Cooking temperatures sufficient to kill H5N1 in meat

Ground beef patties, that did not previously contain any virus particles, were inoculated with a very high concentration of an H5N1 virus surrogate. The burger patties were then cooked to three different temperatures (120, 145 and 160 degrees Fahrenheit), and virus presence was measured after cooking. There was no virus present in the burgers cooked to 145 (medium) or 160 (well done) degrees, which is FSIS’ recommended cooking temperature. Even cooking burgers to 120 (rare) degrees, which is well below the recommended temperature, substantially inactivated the virus. The USDA says these results validate that FSIS’ recommended cooking temperatures are sufficient to kill H5N1 in meat.

The ground beef cooking study is one of three separate beef safety studies USDA is conducting following the detection of avian influenza in dairy cattle.

On May 1, FSIS announced results from its testing of retail ground beef, after collecting 30 samples of ground beef from retail outlets in states with dairy cattle herds that had tested positive for the H5N1 influenza virus. The samples were sent to APHIS’ National Veterinary Services Laboratories for polymerase chain reaction testing. NVSL reported that all samples tested negative for H5N1.

The final study will involve beef muscle sampling of cull dairy cows condemned at select FSIS-inspected slaughter facilities: FSIS is currently collecting muscle samples at FSIS-inspected slaughter facilities of cull dairy cattle that have been condemned for systemic pathologies. The samples will be analyzed by APHIS using PCR to determine presence of viral particles.

According to a FSIS spokesperson, results from these studies are forthcoming and information will be shared as it becomes available. However USDA is confident that the meat supply is safe.

"USDA has a rigorous meat inspection process, where USDA’s Food Safety and Inspection Service veterinarians are present at all federal livestock slaughter facilities. FSIS inspects each animal before slaughter, and all cattle carcasses must pass inspection after slaughter and be determined to be fit to enter the human food supply. While we have multiple safeguards in place to protect consumers, we recommend consumers properly handle raw meats and cook to a safe internal temperature. Cooking to a safe internal temperature kills bacteria and viruses in meat."