Bird flu has been detected in beef for the first time, the U.S. Department of Agriculture announced Friday, but officials said the meat from a single sickened dairy cow was not allowed to enter the nation’s food supply and beef remains safe to eat.

The USDA said the virus was found as part of testing of 96 dairy cows that were diverted from the supply because federal inspectors noticed signs of illness during routine inspections of carcasses at meat processing plants. Bird flu was found in only one of those cows.