Conforming to the well-established principle of “too little-too late” the USDA-APHIS has eventually reacted to the concerning incidence rate of bovine influenza-H5N1. On December 6th the Agency issued a Federal order together with guidance requiring nationwide sampling of raw milk at farm, processing and distribution levels to detect herd infection with bovine influenza H5N1.
Recognized in March 2024 and present since December 2023, bovine influenza-H5N1 is not simply a “cow disease”. The infection has zoonotic potential as evidenced by clinical symptoms and serologic evidence of infection among workers. The presence of bovine influenza H5N1 is also implicated in transmission of infection to poultry flocks in Colorado, California, Michigan and Utah.
The federal order requires:-
- Sharing raw milk samples on request from dairy farmers, bulk milk transporters, transfer stations, and processing facilities that hold milk intended for pasteurization.
- Herd owners demonstrated to have infected animals must provide epidemiologic information for contract tracing and surveillance.
- Private laboratories and state veterinarians must report positive results to the USDA.
The program of milk testing by herd was initiated by both Colorado and California months ago. Surveillance was instrumental in reducing the rate of infection in Colorado that suffered extensive losses among poultry flocks attributed to spillover from dairy farms. The situation in California is more complicated with an increasing incidence among dairy herds, especially in the Central Valley, a region of intensive production.
USDA-APHIS maintains that the Agency has “taken significant steps to better understand and control the viruses spread.” This self-adulatory comment is questioned given that individual states have taken the initiative to implement surveillance programs six months before the current Federal directive. It is acknowledged that in April, USDA issued a federal order requiring milk testing to be conducted before movement of lactating cows from affected herds across state lines. This did nothing to prevent transmission of infection within state nor did it establish quarantines that would have prevented interstate movement of heifers nor movement of affected culled cows to processing facilities with the potential for dissemination of the virus.
It is indeed fortunate that pasteurization destroys H5N1 virus in milk and thorough cooking of meat from infected animals will prevent foodborne transmission of the virus. It is recognized that USDA-APHIS limited authority on policy and regulations relating to prevention of disease within states, but leadership both from a scientific and regulatory perspective has been soundly lacking.
In a statement accompanying the release of the Federal order, Secretary of Agriculture Tom Vilsack stated, “This will give farmers and farm workers better confidence in the safety of the animals and ability to protect themselves and it will put us on a path to quickly controlling and stopping the viruses spread nationwide.” Again too-little-to-late.