Weekly update, Influenza Epidemiological Week EW 37 (september, 28)

North America: Influenza activity remained low in the subregion, with circulation of influenza A(H1N1)pdm09, influenza B (lineage undetermined), and the predominance of influenza A(H3N2). SARS‑CoV‑2 activity continued to be elevated but decreasing. In Canada, influenza was at interseasonal levels, while SARS‑CoV‑2 cases increased among those aged 20-59 and 80 and older. In Mexico, influenza activity remained increased at low-intensity levels and declined SARS-CoV-2 activity. In the United States, influenza activity was at interseasonal levels, while SARS-CoV-2 activity was moderate, although decreasing.

Caribbean: Influenza activity remained low with the predominance of the influenza A(H3N2) virus. Dominica, the Dominican Republic, and Saint Lucia reported increased SARS-CoV-2 activity, while ILI consultations were increased in Martinique.

Central America: Influenza activity remained at low levels, predominating influenza A(H3N2). In El Salvador and Guatemala, influenza activity increased, predominating influenza A(H3N2). In Costa Rica, SARS-CoV-2 activity continues elevated. Increased RSV activity continues to be reported in Nicaragua and Panama.

Andean Countries: Influenza activity remained low, with influenza A(H3N2) predominance. In addition, Bolivia and Ecuador reported SARS-CoV-2 at low activity levels.

Brazil and Southern Cone: Influenza activity remained low, with the detection of influenza A(H1N1)pdm09, influenza B (lineage undetermined), and the predominance of influenza A(H3N2). The SARS‑CoV-2 activity was low throughout the subregion. However, increased RSV activity was reported in Brazil and Uruguay in recent weeks.