2024-02-25-世界卫生组织-Influenza_at_the_human-animal_interface_summary_and_assessment,_26_February_2024_8页_258kb

报告摘要

Summary: Influenza at the Human-Animal Interface (22 Dec 2023 – 26 Feb 2024)

Overview

During the period 22 December 2023 to 26 February 2024, reports documented an increase in human cases of infection with influenza viruses at the human-animal interface. These include avian influenza viruses (A(H5N1), A(H5N6), A(H9N2), A(H10N5)) and swine-origin influenza viruses (A(H1N1) variant). The overall risk assessment indicates a low public health risk, with no sustained human-to-human transmission identified for any of these viruses. Enhanced surveillance and continued vigilance are advised.

New Infections

The following cases were officially reported:

Influenza A(H5N1): Five human cases from Cambodia.
Influenza A(H5N6): One human case from China.
Influenza A(H9N2): One case from Hong Kong, SAR, China.
Influenza A(H10N5): One human case from China.
Influenza A(H1N1) Variant: Two cases, one from Brazil and one from Spain.

Risk Assessment

Overall Risk

The overall public health risk remains unchanged and is assessed as low. Human infections with animal-origin influenza viruses are uncommon but can occur through contact with infected animals or contaminated environments. Sustained human-to-human transmission is currently considered unlikely for all reported viruses. International spread via travellers is also considered unlikely if no sustained transmission exists.

Specific Virus Assessments

A(H5N1)

Risk of Sporadic Cases: Low impact, expected but unusual if exposure occurs.
Human-to-Human Transmission: Unlikely; no sustained transmission documented.
International Spread: Possible via travellers, but community-level spread unlikely.

A(H5N6)

Risk of Sporadic Cases: Cases can occur with exposure to poultry; mild clinical illness typical.
Human-to-Human Transmission: Unlikely.
International Spread: Minimal risk.

A(H9N2)

Risk of Sporadic Cases: Expected with animal exposure; low public health impact.
Human-to-Human Transmission: Unlikely sustained transmission.
International Spread: Unlikely further community spread.

A(H10N5)

Risk of Sporadic Cases: First human case detected; expected in exposed individuals.
Human-to-Human Transmission: Unlikely.
International Spread: Based on limited evidence, unlikely further spread.

Swine Influenza (A(H1N1) Variant)

Risk of Sporadic Cases: Expected due to virus circulation in swine; mild illness typical.
Human-to-Human Transmission: Unlikely; cases usually involve animal contact.
International Spread: Possible via travellers, but no sustained community transmission.

Risk Management Recommendations

Surveillance and Reporting: Continue global surveillance for influenza viruses. All new influenza subtypes must be reported under the International Health Regulations (IHR, 2005). Viruses should be characterized and shared with WHO's Global Influenza Surveillance and Response System (GISRS).
Public Advice: Avoid contact with sick or dead animals, practice good hygiene, and cook poultry thoroughly. Travellers in affected areas should avoid farms and live animal markets.
Vigilance: Enhanced surveillance in potentially exposed human populations is necessary. Collaboration between animal and human health sectors is essential for early detection.
Travel and Trade: No special traveller restrictions are advised. Refer to WHO and WOAH guidelines for safe animal trade practices.