In response to the threat posed by highly pathogenic avian influenza (HPAI) H5N1, the USDA has announced proactive measures aimed at safeguarding the nation's livestock industry. The actions, in collaboration with other federal partners, are designed to curb the spread of the disease.
USDA’s Animal and Plant Health Inspection Service (APHIS) announced a federal order requiring the following measures, effective Monday, April 29, 2024:
Mandatory testing for interstate movement of dairy cattle
- Dairy cattle are required to receive a negative test for influenza A virus at an approved National Animal Health Laboratory Network (NAHLN) laboratory prior to interstate movement.
- Owners of herds in which dairy cattle test positive for interstate movement will be required to provide epidemiological information, including animal movement tracing.
- Dairy cattle moving interstate must adhere to conditions specified by APHIS.
- These steps will be immediately required for lactating dairy cattle, while these requirements for other classes of dairy cattle will be based on scientific factors concerning the virus and its evolving risk profile.
Mandatory reporting
- Laboratories and state veterinarians must report positive influenza A nucleic acid detection diagnostic results (e.g., PCR or genetic sequencing) and positive influenza A serology diagnostic results in livestock to APHIS.
The USDA has identified various transmission routes, including spread from cow to cow within herds, from cows to poultry, and between dairies associated with cattle movements. Cows without the clinical signs of decreased milk production; reduced appetite; thickened, discolored milk; lethargy; and/or dehydration have also tested positive.
Recent findings suggest potential adaptation of the virus to mammals, though the overall risk to the public remains low, according to the Centers for Disease Control and Prevention (CDC). Additionally, affected cows continue to recover after supported care with little to no associated mortality.
According the release from the USDA, “This federal order is critical to increasing the information available for USDA. Requiring positive test reporting will help USDA better understand this disease and testing before interstate movement will limit its spread.”
Commercial milk supply remains safe
On Tuesday, the FDA reaffirmed that pasteurization of milk consistent with the federal Grade “A” Pasteurized Milk Ordinance (PMO) destroys harmful pathogenic bacteria and other microorganisms, including HPAI and other viruses. Further, the PMO requires the diversion or destruction of milk from sick cows.
The USDA, the FDA and other federal partners continue to work closely to collect and evaluate additional data and information specific to HPAI in dairy cattle as continued scientific vigilance and collaboration are vital in managing the evolving situation.
