
Highly pathogenic avian influenza
Highly pathogenic avian influenza (HPAI) is a highly contagious transboundary disease with zoonotic potential affecting both animal and human health. It causes variable clinical signs and high mortality rates in both wild and domestic bird populations. Current H5 AI outbreaks have severely impacted countries globally, causing losses of rare and important wild bird species, as well as significant social and economic costs, including livelihood losses and egg shortages.
The spread of HPAI also strains poultry-related businesses, as measures such as culling and movement restrictions are necessary to contain the virus, which can disrupt the trade of poultry products. The ongoing devastation highlights the urgent need for improved control measures to prevent spillover and viral changes that could lead to a global pandemic. HPAI also infects mammals and humans, posing serious public health risks. Infected mammals include domestic cats, cattle, and wild animals such as foxes and seals, with human cases, although rare, occurring in those with close contact with infected poultry or environments.
Addressing these challenges requires a robust One Health approach. The FAO’s One Health Programme Priority Area (OHPPA), specifically the Better Production 3 (BP3) program, focuses on enhancing productivity and mitigating zoonotic infections risks like HPAI. It aims to strengthen early warning systems, improve biosecurity measures, and enhance preparedness and response to food chain emergencies. By promoting sustainable and inclusive food and agriculture supply chains, BP3 helps ensure resilient agrifood systems, while mitigating the impacts of HPAI.
FAO's role
Since 2004, FAO has worked globally to combat avian influenza (AI) by promoting biosecurity, improving disease control, and enhancing laboratory diagnostic capabilities through the One Health approach. In partnership with FAO/WOAH Reference Laboratories and other organizations, FAO monitors and assesses AI risks, providing laboratory protocols and sharing vital epidemiological and virological findings. FAO regularly issues updates on transboundary and emerging diseases, including AI, offering technical guidance and response recommendations.
Through the WOAH/FAO Network of Expertise on Animal Influenza (OFFLU), FAO coordinates efforts to prevent, detect, and control animal influenzas and collaborates with WHO on pandemic preparedness and risk assessment.
Did you know?
⦿ HPAI virus has spread worldwide and become endemic in poultry populations in many countries.
⦿ Since 2003, HPAI has led to the culling of hundreds of millions of birds worldwide to control outbreaks.
⦿ Outbreaks of HPAI have caused billions of dollars in economic losses due to the death of poultry, trade restrictions, and control measures.
⦿ The most notable subtypes of HPAI include H5N1, H7N9, and H5N8.
⦿ Surveillance and monitoring are essential for early detection and response to HPAI outbreaks.
Frequently asked questions

Stay informed on the current HPAI situation, latest outbreaks, risks, and essential measures for prevention and control.
Situation updates
Featured resources

Elearning
Introduction to avian influenza: self-paced course
Tailored for veterinaries, veterinary paraprofessionals, and industry experts, this course provides crucial knowledge on global impact, detection methods, and prevention strategies.
Publication
Global strategy for the prevention and control of high pathogenicity avian influenza (2024–2033)
In response to the escalating threat of high pathogenicity avian influenza (HPAI), FAO and WOAH have launched a revised global strategy...
Publication
Recommendations for the surveillance of influenza A(H5N1) in cattle
As influenza A(H5N1) of clade 2.3.4.4b continues to spread from wild birds to poultry and to both terrestrial and marine mammals, the recent cases in cattle highlight the...
Publication
Updated joint FAO/WHO/WOAH public health assessment of recent influenza A(H5) virus events in animals and people
During 2020, high pathogenicity avian influenza (HPAI) A(H5N1) clade 2.3.4.4b viruses arose...
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News
The spread of H5N1 highly pathogenic avian influenza calls for stepped up action, FAO says
The spread of H5N1 highly pathogenic avian influenza, bringing losses of hundreds of millions of poultry worldwide with increased spillover into mammals, highlights the urgent need for strengthened biosecurity...

News
FAO presents recommendations in response to the reappearance of highly pathogenic avian influenza in Latin America and the Caribbean
In light of the recent increase in cases in several countries in the region, FAO has released a new document outlining lessons learned and challenges...

News
Shaping global vaccine strategies to combat zoonotic influenza
Zoonotic influenza – the type of flu that jumps from animals to humans – is a growing global concern. Recent human infections with H5 avian influenza and its spread into mammalian populations highlight the urgent need for action. That's where the WOAH/FAO...