Regional Update, Influenza and Other Respiratory Viruses. Epidemiological Week 47 (28 November 2025)

Regional Situation: Influenza activity in the Americas remains at low levels with an upward trend, with a positivity of 4.6%. RSV circulation remains at low levels in the last epidemiological week (EW), while SARS-CoV-2 shows a downward trend with a positivity of 6.7%. In North America, influenza and RSV activity remain at low levels with an upward trend. SARS-CoV-2 decreases compared to the previous EW, with a positivity of 6.5%. In the Caribbean, circulation of influenza A(H1N1)pdm09 is increasing, with a positivity of 12.7%. RSV activity continues to rise, reaching a positivity of 21.3%, and SARS-CoV-2 also increases slightly compared to the previous EW, presenting a positivity of 6.2%. In Central America, influenza activity is increasing, with a positivity of 8%. SARS-CoV-2 remains at low and stable levels, while RSV increases this week with a positivity of 18.6%. In the Andean subregion, influenza A activity increases slightly this week to 6.8%, and RSV decreases to 3.6% positivity. SARS-CoV-2 increases compared to the previous EW, presenting a positivity of 6%. In Brazil and the Southern Cone, influenza activity continues to rise (12.1% positivity), with circulation mainly of influenza A(H3N2) and influenza B. RSV circulation reaches interseasonal levels, while SARS-CoV-2 remains at low levels with a stable trend (7% positivity). Circulation of other respiratory viruses (ORV) decreases to 3.2% at the regional level. The main viruses detected regionally correspond to rhinovirus and parainfluenza.