Following test results from the Washington State Department of Agriculture on Oct. 15, about 800,000 birds had to be euthanized. The DOH said these are the first presumed human cases of H5 virus ...

Persistent human-to-human transmission would be an indication of a larger public health risk, they said. "This is an evolving situation. We are continuing to monitor the situation closely," Shah said.

Washington state health officials are investigating after four agricultural workers tested presumptively positive for bird flu, marking the first presumed human cases in the state, the Washington ...