In recent developments reported by the World Organisation for Animal Health (WOAH), the spread of High Pathogenicity Avian Influenza (HPAI) has taken an alarming turn with detections in unexpected hosts. While traditionally affecting poultry and wild birds, the virus has now been found in dairy cattle in the United States, raising significant concerns among global health officials.
Avian influenza strains, particularly H5N1, have shown an increasing trend of infecting terrestrial and aquatic mammals over the past two years. This shift in host susceptibility is a worrying sign, indicating a potential adaptation of the virus to mammalian hosts. Although current evidence does not suggest specific adaptations to humans, the situation necessitates vigilant monitoring and preventive measures.
The detected cases in cattle have shown varied clinical presentations, from asymptomatic carriers to mild illness marked by decreased milk production, thicker milk consistency, and other non-specific symptoms such as reduced appetite and fever. Importantly, raw milk from infected cows poses a notable risk, highlighting the need for stringent controls over dairy products to prevent potential transmission routes to other animals and humans.
In response to these developments, WOAH has issued urgent recommendations to its 183 member countries. Enhanced surveillance measures for avian influenza in both domestic and wild bird populations are advised, alongside considering HPAI as a differential diagnosis Veterinary Rapid Test in non-avian species showing compatible symptoms. Timely reporting of any suspected cases to WOAH’s World Animal Health Information System (WAHIS) is emphasized to ensure a coordinated global response.
Furthermore, strict biosecurity measures and adherence to good production practices are crucial in preventing the spread of the virus in livestock settings, especially in milking parlors. Vaccination of poultry is also recommended as a complementary control measure against avian influenza.
In light of these developments, WOAH urges its members against implementing unjustified trade restrictions, advocating instead for scientifically justified import risk analyses based on international standards. This approach aims to balance public health protection with the continuity of safe international trade.
As the situation evolves, WOAH pledges to continue collaborating closely with its network of experts, including OFFLU, Bio-FAST and other public-private partnerships under the One Health framework. Regular updates and technical guidelines will be provided to support global efforts in mitigating the risks associated with avian influenza and safeguarding both animal and human health worldwide.
Protect Yourself From H5N1 When Working With Farm Animals (PDF)