Key Points

• Since January 1, 2026, 44 cases of measles have been reported, including 14 new cases in March. The number of cases reported during the first quarter of the year is therefore significantly lower than that observed in 2025 (341 cases).

• Of these 44 cases, 18 (41%) were hospitalized (including 2 in intensive care), and 11 cases (25%) developed complications (including 5 cases of pneumonia and 1 case of encephalitis). No deaths have been reported.

• The median age of cases is 20.9 years. The three age groups most affected are infants under one year of age (20%), adults aged 20–24 (18%), and adults aged 40 and older (18%).

• Among the individuals targeted for vaccination (aged over one year and born since 1980) for whom vaccination status was known (n=25), 16 (64%) did not have an up-to-date vaccination status, while 9 (36%) had received two doses.

• 22 departments (22%) reported at least one case during the period. The five departments with the highest number of reported cases are: Paris (14% of cases), Hauts-de-Seine (14%), Essonne (11%), Bouches-du-Rhône (7%), and Savoie (7%). No cases were reported in the overseas territories.

• During the period in question, 8 outbreaks (clusters of epidemiologically linked cases) were reported to the Regional Health Agencies (ARS) for a total of 22 cases (provisional, unconsolidated data). Among these outbreaks, only one involving 5 or more cases occurred in a daycare center and is still active.