Key Point

Mumps Outbreaks in France Over the past few months, several mumps outbreaks have been reported in France at universities and among young adults. Outbreaks have also been reported in other countries under similar circumstances (e.g., in the U.S., Israel, Ireland, etc.). Mumps is an infectious disease caused by a paramyxovirus, which, in the pre-vaccination era, circulated endemically in communities of children and young adults. Human-to-human transmission occurs through respiratory secretions and saliva. The incubation period is between 12 and 25 days (usually 16 to 18 days). Clinical signs include unilateral or bilateral parotitis, generally accompanied by fever. Asymptomatic cases account for 30% of all cases. Possible complications include meningeal complications (meningitis, encephalitis, hearing loss) and other glandular disorders, such as orchitis after puberty. These complications are more common in adults. The patient is contagious 7 days before parotitis and up to 9 days afterward (duration of school exclusion). Among the most recent cases reported in France, a significant proportion had been vaccinated with one or two doses of the MMR vaccine. This finding has led the InVS to question the relative efficacy of the vaccine, and a study is currently underway.In this context, we remind you that any mumps outbreak must be reported to the ARS so that control measures can be implemented (exclusion, information, vaccination, enhanced hygiene measures) and for possible inclusion in the InVS vaccine efficacy study.