Avian influenza overview December 2025-February 2026

Area of Science:

• Veterinary Virology
• Zoonotic Disease Epidemiology
• Public Health Surveillance

Background:

• High pathogenic avian influenza (HPAI) A(H5) virus detections have been reported in numerous European countries between November 2025 and February 2026.
• Wild bird populations, particularly waterfowl, show a high prevalence of HPAI A(H5), with significant spillover into domestic poultry and other animals.

Purpose of the Study:

• To report the epidemiological situation of HPAI A(H5) in Europe during the specified period.
• To assess the risk of avian influenza virus transmission to mammals, including humans.

Main Methods:

• Surveillance data collection on HPAI A(H5) detections in domestic and wild birds across 32 European countries.
• Analysis of HPAI A(H5) virus circulation patterns, species affected, and geographical distribution.
• Monitoring of human cases and potential exposure routes.

Main Results:

• 2514 HPAI A(H5) detections reported in European birds (406 domestic, 2108 wild).
• Over 90% of poultry detections linked to primary introduction from wild birds; waterfowl species significantly affected.
• Increased detections in mammals noted, including a potential spillover event to dairy cattle.
• 10 human avian influenza virus infections reported in Cambodia and China, with exposure to poultry environments.

Conclusions:

• HPAI A(H5) virus circulation in European wild birds remains a significant concern, impacting poultry and increasing mammal exposure.
• While human infections are rare and no human-to-human transmission is documented, the risk to occupationally exposed individuals is low-to-moderate.
• Continued surveillance and biosecurity measures are crucial to mitigate HPAI spread and potential zoonotic transmission.