Key Points

• Since January 1, 2025, 838 cases of measles have occurred and been reported (including 6 cases in September). The decline in the number of cases observed since May continued in September.

• Of these cases, 293 (35%) were hospitalized (including 12 in intensive care), 115 cases (14%) developed complications (including 68 cases of pneumonia and 2 cases of encephalitis); 2 deaths were reported.

• The median age of cases is 17 years. The three age groups most affected are adults aged 40 and older (14%), children aged 1–4 years (14%), and adolescents aged 15–19 years (12%).

• Among the individuals targeted for vaccination (aged over one year and born since 1980), for whom vaccination status was known (n=580), 377 (65%) were unvaccinated or incompletely vaccinated, 187 (32%) had received two doses, and 16 (3%) had been vaccinated without the number of doses received being specified.

• 70 departments in France (69%) reported at least one case during the period, including 4 cases reported in the Overseas Territories (Réunion). The five departments with the highest number of reported cases are: Nord (15%), Bouches-du-Rhône (6%), Aude (6%), Haute-Savoie (5%), and Isère (5%).

• During the period, 110 clusters of cases (groups of epidemiologically linked cases) were reported to the Regional Health Agencies (ARS) (provisional, unconsolidated data) for a total of 507 cases. Among these, 30 clusters involved 5 or more cases, and none are currently active.