National Surveillance of Enterovirus D68 Upsurge, France, 2024

In 2024, an early and rapid rise in enterovirus D68 (EV-D68) infections in France prompted the implementation of enhanced nationwide surveillance to characterize the outbreak. EV-D68 screening was performed as part of the routine hospital strategy of the 2 national reference laboratories and of the national surveillance of enterovirus infections. Of 919 patients, 49.1% (451/919) were adults. Severe infection was reported in 169 patients (102 children and 67 adults). We observed neurologic complications in 7 children (seizures and encephalitis) and 4 adults (myelitis). Infections peaked in week 38 and were associated with subgenotypes A2 and B3; A2 predominated, particularly in adults (317/457 [69.3%] A2 infections). Complete genome analyses identified a new A2-derived lineage with mutations clustering in exposed regions of viral capsid protein 1. Our findings highlight the substantial clinical impact of EV-D68 in adults as well as children, underscoring the need for broad clinical and genomic surveillance.