Luxembourg Health Authorities Issue Final Respiratory Review of Season

On Friday 28 March 2025, the Health Directorate of Luxembourg's Ministry of Health and Social Security published its weekly retrospective concerning the evolution of the main acute respiratory infections including COVID-19, influenza and respiratory syncytial virus (RSV).

The health authorities also announced that, as a result of the gradual decline in the circulation of respiratory viruses, the review would be the last of the current winter season. The next retrospective report is expected to be published in October 2025.

During week 12, from Monday 17 to Sunday 23 March 2025, the number of influenza (flu) cases reported by laboratories decreased from 387 to 253, down 35% compared to the previous week. The downward trend in the number of cases has been confirmed for the past seven weeks.

During the week in question, there were 43% influenza A and 57% influenza B among the typed results. According to the latest available data, the subtypes identified among  the influenza A virus samples were A(H1)pdm9 (42%) and A(H3) (58%).

Regarding RSV, the number of reported cases decreased by 20%, with 57 confirmed cases, compared to 71 the previous week.

The health authorities noted that the number of positive COVID-19 / SARS-CoV-2 cases has fluctuated over the past five weeks. It increased from 25 to 28 cases in week 12, a 12% increase compared to the previous week, but remains at a relatively low level. The viral concentration detected in wastewater also fluctuated over the past five weeks and showed an increase during the week concerned.

The latest available sequencing data revealed that three JN.1 subvariants, the XEC variant (57.7%), the KP.3 variant (12.9%) and the LP.8.1 variant (12.9%), predominated in February.

HOM