In week 04/2026the activity for acute respiratory infection (IRA) remained very contrasting depending on the type of healthcare use and the data source. In city medicineactivity continued to increase among children under 15 and stabilized among those 15 and over according to data from the Sentinels/IQVIA network, remaining at a moderate level of intensity. On the other hand, the share of activity for low IRA SOS Médecins decreased in all age groups, and was at a low intensity level. To EMERGENCIESactivity for low AKI decreased and was at a low intensity level in all age groups. This activity was still mainly driven by the circulation of influenza viruses.
Figure : Regional alert level for influenza and bronchiolitis
- Seasonal flu
The circulation of influenza viruses remained very active in mainland France.
Overall, the use of care for flu/flu-like illness decreased in all age groups in town and in hospital.
One wouldin S04, the rate of consultations for all ages combined for influenza-like illness estimated from Sentinels and IQVIA network data increased; it was 269 per 100,000 inhabitants vs. 261 per 100,000 in S03. The use of care for influenza-like illness remained mixed depending on the type of care use. Sentinels and IQVIA network data show a slight increase in consultation activity for all ages. For SOS doctor, the share of consultations for flu syndrome decreased for all ages combined. Overall, the level of intensity is moderate among children and low among those aged 15 and over.
At the hospitalin S04, influenza syndromes explained 2.6% of visits to the emergency room (- 0.5 pt compared to S03) and the share of hospitalizations after visits to the emergency room (2.6%) decreased by 0.5 point. Overall, the proportion of hospitalizations after a visit to the emergency room for flu/flu-like syndrome was 20.2%, this rate being more than 60% among those over 65 years old.
From S40, 973 serious cases (+156 compared to S03) hospitalized in intensive care were reported by the services participating in the surveillance: 56% were 65 years or older, 88% presented at least one comorbidity and 72,2% cases whose vaccination history was known, were not vaccinated.
The share of influenza among deaths declared by electronic certificate was decreasing for the second consecutive week (5.3% vs 6.5% in H03).
And S03, all regions were still in epidemic, including Corsica.
In S04, the positivity rate for influenza among samples decreased among samples taken in city laboratories (39.7%; -2.3 points compared to S03) and in hospitals (14.9%, -1.4 pt) while remaining at moderate levelsand increased in old-fashioned medicine (52.1%; +9 pt).
Type A viruses largely predominated.
- In the city, of the 846 viruses typed since S40, 35.8% are type A(H1N1)pdm09, 52.1% are type A(H3N2) and 9.2% are non-subtyped A viruses; four B viruses have been identified.
- In the hospital, out of 23,600 viruses typed 99.6% are type A. Of the 3640 type A viruses subtyped, 41.5% are type A(H1N1)pdm09, and 58.5% are type A(H3N2).
Between weeks 48 and 52/2025, a total of 232 A(H1N1), 199 A(H3N2) viruses and 3 B(VIC) viruses were sequenced by the CNR Respiratory Infection Virus. The majority subclade was subclade K (191/199; 96%) for the A(H3N2) subtype, and subclade D.3.1.1 (213/232; 92%) for the A(H1N1) pdm09 subtype. The three B viruses sequenced belong to the Victoria lineage (subclade C.5.5, C.5.6.1 and C.5.7).
In Overseasthe territories of the Antilles and Guyana remained in an epidemic, while Mayotte had returned to post-epidemic and Reunion Island to a basic level.
Au December 31, 2025THE vaccination coverage influenza were estimated at 46.3% among all targeted people, 53.3% among those aged 65 and over et 27.1% among those under 65 at risk severe flu. These estimates are higher than those observed at the same date in 2024.
The first estimates of the real-world effectiveness of the flu vaccine against influenza virus infection have been published (see January 16 news).
The syndromic indicators of bronchiolitis increased in town and in hospital for all ages, to levels close to those observed the previous season at the same period.
The intensity level of bronchiolitis remained at its baseline level in the city and in the hospital.
In S04, compared to S03, the positivity rate for RSV for all ages decreased slightly in medical biology laboratories (6.7%; -0.2 pt) and significantly in community medicine (7.4%; -4.8 pt) and increased slightly in hospitals (5.8%; -0.5 pt).
In France, the Burgundy-Franche-Conté region was in post-epidemic mode. The Ile de France, Normandy, Brittany and Pays de Loire regions were at a basic level, with the other regions being post-epidemic.
In the overseas departments and regions, Guadeloupe and Martinique remained in an epidemic, Mayotte was in an epidemic. Indicators in Guyana were at a basic level, just like in Reunion this week.
3. Covid 19
COVID-19 syndromic indicators remained stable and at low levels in the city and in the hospital. The positivity rate for SARS-CoV-2 was stable in the city and in the hospital, but increasing in community medicine. The tracking indicator for SARS-CoV-2 in wastewater was decreasing. The share of electronically certified COVID-19 deaths was slightly decreasing.
4. Medical-social establishments
A total of 131 (vs. 259 in S02) new episodes of clustered ARI cases occurred in week 03 (unconsolidated data). Of the 96 episodes for which the cause is known, 76% were attributed exclusively to the flu.
Source: Public Health France. Bulletin Acute respiratory infections. Week 04 (January 19 to 25, 2026). Published: January 28, 2026.
