High Pathogenicity Avian Influenza in Cattle

The ongoing spread of High Pathogenicity Avian Influenza (HPAI) in different regions of the world, alongside the recent detections of cases in cattle, is raising concerns within the international community.

While HPAI primarily affects poultry and wild birds, avian influenza can occasionally be transmitted to mammals, including humans. In the last two years, an increasing number of H5N1 avian influenza cases have been reported in terrestrial and aquatic mammalians animals.

The recently reported detections of HPAI in dairy cattle in the United States of America, showing clinical signs such as decreased lactation, reduced appetite, lethargy, fever and dehydration, have raised concerns since such infections of cattle could indicate an increased risk of H5N1 viruses becoming better adapted to mammals, and potentially spilling over to humans and other livestock.  

Initial investigations so far have revealed no specific adaptation to either humans or mammals. Regardless, several studies are being carried out to further explore the virulence and transmissibility of these viruses, including among cattle, and to assess the risk of transmission to animals and humans, which is currently considered very low.  

In collaboration with its Reference Centres, OFFLU networks of experts and Members, the World Organisation for Animal Health (WOAH) is closely monitoring the situation to assess the risks to animals and humans. Timely and transparent reporting is crucial to maintain a good understanding of the disease situation and prevent any type of misinformation or disinformation. 

WOAH reminds its 183 Members that, based on the information currently available, restrictions on the movement of healthy cattle and their products are not recommended unless justified by an import risk analysis conducted according to the WOAH Terrestrial Animal Health Code Chapter 2.1.  

WOAH calls on its Members to: 

• Maintain enhanced avian influenza SURVEILLANCE in domestic and wild birds.  
• MONITOR and INVESTIGATE the cases in non-avian species, including cattle and other livestock populations showing clinical signs compatible with avian influenza.  
• REPORT cases of HPAI in all species, including unusual hosts, to WOAH through its World Animal Health Information System (WAHIS). Genetic sequences of avian influenza viruses should be shared in publicly available databases. 
• PREVENT the introduction and spread of the disease by implementing strict biosecurity measures in livestock holdings and employing good production practices when handling animal products such as raw milk and meat from suspected or confirmed cases.  
• PROTECT humans in close contact with or handling sick cattle or other sick livestock and their products. Exposed humans should always take precautionary measures, including wearing personal protective equipment and implementing standard food safety measures when handling  animal products from exposed livestock.  
• AVOID implementing unjustified trade restrictions. Import risk management measures should be scientifically justified and in line with the WOAH International Standards.

WOAH is fully committed to supporting its Members to mitigate risks against the impact of avian influenza. We will continue to engage with our networks of experts as well as public and private partners, notably through the One Health Quadripartite and the Global Framework for Transboundary Animal Diseases (GF-TADs) to provide technical updates as more information becomes available.