Weekly updates, Influenza Epidemiological Week 3 (27 January 2023)

North America: Influenza activity declined in the subregion. Influenza A(H3N2) predominated with the co-circulation of A(H1N1)pdm09 and B/Victoria (where subtyping and lineage were determined). The SARS-CoV-2 activity was elevated, while RSV activity was low. In Canada, influenza activity has decreased; surveillance indicators continued within expected levels. In Mexico, influenza activity was at the average of previous seasons, with low severity indicators. In the United States, influenza activity declined at low-intensity levels, with the percentage of deaths due to pneumonia, influenza, and COVID-19 above the average of previous seasons. RSV activity continued decreasing.

Caribbean: Influenza activity continued moderate in the subregion with influenza B viruses predominance. Influenza B/Victoria
virus predominated, with A(H1N1)pdm09 and A(H3N2) cocirculation. Influenza activity was elevated in Belize, with B/Victoria predominance. The SARS-CoV-2 activity was low, with increased activity in some countries. RSV activity was at baseline levels,
except in the Dominican Republic. 5

Central America: Influenza activity was moderate, with influenza A and B virus detections and B/Victoria predominance. Influenza activity was elevated in Guatemala and Honduras, with influenza B/Victoria predominance. Overall, SARS-CoV-2 percent positivity decreased in the subregion; increased percent positivity was reported in Honduras and Panama. RSV activity remained raised in Guatemala.

Andean: Influenza activity was low, with the predominance of influenza B/Victoria and co-circulation of influenza A(H3N2) and A(H1N1)pdm09. Bolivia and Ecuador reported increased influenza activity. SARS-CoV-2 was elevated in Colombia, Ecuador, and Peru. In the subregion, RSV activity was low overall.

Brazil and Southern Cone: Influenza activity was low, with the predominance of influenza B (lineage undetermined) viruses and influenza A (subtyping not performed) co-circulation. The SARS-CoV-2 activity was elevated across the subregion but with a decreasing trend in most countries. Brazil and Chile reported increased RSV activity.

Avian Influenza: A summary of the avian influenza situation in the region, case management and recommendations are available at Epidemiological alerts and updates | PAHO/WHO | Panamerican Health Organization (paho.org)