Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 33 (28 August 2026)

Regional Situation: Across the Americas, influenza activity is generally declining or remains at interseasonal levels, although epidemic-level activity persists in Nicaragua, Panama, Ecuador, and Chile. Influenza B predominates in several countries, particularly in the Southern Cone, while A(H3N2) continues to predominate in parts of Central America and the Andean subregion. RSV activity remains elevated in several countries, particularly in Central America and the Southern Cone. Increasing activity is observed in Guatemala, Panama, Colombia, Argentina, and Chile, while particularly high positivity is reported in Paraguay and Uruguay. In contrast, RSV activity is low or declining across much of North America, the Caribbean, and parts of the Andean subregion. SARS-CoV-2 activity remains generally low or stable across North America, the Andean subregion, and the Southern Cone. However, increasing or elevated activity is observed in parts of the Caribbean and Central America, particularly in Belize, Barbados, the Cayman Islands, Mexico, and Nicaragua. Overall, ILI and SARI trends remain stable or declining in most subregions, although SARI activity remains elevated in Chile and Uruguay, largely associated with RSV circulation.