Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 41 (23 October 2026)

Regional situation: In EW 41, influenza activity remains high in the Caribbean and shows recent increases in El Salvador, Bolivia, Ecuador and Barbados. In Central America and the Andean Subregion it remains stable at around 10%. In North America it remains at low levels, and in Brazil and the Southern Cone it has decreased below 10%. Influenza B predominates in the Andean Subregion, in Brazil and the Southern Cone and in Mexico, and its proportion is increasing in Central America, where A(H3N2) pre-dominates. In the Caribbean, influenza A, mainly A(H1N1), and influenza B are co-circulating. RSV remains high in Central America, with increases in Honduras and Nicaragua, and is increasing in the Caribbean and in Mexico. In the Andean Subregion and in Brazil and the Southern Cone it continues to decrease, although it remains the main virus identified in SARI cases in Central America and in Brazil and the Southern Cone. SARS-CoV-2 circulation is low in all subregions, with a decrease in the Caribbean and a slight increase in Brazil, where it predominates among ILI detections. Positivity for other respiratory viruses is high in Brazil and the Southern Cone, above previous seasons, with rhinovirus predominating; in the Andean Subregion, the proportion of adenovirus is notable. SARI cases show a decreasing trend in Brazil and the Southern Cone and in the Andean Subregion. In Panama they remain above previous seasons.