The worker are the first presumed human cases of highly pathogenic avian influenza, H5N1, under investigation in Washington state, the Washington state Department of Health said Sunday. The workers have had mild symptoms and have been offered antiviral medication by the Benton Franklin Health District. None have required hospitalization.

The CDC is deploying a team to Washington state to assess the health of farm workers who culled poultry suffering from bird flu after four workers are presumed to have been infected by the virus, U.S.

Officials in Washington are investigating the state’s first-ever presumed human cases of avian influenza after four agricultural workers tested presumptively positive for the disease, the