2023-01-08-世界卫生组织-Influenza_Update_N°_436_12页_1022kb

Key Recommendations

• Monitor co-circulation of influenza and SARS-CoV-2.
• Enhance integrated surveillance and step up influenza vaccination campaigns in northern hemisphere countries to prevent severe disease and hospitalizations.
• Clinicians should consider influenza in differential diagnosis for high-risk groups and follow national guidelines for testing and treatment.
• Comparisons with previous seasons should be cautious due to pandemic impacts and potential under-reporting.
• Report data through FluNet or regional platforms.

Global Influenza Activity

• Influenza activity remained elevated primarily due to activity in the northern hemisphere.
• Influenza A viruses predominated, with A(H3N2) representing a larger proportion in many regions.

Regional Highlights

• North America: High influenza activity; decreasing indicators but stable in some areas. A(H3N2) predominant; hospitalizations elevated in children and older adults.
• Europe: Activity increasing; positivity above epidemic threshold in many areas. A(H3N2) predominant; increases in hospitalizations and severe outcomes like pediatric deaths.
• Central Asia: Relatively high activity due to A(H1N1)pdm09 and B virus detections.
• Northern Africa: Influenza detections rise with all subtypes present.
• Western Asia: Activity decreasing, but some increases noted.
• East Asia: Low overall activity, but increases in specific countries like Mongolia and Republic of Korea.
• Caribbean/Central America: Decreasing influenza activity; Mexico shows elevated positivity.
• Tropical South America: Generally low activity; A(H3N2) predominant; moderate increases in some countries.
• Tropical Africa: Low activity in most areas, but increases in eastern Africa.
• Southern Hemisphere Temperate Zones: Activity low in South Africa and high but declining in Argentina, Chile, and others; A(H3N2) predominant in some.

SARS-CoV-2 Surveillance

• SARS-CoV-2 positivity varies by region: highest in Americas (over 30%) and Western Pacific (>25%), lower in other WHO regions.
• WHO encourages integrated surveillance of influenza and SARS-CoV-2.
• Sentinel surveillance reports show co-circulation in many countries.

Notes on Data

• Data completeness limited by reporting delays and year-end holidays; comparisons with prior seasons should be cautious.
• Data sources include FluNet, regional platforms, and WHO surveillance systems.

This summary captures the main points and trends from the Influenza Update N° 436.