Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 19 (16 May 2025)

Regional Situation: In general, North America and parts of the Caribbean continue to see a decline in influenza activity, mainly associated with influenza A(H1N1)pdm09 and influenza B. RSV activity remains at interseasonal levels in North America, while in the Caribbean, it continues to decline. SARS-CoV-2 activity remains low in North America, but in the Caribbean, it shows a slight increase. In Central America, influenza A(H1N1)pdm09 circulation continues its downward trend in recent epidemiological weeks (EW), with a positivity rate of 18.4%. RSV activity is shifting toward an increase, while SARS-CoV-2 circulation remains low. The Andean subregion shows a decrease in SARS-CoV-2 circulation and an increase in influenza A(H3N2) detection. RSV circulation continues to rise, with a positivity rate of 11.9%. In Brazil/Southern Cone, influenza A(H1N1)pdm09 continues its upward trend, with a positivity rate of 22.2%. SARS-CoV-2 detection remains low, while RSV is trending upward, with a positivity rate of 4.3%. Across the region, there is a high percentage (9.6%) of detections of other respiratory viruses (ORV), with rhinovirus standing out in North America, as well as in the Andean region, Brazil, and the Southern Cone. Parainfluenza circulation has been detected in the Caribbean.