Key Points

COVID-19

After stabilizing at a high level, viral circulation is on the rise again and has surpassed 1,000 cases per 100,000 inhabitants. In Week 12, the COVID-19 incidence rate continued to rise for the third consecutive week, following six weeks of decline (Weeks 4–9). The positivity rate is also rising, approaching the January 2022 peak of 41%. At the same time, the health impact remains low, with new hospitalizations and critical care admissions continuing to decline in Week 11, as does the weekly death toll. The Omicron variant still accounts for 100% of interpretable sequences. The BA.2 sublineage is spreading rapidly, rising from 13% of Omicron sequences in W05 to 74% in W10. An uptick in respiratory syncytial virus circulation is being observed among children under 2 years of age.

Bronchiolitis

Transition to the pre-epidemic phase. Surveillance indicators for bronchiolitis in children under 2 years of age continue to rise, with 106 emergency department visits in S12 compared to 87 in S11, representing a 22% increase. Visits for bronchiolitis account for 25% of all visits across all conditions. The bronchiolitis epidemic is intensifying in Réunion.

Influenza

Following an increase in emergency department visits for influenza-like illness (n=14), surveillance indicators returned to their baseline levels in S-09 and S-10. Hospital virological surveillance did not identify any influenza-positive biological samples in February 2022.