Weekly update, Influenza. Epidemiological week 34 (September 8, 2022)

North America: Overall, influenza activity remained low in the subregion, and influenza A(H3N2) predominated. SARS-CoV-2 activity continued to be elevated but decreasing. In Mexico, influenza activity increased, and SARS-CoV-2 positivity continued elevated but decreasing. In the United States, influenza activity was at interseasonal levels, while SARS-CoV-2 activity remained high, although decreasing.

Caribbean: Overall, influenza activity remained low, with influenza A(H3N2) predominated. In Belize, influenza activity was at moderate-intensity levels, with influenza A(H3N2) circulating. Saint Lucia reported increased SARS-CoV-2 activity. In Haiti, increased SARS-CoV-2 and SARI activity was reported. RSV activity increased in the Dominican Republic.

Central America: Overall, influenza activity remained stable at low levels, predominating influenza A(H3N2). In Panama, influenza activity increased to low-intensity levels,   with   influenza   A(H3N2)   predominance. Honduras, Nicaragua, and Panama reported increased RSV activity.SARS-CoV-2 activity increased in Honduras and Panama.

Andean Countries: Overall, influenza activity remained low, with influenza A(H3N2) predominance. SARS-CoV-2 activity continues elevated in Ecuador and Peru, with increased SARI activity.

Brazil and Southern Cone: Overall, influenza activity remained low, with the predominance of influenza A(H3N2). The SARS-CoV-2 activity was low throughout the subregion, except in Argentina. In Chile, influenza activity continue elevated.

Global: Influenza activity remained low. Overall, activity has decreased or remained low in most countries during this period, except in some countries in tropical countries in Africa and Asia. In the temperate zones of the southern hemisphere, overall influenza activity appeared to decrease during this reporting period. In Oceania, detections of primarily influenza A(H3N2) decreased overall, and influenza-like activity (ILI) was at or returned to low levels in most Pacific Island countries. In Southern Africa, influenza activity remained stable with continued detections of influenza A(H1N1)pdm09, influenza A(H3N2), and a few influenza B viruses. In tropical Africa, influenza activity decreased with influenza A(H3N2) viruses predominant among the reported detections. In Southern Asia, influenza detections of predominantly A(H3N2) viruses decreased while detections of influenza A(H1N1)pdm09 increased in recent weeks, especially in India. In South-East Asia, influenza activity decreased overall, with influenza A(H3N2) viruses predominating. In Europe, overall influenza activity remained at inter-seasonal levels, with influenza A(H3N2) predominant among the subtyped viruses. In Central Asia and Northern Africa, no influenza detections were reported. In East Asia, influenza activity of predominantly influenza A(H3N2) decreased overall, although a slight increase was reported in the northern provinces of China. Elsewhere, influenza illness indicators and activity remained low. In Western Asia, low numbers of detections of influenza A(H1N1)pdm09, A(H3N2), and B viruses were reported.

COVID-19 positivity from sentinel surveillance decreased to approximately 25% in the reporting period. The highest positivity rate was reported in the Americas region, while it remained below 20% in the other regions. The positivity rate decreased in most regions except South-East Asia and Western Pacific Regions, with a slight increase in the most recent week. Positivity from non-sentinel sites decreased to approximately 25% also.