USDA’s Food Safety and Inspection Service (FSIS) has conducted tests on beef tissue from 96 cull dairy cows condemned at select FSIS-inspected facilities. On May 22, 2024, viral particles were detected in tissue samples, including muscle, from one cow. To date, samples from 95 cows have tested negative for viral particles. No meat from these dairy cattle entered the food supply.
As part of this study, FSIS collected multiple tissues, including muscle samples from the diaphragm, at FSIS-inspected slaughter facilities from cull dairy cattle condemned for systemic diseases. The samples were analyzed by APHIS using PCR to determine the presence of viral particles. PCR testing does not differentiate between live virus or fragments.
FSIS and APHIS are working together to conduct traceback, including notification to the producer to gather further information.
FSIS personnel identified signs of illness in the positive animal during post-mortem inspection and prevented the animal from entering the food supply. This type of inspection is part of routine FSIS operations. These actions provide further confidence that the food safety system is functioning effectively.
Further updates will be provided as testing is completed.
USDA is confident that the meat supply is safe. USDA has a rigorous meat inspection process, which includes FSIS veterinarians who are present at all federal livestock slaughter facilities. FSIS personnel inspect each animal before slaughter, and all cattle carcasses must pass a second inspection after slaughter and be determined fit to enter the human food supply.
While multiple safeguards are in place to protect consumers, USDA continues to recommend proper handling of raw meats and cooking to a safe internal temperature. Cooking to a safe internal temperature kills bacteria and viruses in meat. Specific recommendations are available online at: Safe Minimum Internal Temperature Chart | Food Safety and Inspection Service (usda.gov).
To verify the safety of the meat supply in the context of H5N1, USDA’s FSIS, APHIS, and Agricultural Research Service (ARS) are working on three separate beef safety studies related to avian influenza in meat from dairy cattle. These studies aim to reaffirm consumer confidence through scientific inquiry.
FSIS completed collection of muscle samples at FSIS-inspected slaughter facilities from cull dairy cattle condemned for systemic disease. No meat from these dairy cattle entered the food supply. The samples were analyzed by APHIS using PCR to determine presence of viral particles.
To date, testing has been completed on 96 out of 109 muscle samples collected. As of May 22, no viral particles were detected in 95 samples for which testing has been completed. NVSL reported that viral particles were detected in tissue samples, including diaphragm muscle, from one cow.
FSIS and APHIS are working together to conduct traceback, including notification to the producer to gather further information.
FSIS personnel identified signs of illness in the positive animal during post-mortem inspection and prevented it from entering the food supply – as is standard for the food inspection process. These actions provide further confidence that the food safety system is effective.
Samples of ground beef obtained at retail outlets in affected states showed no virus particles present upon analysis by APHIS using PCR.
A ground beef cooking study by ARS inoculated a high level of an H5N1 Influenza A virus into ground beef patties to determine whether FSIS recommended cooking temperatures are effective in inactivating H5N1 virus. The patties were cooked to three different temperatures (120°F, 145°F, and 160°F), with no virus present in burgers cooked to 145°F or 160°F—FSIS’ recommended cooking temperature—and substantial virus inactivation even at 120°F.
