Key points

Acute Respiratory Infections (ARI)

• A season characterized by high demand for medical care due to ARIs and marked by two peaks: one in late December, linked to the bronchiolitis outbreak among young children, and another in late January, due to the flu outbreak, which was severe across all age groups.

Bronchiolitis

• In Occitanie, the outbreak was brief (6 weeks), lasting from late November 2024 to early January 2025. The peak of the outbreak occurred in week 51, just before the Christmas holidays.

• The bronchiolitis outbreak was of low intensity. Syndromic and virological indicators were lower than in the two previous seasons.

• Since the introduction of monoclonal antibodies in the fall of 2023, in addition to a marked decrease in the number of healthcare visits for bronchiolitis, there has been a decrease in hospitalizations among the youngest patients seen in the hospital (under 3 months of age).

• Starting in 2025–2026, surveillance will focus on children under 1 year of age, in accordance with the HAS guidelines for the management of the first episode of bronchiolitis.

Influenza

• In Occitanie, the epidemic lasted 12 weeks, from December 2024 to the end of February 2025. The epidemic peak was reached in week 04 or 05, depending on the data source.

• In both community practice and hospitals, the influenza epidemic was of high intensity. Syndromic and virological indicators were higher than in the two previous seasons.

• A significant impact was observed on hospitalizations, as well as in long-term care facilities and on mortality.

• An exceptional co-circulation of the three viruses A(H1N1)pdm09, A(H3N2), and B/Victoria was observed.

• Regional vaccination coverage was slightly lower than last season among at-risk individuals targeted for vaccination, nursing home residents, and nursing home staff. While vaccination coverage was high among nursing home residents, it was insufficient in the at-risk population.

COVID-19

• The circulation of COVID-19 was more active between June and October 2024, peaking in September 2024.

• Unlike in previous years, there was no resurgence of viral circulation during the winter of 2024–2025.

• Levels for most indicators were lower than those of the previous season.

• People aged 65 and older continued to account for the majority of emergency room visits and hospitalizations following such visits due to Covid-19.

• Regional vaccination coverage was low and declining, particularly among residents and staff at long-term care facilities.

All-cause mortality

• All-cause death rates were significantly higher than expected from week 2025-01 through week 2025-08 (except in week 2025-06 among those aged 65 and older).