Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 36 (18 September 2026)

Regional Situation: Respiratory virus activity remained heterogeneous across the Americas. Influenza activity was generally low or at interseasonal levels in North America, Central America, and much of the Andean subregion, while higher activity persisted in parts of South America, with influenza B becoming increasingly prominent during the latter part of the season in several Southern Cone countries. RSV activity remained low in North America and the Caribbean and generally declined or stabilized in Central America and the Andean subregion, although elevated activity persisted in Panama and several Southern Cone countries. SARS-CoV-2 activity remained low and stable across much of South America but continued at higher levels in parts of the Caribbean and Central America, with increasing activity observed in some settings.