Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 28 (18 July 2025)

Regional Situation: Influenza activity across the Americas continues to decline, while RSV circulation remains on an upward trajectory. SARS-CoV-2 activity is low and stable compared to previous epidemiological weeks (EWs). In North America, influenza activity remains at interseasonal levels. In the Caribbean, the previously reported increase in influenza circulation persists, with a positivity rate of 13,9%. A(H1N1)pdm09 continues to be the predominant subtype. RSV activity remains low and stable in North America, while in the Caribbean, it reached a positivity rate of 7,9% following recent increases in the latest weeks. SARS-CoV-2 activity has stabilized in North America and declined in the Caribbean, where positivity reached 9,1%. In Central America, influenza activity remains elevated but shows a downward trend, with a positivity rate of 15%. RSV activity increased compared to the previous week but remains at low levels, while SARS-CoV-2 circulation is decreasing. In the Andean subregion, influenza A activity increased compared to the previous week, reaching 12,7% positivity. RSV activity also increased, reaching a positivity rate of 11%, while SARS-CoV-2 circulation remains low and stable. In Brazil and the Southern Cone, influenza activity remains elevated, but the observed declining trend persists, with a positivity rate of 8,6%. RSV circulation remains increasing but low with a positivity rate of 7,5%, while SARS-CoV-2 activity continues at low levels. Across all subregions, the circulation of other respiratory viruses (ORV) remains elevated, with an overall positivity rate of 8,5%, primarily driven by rhinovirus activity.