Key Points

Acute respiratory infections

• The winter season was marked by sustained activity of acute respiratory infections, occurring in two distinct waves:
  • in October, primarily linked to COVID-19,
  • in December dominated by respiratory syncytial virus (RSV) and influenza.
• The pattern of succession among respiratory viruses was similar to the trends observed during the two previous seasons.
• Overall moderate use of healthcare services, both in private practice and in emergency departments, with levels lower than those recorded during the previous season, but high levels of activity during peaks, similar to those of the past season.
• Nearly 4 out of 10 emergency department visits for acute respiratory failure resulted in hospitalization.

Influenza

• Pattern similar to previous seasons, lasting 11 weeks between early December and mid-February, with a peak in activity in early January in emergency departments and mid-January in primary care.
• Overall moderate intensity, particularly in primary care.
• Emergency department visits and hospitalizations were down compared to 2024–2025 but higher than in 2023–2024.
• High rate of hospitalizations following emergency department visits, comparable to the previous season, particularly among people aged 65 and older and children under 5 years of age.
• Almost exclusive prevalence of type A viruses, mainly the AH3N2 subtype.

Bronchiolitis

• A shorter and less intense epidemic, lasting 7 weeks (vs. an average of 11 weeks), confirming the downward trend observed as early as 2024–2025.
• Peak activity recorded in early December, with 11.3% of SOS Médecins calls involving infants under 1 year of age (S49-2025) and 22.3% of emergency room visits (S50-2025).
• Activity levels were well below those of previous seasons, coinciding with the launch of the monoclonal antibody immunization campaign (Beyfortus®) to prevent RSV infections in infants.

COVID

• Increased activity in private practice and emergency departments in late August–early September 2025 (S35-2025).
• Peak in early October 2025 (S40-2025), followed by a gradual decline through early November (S45-2025).
• Subsequently stabilizing at very low levels.
• Dynamics similar to 2024–2025, but with overall lower activity levels.

Mortality

• Excess mortality from all causes averaging +19.8% over the first four weeks of January 2026, with peaks reaching +23.1% and +22.2% in W01 and W03-2026.
• A 28.1% increase in the number of all-cause deaths certified electronically between weeks 52-2025 and 01-2026, coinciding with peaks in activity for influenza and influenza-like illness in emergency departments.
• Among the causes of death recorded via electronic death certification, 4.4% were directly attributed to influenza throughout the epidemic phase, with a peak of 8.8% during the second week of January.