First Case of Mpox Variant Clade 1b Detected in France: What We Know

A first human case of the mpox variant clade 1b, also known as monkeypox, has been identified in France, according to a statement released on Monday, January 6, by the Ministry of Health. This unprecedented case on French territory involves a woman hospitalized in Rennes, Brittany. The patient has not traveled to Central Africa, a region where this variant has been actively circulating for several months. However, she had contact with two individuals who recently returned from this area. Investigations are ongoing to trace the source of the infection and identify at-risk contacts.

A More Contagious Variant Detected in Other Countries

This clade 1b variant, considered more contagious and associated with a higher fatality rate, has also been detected in Sweden, Germany, the United Kingdom, and Belgium since the summer of 2024. Unlike previous strains, which caused localized lesions, this variant is characterized by widespread skin rashes across the entire body.

A Global Outbreak of Concern Since 2022

Mpox is a viral disease transmitted from animals to humans but can also spread through close physical contact with an infected person. In 2022, a global outbreak caused by clade 2 had already affected countries where the disease was not endemic.

Vaccination and Preventive Measures

In France, health authorities report 215 cases of mpox in 2024 and emphasize the importance of vaccination, particularly for targeted populations: men who have sex with men, sex workers, and transgender individuals with multiple partners. Vaccination recommendations now include a booster dose for those already vaccinated.

Despite this new case, authorities consider the risk of infection by the clade 1b variant to remain low for the general population in France and Europe, according to the European Centre for Disease Prevention and Control (ECDC). The detection of this variant does not, at this stage, change the current response strategy.