Based on data reported to WHO for week 47, ending 23 November 2025

Influenza

Globally, influenza activity continued to increase with influenza A viruses predominantly detected in all zones.

In the northern hemisphere, influenza percent positivity was elevated in countries in Central America and the Caribbean, Africa, Northern and South-West Europe and in Asia, with positivity over 30% in some countries in Western and Eastern Africa, Northern Europe, Western, Southern, Eastern and South-East Asia. Increases in activity were observed in countries in Central America and the Caribbean, Northern and Eastern Africa, Northern and South West Europe, Western, Southern, South-East and Eastern Asia.

In the southern hemisphere, influenza activity remained low overall although elevated positivity (>10%) was reported in a few countries in Tropical and Temperate South America, Eastern and Southern Africa and Oceania; percent positivity was over 30% in a single country in South-East Asia. Small increases in activity were observed in Tropical South America, Southern Africa, South-East Asia and Oceania.

In the zones with elevated positivity, influenza A(H1N1)pdm09 predominated in Northern and Middle Africa whereas influenza A(H3N2) was predominant in all other zones except Central America and the Caribbean where there was codominance of the two subtypes.

SARS-CoV-2

Globally, SARS-CoV-2 positivity remained stable at low levels, with some countries reporting elevated positivity (>10%) in Central America and the Caribbean, Temperate South America, Southern Africa, Europe, and South-East Asia. Percent positivity was over 30% in a single country in South West Europe. Small increase in activity was reported in single countries in Central America and the Caribbean, Temperate South America, Northern and South West Europe and South-East Asia.

Respiratory Syncytial Virus (RSV)

RSV activity was low overall although elevated percent positivity was reported in few countries in Central America and the Caribbean, Tropical South America, South West Europe and Southern Asia. Compared to the previous reporting period, RSV positivity remained stable across most countries, with increases in activity in single countries in Central America and the Caribbean and South West Europe. RSV and influenza activity were both elevated in two countries in Central America and the Caribbean, and one country in South West Europe and Southern Asia, respectively.

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.