2021-06-21-世界卫生组织-Influenza_at_the_human-animal_interface_summary_and_assessment,_22_June_2021_7页_228kb

Influenza at the Human-Animal Interface: May-June 2021 Summary

New Infections

During the period from May 22 to June 22, 2021, WHO reported official cases of human infections with influenza viruses, including one A(H5N6), two A(H9N2), one A(H10N3), two A(H1N2)v, and one A(H3N2)v. An additional A(H1N1)v case was detected.

Overall Risk Assessment

• The public health risk from known influenza viruses at the human-animal interface remains stable.
• Sustained human-to-human transmission is low for all reported viruses.
• Human infections are primarily associated with animal contact, and further cases are expected due to ongoing animal circulation.

Risk Assessments by Virus Type

Avian Influenza Viruses

• A(H5): One A(H5N6) case in China; additional cases possible due to animal circulation. No sustained transmission; traveler spread unlikely without community spread.
• A(H7N9): No recent detections; risk unchanged.
• A(H9N2): Two cases in China; human-to-human transmission low; primary exposure linked to poultry.
• A(H10N3): One case in China; assessed as incidental; limited evidence of transmission risk.

Swine Influenza Viruses

• A(H1)v: Cases in the USA and Taiwan; no evidence of sustained human-to-human transmission.
• A(H3)v: One case in Canada; low transmission risk; epidemiologic investigations ongoing.

Overall Risk Management Recommendations

1. No travel restrictions or enhanced screening advised at entry points.
2. Travelers should avoid animal contact and practice good hygiene in affected areas.
3. Continuous global surveillance is critical for detecting virologic and epidemiologic changes.
4. IHR (2005) requires immediate reporting of laboratory-confirmed human infections with new influenza subtypes.
5. Collaboration between animal and human health sectors is essential for vigilance and response.

Links

• WHO Human-Animal Interface web page
• WHO Protocol for investigating non-seasonal influenza