GLOBAL INFLUENZA SURVEILLANCE AND RESPONSE SYSTEM (GISRS) Co-circulationInfluenza SUMMARY (Based on data reported to WHO for week 46, ending 16 November 2025) Globally, influenza activity was elevated with positivity over 10% in week 46. SARS-CoV-2 activity remained low while influenza predominated in all areaswith positivity above 10% in the Northern and Southern hemisphere temperate and subtropical areas but below 10% in Tropical areas. [Figures 1a, 1b, 1cand 1d] . qInfluenza Globally, influenza activity continued to increase with influenza A viruses predominantly detected in all zones. [Figure 2] In the northern hemisphere, influenza activity remained low in most countries although increasing activity was reported in some countries. Influenzapercent positivity was elevated in a few countries in Central America and the Caribbean, Northern and Middle Africa, South West and EasternEurope and was over 30% in a few countries in Western and Eastern Africa, Northern Europe, Western, Southern and South-East and Eastern Asia. In the southern hemisphere, influenza activity remained low and stable in most countries with elevated positivity (>10%) in a single country inTropical South America and two countries in Temperate South America. Percent positivity was over 30% in single countries in Eastern Africa and In the zones with elevated positivity, influenza A(H1N1)pdm09 predominated in Central America and the Caribbean, Northern, Eastern and MiddleAfrica whereas influenza A(H3N2) was predominant in all other zones. [Figures 5 and 6] qSARS-CoV-2 Globally, SARS-CoV-2 positivity remained stable at low levels, with some countries reporting elevated positivity (>10%) in Central America and theCaribbean, Northern and Eastern Europe and Temperate South America. Percent positivity was over 30% in one country in South West Europe. qRespiratory Syncytial Virus (RSV) RSV percent positivity remained elevated in a few countries in Central America and the Caribbean, with one country reporting positivity >30%, andsingle countries in Tropical South America, Western Africa and South West Europe. Compared to the previous reporting period, RSV positivityremained stable across most countries, with increases in activity in two countries in Central America and the Caribbean and one country in South Co-circulation of influenza and SARS-CoV-2 1b) Weekly numbers of influenza andSARS-CoV-2 virus specimens tested and Influenza SARS-CoV-2 Respiratory syncytial virus Additional information Data and methods The data presented in this report originates from virologic surveillance conducted by countries, areas, and territories (CATs) andsubmitted to WHO FluNet through participation or collaboration with the Global Influenza Surveillance and Response System This report includes virologic data from bothsentinel surveillance and other systematically conducted surveillance. Dueto differences in surveillance strategies, direct comparisons of percent positivity between CATs should be interpreted with caution. To assess trends, the proportion of specimens tested positive for influenza or SARS-CoV-2 was smoothed over a 3-weeks period. Thisanalysis includes only countries that tested 10 or more specimens in at least two of the three weeks. Weekly changes in the smoothedpositivity rate for each virus were calculated as absolute differences from the previous week. These absolute changes were cate- The influenza transmission zones map is based on data aggregated over a 3-weeks period, moving backward from the current weekuntil a minimum threshold of 100 tested samples is reached within each influenza transmission zone. Pie charts are displayed onthe map only if the total percent positivity in a influenza transmission zones map is 20% or higher. All trend analyses are based Activity summaries are organized by geographical groupings of CATs.These groupings are intended solely for geographicreference and do not imply uniformity in respiratory virus transmission patterns within each group. It is important to note that Suggested citation:Global respiratory virus activity:weekly update No 554 (week 2025-46).Geneva:World HealthOrganization; 2025; Licence: CC BY-NC-SA 3.0 IGO. Disclaimer: The designations employed and the presentation of the material in this publication do not imply the expression of any opinionwhatsoever on the part of WHO concerning the legal status of any country, territory, city or area or of its authorities, or concerning The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommendedby WHO in preference to others of a similar nature that are not mentioned.Errors and omissions excepted, the names of All reasonable precautions have been taken by WHO to verify the information contained in this publication.However, thepublished material is being distributed without warranty of any kind, either expressed or implied. The responsibility for the Additional survei