Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 15 (24 April 2026)

Regional situation: Influenza activity in the Americas continues to decline with an overall positivity of 7.8%. This aggregate trend contains critical heterogeneity reflecting Northern Hemisphere countries post-winter resolution where cases are still predominantly associated with influenza B; while some Southern Hemisphere countries are entering early pre-season or active epidemic onset, being influenza A the predominant subtype across the Caribbean, Central America, Andean, and Southern Cone subregions. RSV activity remains stable over the past weeks, with low regional positivity (1.9%). SARS-CoV-2 continues at low interseasonal levels (2.4%) with no resurgence signal across the region. ORV circulation is sustained and slightly increasing (3.6%), driven predominantly by rhinoviruses. SARI and ILI indicators also reflect the interseasonal declining trend in the Northern Hemisphere with influenza as the primary etiological agent; while the Southern Hemisphere carries the primary burden for this reporting period.