Last update
Week 47 review - 20 to 26 November 2023
The weekly retrospective gives a summary of trends in acute respiratory infections, including COVID-19 and influenza (influenza virus) and respiratory syncytial virus (RSV).
Trends of the week:
COVID-19: slight increase in the number of cases of COVID-19.
Respiratory syncytial virus (RSV): sharp rise in the number of RSV cases.
Influenza: increase in the number of influenza cases.
COVID-19/SARS-CoV-2
From 20 to 26 November 2023 (week 47), the number of people testing positive for SARS-CoV-2 increased to 319 cases, compared to 259 cases the previous week (+23%).
The positivity rate remains more or less unchanged at 22%. Virus levels detected in wastewater increase slightly. [1]
The latest sequencing data available show a preponderance of the EG.5.1 variant (31%) and the proportion of the BA.2.86 variant has increased to 6%. [2]
Influenza
For the week of 20 to 26 November 2023 (week 47), the number of influenza cases reported by laboratories increased to 43 cases compared to 24 cases in the previous week, an increase of 79% compared to the previous week.
This data largely overlaps with LNS sentinel surveillance, which indicates increased circulation of rhinoviruses, SARS-CoV-2 and RSV in particular, but little circulation of influenza viruses [2].
Respiratory syncytial virus (RSV)
For the week of 20 to 26 November 2023 (week 47), the number of respiratory syncytial virus (RSV)-positive individuals detected by the CHL laboratory rose to 100 cases, compared with 55 the previous week, presenting an increase of 82%.