Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 21 (30 May 2025)

Regional Situation: In general, North America and parts of the Caribbean continue to see a decline in influenza A(H1N1)pdm09 and influenza B activity. RSV activity remains at interseasonal levels in North America, while in the Caribbean, it has remained stable compared to previous epidemiological weeks (EW). SARS-CoV-2 activity remains low in North America, but in the Caribbean, it shows an increase. In Central America, influenza A(H1N1)pdm09 circulation has increased compared to previous EWs, with a positivity rate of 18.9%. RSV activity has risen compared to the previous week, while SARS-CoV-2 circulation remains low. The Andean subregion maintains a stable trend in SARS-CoV-2 circulation, while influenza A(H3N2) detection has increased, showing a positivity rate of 19.5%. RSV circulation remained steady compared to the previous EW, with a positivity rate of 10.1%. In Brazil/Southern Cone, influenza A(H1N1)pdm09 circulation remains at high levels, with a stable trend compared to the previous EW, showing a positivity rate of 18.1%. SARS-CoV-2 detection remains low, while RSV maintains a stable trend, with a positivity rate of 2.8%. Across the region, the positivity rate of other respiratory viruses (ORV) has declined to 7.8%, with rhinovirus standing out in North America and the Andean region.