Amid an uptick in H5N1 detections in dairy cows and poultry, the USDA has confirmed an outbreak at a broiler farm in the same Central Valley area that has been hit hard by outbreaks in dairy cows. The virus was detected at a broiler facility in Tulare County that has 786,600 birds.

Four agricultural workers in southeast Washington have preliminarily tested positive for bird flu after working around an infected poultry flock at a commercial egg farm.

Health officials are investigating the first presumed human cases of bird flu in Washington state after four agricultural workers tested positive for H5N1 last week. Why it matters: These are Washington's first presumed human cases of avian flu,