After a U.S. Department of Agriculture inspector saw a suspicious lesion on a cow in Washington state, testing of the tissue identified bovine tuberculosis, and officials are confirming the results with a second test. There is no threat to human health, since the cow was removed from the food chain and milk from its dairy is pasteurized, which kills the pathogen, according to a state agriculture official. The dairy has been quarantined until 1,500 of its cattle can be tested for the disease, although bovine TB usually only surfaces in 1% to 4% of cows in close proximity to an infected cow, the official said.