Four agricultural workers in Washington state have tested positive for bird flu, the first human cases of H5N1 virus to be reported in the state. Washington is the sixth state to report a human infection of avian flu.

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.

Slovakia has reported an outbreak of avian influenza on a poultry farm, the World Organisation for Animal Health (WOAH) said on Tuesday, as Europe faces a seasonal upturn in the deadly disease commonly known as bird flu.