Influenza Update N° 517

Overview

^{Published 12 March 2025 | For reporting Week 9, ending 02 March 2025}

Influenza

• In the Northern hemisphere, influenza activity in general remained the same or decreased except in a few countries in Central America and the Caribbean, Europe and Western Asia. Activity remained elevated in North America (predominantly A(H1N1)pdm09), Central America and the Caribbean and Tropical South America (predominantly A(H1N1)pdm09 and A(H3N2)), Western and Northern Africa (predominantly A(H1N1)pdm09), Europe (all seasonal subtypes), Asia (Central: predominantly B viruses, Eastern: predominantly A(H1N1)pdm09, Western: predominantly A(H3N2), Southern: all seasonal subtypes and South-East Asia: co-circulation of A(H1N1)pdm09 and B viruses).
• In the Southern Hemisphere, activity was low except in single countries in Eastern Africa and South-East Asia and Oceania, where elevated activity was observed.

 

SARS-CoV-2

• Globally, SARS-CoV-2 activity continued to be low across reporting countries with a few exceptions of elevated activity reported in Temperate South America.

WHO encourages countries, especially those that have received the multiplex influenza and SARS-CoV-2 reagent kits from GISRS, to conduct integrated surveillance of influenza and SARS-CoV-2 and report epidemiological and laboratory information in a timely manner to established regional and global platforms. The guidance can be found here https://covid.comesa.int/publications/i/item/WHO-2019-nCoV-integrated_sentinel_surveillance-2022.1.
 

Starting with report #501, the Global Respiratory Virus Activity Weekly Update included data from sentinel surveillance and other types of systematically conducted virologic surveillance. Countries, areas, and territories use a variety of approaches to monitor respiratory virus activity and data in this report may vary from surveillance reports posted elsewhere. Analyses stratified by source of surveillance is available through Respimart.