Key Points

COVID-19

In the Pays de la Loire region, SARS-CoV-2 transmission remains high, impacting the healthcare system and healthcare utilization. In Week 50, the regional incidence rate has generally stabilized, though it remains at a high level (364 per 100,000 inhabitants). The incidence rate continued to rise among those aged 15–30 and was higher among those under 45. Those under 15 still had a high testing rate in Week 50. The positivity rate was stable or decreasing across all age groups. As in mainland France, the L452R mutation (primarily carried by the Delta variant) remained the overwhelming majority among screened results at the regional level.

Enhanced surveillance of the Omicron variant (B.1.1.529), which was classified as a VOC by the WHO and the ECDC on November 26, 2021: as of December 23 at 4:00 PM, 1,440 confirmed cases of Omicron variant infection had been detected in France, including 8 in the Pays de la Loire region. National data from Flash surveys confirm a rapid increase in Omicron detection, which accounted for 0.3% of interpretable sequences in Flash survey S48 and 2.1% in Flash survey S49 (unconsolidated data) (see PEN). Information updates on Omicron are regularly posted on the Santé Publique France website.

Bronchiolitis

The Pays de la Loire region has been in an epidemic phase for bronchiolitis since S41, marking the 10th consecutive week (see map opposite). After a peak in activity observed in S48, healthcare utilization for bronchiolitis among children under 2 years of age decreased in S49 and generally stabilized in S50, remaining at a high level and above alert thresholds. RSV circulation reported by the virology laboratories at the Nantes and Angers university hospitals generally stabilized in weeks 49 and 50 at a high level.

Influenza and influenza-like illness

The Pays de la Loire region is not currently in a pre-epidemic phase (see map opposite). Emergency department visits for influenza-like illness were slightly higher in week 50, but remained relatively low and at levels typically observed at this time of year. SOS Médecins calls for influenza-like illnesses remained stable in week 50. An increase in influenza A isolates among children was reported by the virology laboratory at Nantes University Hospital in week 49, which stabilized in week 50.

Acute gastroenteritis

A marked increase in emergency department visits for acute gastroenteritis, particularly affecting children under 5 years of age.