Laboratory tests by the US Department of Agriculture haven’t found any H5N1 bird flu virus in raw beef, but they are a good reminder why eating rare hamburgers can be risky.
As part of a suite of tests conducted to check safe food handling advice after the detection of H5N1 bird flu virus in dairy cattle, the USDA recently mixed a substitute virus into ground beef and then cooked patties at varying times and temperatures.
Researchers found none of the virus in hamburgers cooked to 145 degrees, roughly the temperature of a medium burger, or well-done burgers cooked to 160 degrees. They did, however, find some live virus in patties cooked to 120 degrees or rare, although the virus was present “at much, much reduced levels,” said Eric Deeble, acting senior adviser for highly pathogenic avian influenza at the USDA.
Whether that small amount of virus could make someone sick is still an unknown.
The USDA already advises consumers to cook ground beef to an internal temperature of 160 degrees, as measured with a food thermometer, to avoid infections from bacteria such as salmonella and E. coli, he noted.
“I don’t think that anybody needs to change any of the safe food handling or safe cooking practices that are already recommended,” Deeble said.
The USDA also announced $22 million in new government investments to protect animal health. The bulk of the funding will go to the Animal Disease Preparedness and Response Program and to a network of state laboratories called the National Animal Health Laboratory Network.
“There are some labs that have equipment that needs to be updated or upgraded and additional folks that are interested in adding capacity to the laboratories that they operate. And so this funding is going to help support those types of projects,” Deeble said Thursday.
Between May 6 and May 12, the national lab network processed 1,100 tests for H5N1 bird flu in cattle, and 278 of those were presumed positive, Deeble said. He cautioned that because multiple samples can be taken from the same animal or tests may be pooled, the number of tests doesn’t reflect the number of animals tested or the number that are positive. Approximately 600 of the tests were performed in accordance with the USDA’s new order, which requires testing of dairy cattle moving between states. Another 450 tests were performed on animals showing symptoms.
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USDA said that it had gotten a positive response to its offer last week to financially compensate producers who take steps to protect their herds and workers against further spread of the virus. However, it doesn’t have the forms ready for farmers to fill out, so nobody has been signed up for the program. It hopes to have the paperwork ready by the middle of next week, Deeble said.
Dr. Nirav Shah, principal deputy director of the US Centers for Disease Control and Prevention, said the agency had not been able to find farmworkers willing to participate in studies looking at how bird flu transmits on dairy farms in return for $75.
“We’re not giving up hope. We are in constant conversation with a number of states. We’re getting closer, but as of yet, nothing across the finish line,” Shah said.