Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 40 (16 October 2026)

Regional situation: In EW 40, influenza activity shows an increasing trend in the Caribbean, Central America and the An-dean Subregion, with recent increases in the Cayman Islands, the Dominican Republic, Honduras, El Salvador, Panama and Bolivia. In North America it remains at low levels, and in Brazil and the Southern Cone it has stabilised at around 10% following the peak in EW 22. Influenza A predominates in North America, the Caribbean and Central America, with A(H1N1) in the north and the Caribbean and A(H3N2) in Central America. Influenza B predominates in the Andean Subregion and in Brazil and the Southern Cone, and its proportion has increased in recent weeks in North America and Central America. RSV is decreasing in Central America, the Andean Subregion and Brazil and the Southern Cone, although it remains the main virus identified in SARI cases in the latter two subregions and in Central America. SARS-CoV-2 circulation is low or decreasing in most subregions, with moderate levels in some Caribbean countries. Positivity for other respiratory viruses is high in Brazil and the Southern Cone, above previous seasons, with rhinovirus predominating in all subregions except the Andean Subregion, where adenovirus predominates. SARI cases show a decreasing trend in Brazil and the Southern Cone and in the Andean Subregion, except in Panama, where they remain above previous seasons.