Influenza Update N° 552

Overview

Published 12 November 2025 | For reporting Week 44, ending 02 November 2025

Globally, influenza and SARS-CoV-2 activity remained low in week 44. Influenza predominated all areas with positivity around 10% in the northern hemisphere temperate and subtropical areas, and over 10% in the tropical areas and southern hemisphere temperate and subtropical areas.

Influenza

Globally, influenza activity remained low, with influenza A viruses continuing to predominate.

In the northern hemisphere, influenza activity remained low in most countries. Influenza percent positivity was elevated in a few countries in Central America and the Caribbean, Northern Africa, Northern Europe, Southern and Eastern Asia, and was over 30% in Western, Eastern and Middle Africa, Western and South-East Asia. Small increases in activity were observed in countries in Central America and the Caribbean, Western and Middle Africa, Europe and Asia.

In the southern hemisphere, influenza activity remained low and stable in most countries with elevated positivity (>10%) in a single country in Temperate South America and two countries in Eastern Africa and percent positivity over 30% in a single country in South-East Asia. Small increases in activity were observed in single countries in Temperate South America, Middle and Eastern Africa.

In the zones with elevated positivity, influenza A(H1N1)pdm09 predominated in Central America and the Caribbean, Northern and Middle Africa whereas influenza A(H3N2) was predominant in Temperate South America, Western Africa, Northern Europe, Western, Southern and South-East Asia. Influenza A(H1N1)pdm09 and influenza A(H3N2) were codominant in Eastern Africa.

SARS-CoV-2

Globally, SARS-CoV-2 positivity increased but remained at low levels, with some countries reporting elevated positivity (>10%) in Tropical and Temperate South America, South West and Eastern Europe, and Eastern Asia. Percent positivity was over 30% in one country in South West Europe and Western Asia. Increase in activity was reported in single countries in South-West Europe and Western Asia.

Respiratory Syncytial Virus (RSV)

RSV percent positivity remained elevated in Central America and the Caribbean with two countries reporting positivity over 30%, and single countries in Western and Eastern Africa and Eastern Asia. Compared to the previous reporting period, RSV positivity remained stable across most countries, with increases in activity in a few countries in Central America and the Caribbean and one country in South West Europe. RSV and influenza activity were both elevated in one country Central America and the Caribbean and one country in Western Africa.

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.

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.