A microbiologist tests poultry samples collected for the presence of avian influenza, or bird flu, at the Wisconsin Veterinary Diagnostic Laboratory at the University of Wisconsin-Madison on March 24, 2022 in Madison, Wisconsin. (Scott Olson/Getty Images)
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.
The cases, if confirmed, would be the first time people in Washington have contracted the virus since officials began tracking a notable rise of it in birds and other animals starting in the U.S. around 2022 . Since then, upwards of two dozen human cases have been detected across five other states — all but one tied to people coming into contact with infected animals.
Health officials emphasized that the four positive cases in Washington are “presumptive,” pending final confirmation and analysis by the U.S. Centers for Disease Control and Prevention.
“We are still going through the ongoing investigation,” Dr. Umair Shah, Washington’s secretary of health, said during an online press conference on Sunday. “At this time, we believe the individuals that we have gotten the results back have been exposed to infected poultry. We do not have evidence at this time of human-to-human spread. However, that is still part of our investigation.”