food and never becomes chronic, unlike hepatitis B or C. Viral hepatitis most widespread worldwide, it generates variable risks according to the health conditions of the countries. In France, a country of low endemicity, progress in hygiene has made rare infection, but collective immunity has decreased, increasing the receptivity of adults.
Instructions of cases in the Nantes metropolis
A DGS-Urgent alert of July 28 reported a significant resurgence of cases of hepatitis A in the Nantes agglomeration. Since the beginning of June 2025, more than 25 acute infections by the VHA have been observed there. This increase, although the incidence grows overall in Europe after a post-Cavid-19 decrease, indicates a viral circulation currently very active, capable of increasing locally.
Hepatitis A is a compulsory declaration disease in France. The report is necessary for the tracing of cases and the implementation of prophylactic measures for contacts. Laboratories are also asked to send samples to the national reference center for hepatitis for serotyping, in order to identify the transmission chains, especially during grouped cases or unusual epidemiology.
Hepatitis A vaccination: Target recommendations and audiences
Vaccination is systematically recommended for the family entourage or life communities in precarious hygiene situations, ideally within 14 days of the appearance of clinical signs of the index case.
It is also recommended as a preventive basis for certain risk groups, constituting an effective means of prevention, well tolerated and providing protection from 10 to 20 years. Administble from 1 year, it consists of an intramuscular injection followed by a reminder between six months and a year later.
It is particularly recommended for:
- Young people welcomed in establishments for disabled childhood and youth, as well as patients with cystic fibrosis or chronic hepatobiliary pathologies (the vaccine is reimbursed in these specific cases);
- Children, from 1 year old, born of families, a member of which is from a country of high endemicity and likely to stay there;
- Men with sex with men (HSH);
- Some professional personnel exposed, such as those dealing with non -clean children (e.g. crèches) or those in charge of treatment of wastewater and sewers.
It is important to note that vaccination does not exempt from maintaining hygiene measures, fundamental to protect yourself from other infections.
Essential hygiene measures against hepatitis A
Personal hygiene rules are essential: frequent hand washing after the toilet, after changing a baby, and before manipulating or consuming food. Infected persons should scrupulously respect these rules to avoid contamination of those around them.
For travelers, it is advisable to consume cooked or peeled fruits and vegetables and bottled water, avoiding raw or insufficiently cooked shells.