The campaign to prevent French babies from contracting the main virus that causes bronchiolitis will begin on September 1 in mainland France and a large part of overseas territories and will last until the beginning of next year, the Ministry of Health announced on Thursday.
Starting about two weeks earlier than the previous autumn-winter, the campaign will focus on the same two treatments: for newborns and children under one year old, Beyfortus (nirsevimab), an injectable synthetic antibody developed by AstraZeneca and marketed by Sanofi, and for pregnant women, Pfizer's Abrysvo vaccine, which is administered at the end of pregnancy.
It can only be one or the other, except for a mother who received Abrysvo but gave birth much earlier than expected without having had time to transmit the antibodies to her baby.
Bronchiolitis is primarily caused by the seasonal respiratory syncytial virus (RSV). Although generally mild, the disease can lead to serious complications requiring hospitalization.
It remains the leading cause of hospitalization for infants under one year old. However, the advent of preventive treatments has helped change this situation in recent years.
For the 2024-2025 season in mainland France, the bronchiolitis epidemic, from mid-November to mid-January, was "of shorter duration (8 weeks) and of lower intensity than previous epidemics, before the implementation of childhood immunization and maternal vaccination, particularly in infants under 3 months old," the ministry notes.
By the end of February 2025, approximately 352,000 doses of Beyfortus had been covered by health insurance and more than 91,000 Abrysvo vaccines, a sign of "strong uptake," according to its press release.
For the new season, children born from September 1st until the end of the campaign will be able to receive a dose of Beyfortus in the maternity ward a few days after birth. The treatment will then be fully covered and without any upfront costs.
For children born between February and August 2025, catch-up treatment will be possible in general practice. In this case, the treatment is only reimbursed at 30% by Health Insurance but can be fully reimbursed with C2S (complementary health solidarity) or AME. The remaining cost varies, otherwise, depending on the mutual insurance company, if the parents have one.
The Beyfortus, available since the beginning of August in French Guiana, will be available from September in mainland France, Réunion, Martinique, Guadeloupe, Saint Martin and Saint Barthélemy, and from October in Mayotte.
For pregnant women wishing to be vaccinated (in the 8th month), the Abrysvo vaccine is covered at 100%.
Parents and those around babies are also encouraged to take simple preventive measures to limit the transmission of the virus.
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