Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 16 (25 April 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 is approaching interseasonal levels in North America; however, an increase is observed in the Caribbean. SARS-CoV-2 activity remains low but shows an upward trend in North America and the Caribbean. In Central America, the circulation of influenza A(H1N1)pdm09 is on the rise, with a positivity rate of 24.2%. RSV and SARS-CoV-2 activity remain low. The Andean subregion remains stable in SARS-CoV-2 circulation, with a decreasing trend in influenza A(H3N2) and RSV. In Brazil and the Southern Cone, influenza A(H1N1)pdm09 continues its upward trend, presenting a positivity rate of 8.8%. SARS-CoV-2 continues to decline. RSV detection has increased compared to the previous epidemiological week (EW). The region has a high detection rate (9.5%) of other respiratory viruses (ORVs), with rhinovirus being predominant in North America, the Andean region, and Brazil/Southern Cone. In the Caribbean, parainfluenza circulation has been detected.