2022-05-29-世界卫生组织-Influenza_Update_N°_420_13页_1mb

Influenza Update Summary: May 30, 2022

This update discusses the global influenza surveillance based on data up to May 15, 2022, noting that COVID-19 pandemic measures have influenced influenza transmission, surveillance, and testing.

• Global Context: Influenza activity decreased globally after peaking in March 2022, with COVID-19 impacts affecting health-seeking behaviors and testing capacities.

• Recommendations: Countries are advised to prepare for co-circulation of influenza and SARS-CoV-2 by enhancing integrated surveillance monitoring both viruses simultaneously, accelerating influenza vaccination to prevent severe disease, and considering influenza in differential diagnoses, especially in high-risk groups.

• Regional Summary:

  • Northern Hemisphere Temperate Zones: In North America, influenza activity was stable with higher-than-usual positivity; A(H3N2) predominant. In Europe, activity declined with A(H3N2) leading. Central Asia reported no detections. Northern Africa had a single A(H3N2) case. Western Asia saw low activity except in Georgia and Qatar.
  • Southern Hemisphere Temperate Zones: Influenza activity was generally low, except in Argentina and Chile. In Oceania, detection rates increased in some areas; South Africa and Australia showed low to moderate activity.
  • Tropical Zones: Most regions reported low activity. In the Caribbean and Central America, A(H3N2) was predominant. Tropical South America had moderate activity in some countries. Tropical Africa and Asia reported low detections, with variations like in India and Sri Lanka.

• SARS-CoV-2 Integration: COVID-19 sentinel surveillance showed increasing positivity (e.g., up to 13% globally), with region-specific variations. Integration of influenza and SARS-CoV-2 surveillance is encouraged.

• Data Details: Over 224,003 specimens tested positive for influenza, mostly A(H3N2) and B-Victoria lineage. Data from 111 countries were reported, and SARS-CoV-2 positivity varied by WHO regions.

• Suggested Actions: Enhanced surveillance, vaccination campaigns, and clinical consideration for influenza in light of COVID-19's ongoing influence.