Respiratory infections in Luxembourg are not abating

The Luxembourg Health Directorate has published its weekly review of the main acute respiratory infections. The picture remains mixed: seasonal flu and respiratory syncytial virus are gradually receding, while COVID-19 cases are on the rise again.

During the fourth calendar week of 2026, laboratories recorded 740 cases of influenza, compared to 872 a week earlier, representing a 15% decrease. This is the second consecutive decline in figures, but the circulation of the virus is still considered high. Almost all typed cases (99.9%) were influenza A, with influenza B remaining minimal. The Ministry of Health and Social Protection reminds us that vaccination is still relevant, especially for people over 65 who are at increased risk of complications. Vaccination is still considered the most reliable way to prevent and reduce serious consequences.

A similar trend can be observed for RSV. The number of confirmed cases decreased by 14% — from 145 to 125 in a week. Since October 2025, 58% of all infections have been in children under the age of ten, confirming that the virus primarily affects younger age groups.

Against this backdrop, the COVID-19 situation looks different. Over the same period, the number of positive SARS-CoV-2 tests rose from 65 to 88 cases, an increase of 35% compared to the previous week. At the same time, the concentration of the virus in wastewater, which is used as an additional indicator of the spread of infection, decreased slightly. The latest sequencing data show that the XFG variant (45.5%), its subvariant XFG.3 (26.7%) and the NB.1.8.1 variant (18.2%) are predominant in the country.