2014-12-03-世界卫生组织-Influenza_at_the_human-animal_interface_summary_and_assessment,_4_December_2014_4页_328kb

Summary of Influenza at the Human-Animal Interface (as of 4 December 2014)

Avian Influenza A(H5N1)

• Total laboratory-confirmed human cases from 2003 to 4 December 2014: 676, with 398 deaths.
• Since 2 October 2014, Egypt reported 8 new cases (including 5 fatal), mostly from November 2014, associated with exposure to sick or dead backyard poultry.
• Human-to-human transmission is rare; community spread risk is low based on no major changes in virus characteristics.

Influenza A(H1N2) Reassortant Virus

• Identified in Sweden during studies involving pig and human contact.
• Caused infections in asymptomatic swine farmers, with no human-to-human transmission detected.
• Genetic analysis shows minimal human health impact due to existing immunity and ongoing monitoring.

Influenza A(H3N2)v Virus

• One additional case detected in the US, bringing total for 2014 to three human infections.
• Cases involve close contact with swine; community spread risk is considered low.

Influenza A(H7N9) Viruses

• WHO is closely monitoring this; separate risk assessments are available online.

Other Non-Seasonal Influenza Viruses and Animal Outbreaks

• Global avian influenza outbreaks are at expected levels; enhanced surveillance for H5N1, H7N9, and other subtypes.
• All non-seasonal influenza cases are reportable under IHR (2005); continuous monitoring advised to detect changes in virus behavior.

Overall Public Health Risk Assessment

• The risk of community-level spread for these viruses remains low, as human infections are rare and transmission is not easy among people or animals.
• Ongoing surveillance is critical, especially over winter months, to detect any emerging threats and characterize influenza viruses in both human and animal populations.

Links

WHO human-animal interface web page

• http://www.who.int/influenza/human_animal_interface/en/
  Avian influenza A(H7N9) information
• http://who.int/influenza/human_animal_interface/influenza_h7n9/en/index.html