Weekly update, Influenza Epidemiological Week EW 39 (12 October 2022)

North America: Influenza activity remained low throughout the subregion. Influenza A(H3N2) predominated with the co-circulation of influenza A(H1N1)pdm09 and influenza B (lineage undetermined). SARS‐CoV‐2 activity continued to decrease. In Canada, influenza was at interseasonal levels, while SARS‐CoV‐2 cases increased among those aged 60 and older. In Mexico, influenza activity increased at low-intensity levels with declined SARS-CoV-2 activity. In the United States, influenza activity was at interseasonal levels, while SARS-CoV-2 activity continued to decrease, with elevated RSV activity.

Caribbean: Influenza activity remained at baseline levels, with the predominance of the influenza A(H3N2) virus. In Saint Lucia, SARS-CoV-2 activity continues increased, while Jamaica reported increased pneumonia activity.

Central America: Influenza activity remained low, predominating influenza A(H3N2) with the co-circulation of influenza B/Victoria. In Guatemala, influenza activity increased, predominating influenza A(H3N2). In Costa Rica, SARS-CoV-2 activity continues elevated, while in Panama and Guatemala RSV activity continues increased. Overall, in the subregion RSV circulation continues to increase.

Andean Countries: Influenza activity remained low, with influenza A(H3N2) predominance. Venezuela reported an increased influenza activity with circulation of influenza A(H3N2).

Brazil and Southern Cone: Influenza activity remained low in the subregion, although an increasing trend was observed in recent weeks, likely due to increased activity at moderate intensity levels in Argentina, and Brazil, where the activity remained low. Influenza A(H3N2) was predominant, followed by influenza A(H1N1)pdm09 and influenza B (lineage undetermined) detections. The SARS-CoV-2 activity was low throughout the subregion. Increased RSV activity was reported in Brazil and Uruguay, where SARI activity continued above the average epidemic levels.