Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 26 (4 July 2025)

Regional Situation: Regional Situation: Influenza activity continues to decline across the Americas. RSV circulation shows a slight decrease compared to the previous epidemiological week (EW), while SARS-CoV-2 activity remains low but has shown an upward trend in recent weeks. In North America, influenza activity has reached interseasonal levels. In the Caribbean, the previously reported increase in influenza circulation has leveled off and continues to decline. A(H1N1)pdm09 remains the predominant subtype. RSV activity remains low and stable in North America, while in the Caribbean, it remains low with a slight increase compared to the previous EW. SARS-CoV-2 activity has stabilized in North America at a 3.9% positivity rate, but continues to rise in the Caribbean, where positivity reached 14.4%. In Central America, influenza activity remains elevated but has continued to decline over the past four weeks, with a positivity rate of 21.5%. RSV activity remains stable and low, with a positivity rate of 1.9%, while SARS-CoV-2 circulation continues to increase, reaching a positivity rate of 8.9%. In the Andean subregion, influenza A has shown a steady decline in positivity over the past weeks, with a positivity rate of 10.7%. RSV activity also continues to decline, with a positivity rate of 7.7%, while SARS-CoV-2 circulation remains low and stable. In Brazil and the Southern Cone, influenza activity remains elevated but is showing a declining trend, mainly due to decreasing A(H1N1)pdm09 circulation, with a positivity rate of 8.0%. RSV circulation remains low with a positivity rate of 3.2%, while SARS-CoV-2 activity remains low at interseasonal levels. Across all subregions, an increase in the circulation of other respiratory viruses (ORV) has been observed, with an overall positivity rate of 9.5%, primarily driven by rhinovirus activity, particularly in North America, and the Caribbean.