Influenza Update N° 513

Overview

^{Published 12 February 2025 | For reporting Week 5, ending 02 February 2025}

Influenza

• In the Northern hemisphere, influenza activity remained elevated in many regions, including part of North America (predominantly influenza A), Central America and the Caribbean (predominantly influenza A(H3N2)), Tropical South America (predominantly influenza B), Western Africa (predominantly influenza B), Northern Africa (predominantly A(H3N2)), Europe (due to seasonal influenza viruses of all subtypes) and Asia (predominantly influenza A(H1N1)pdm09). Activity increased in part of Northern America and parts of Eastern and Northern Africa, Europe and Asia.
• In the Southern hemisphere, elevated activity was observed in a few countries in Eastern Africa (predominantly influenza B) South-East Asia (predominantly A(H1N1)pdm09) and Melanesia (predominantly influenza A(H1N1)pdm09). In all other reporting countries, activity was similar or decreased in comparison to previous report.

 

SARS-CoV-2

• Elevated activity remained in some countries in South America, Eastern Africa and South Asia. All countries showed stable or declining trends.

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://www.who.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.