By Leah Douglas
WASHINGTON (Reuters) -The U.S. Centers for Disease Control and Prevention on Thursday confirmed two of four presumptive positive cases of bird flu among workers at poultry farms in Washington state.
The agency also ruled out bird flu infections among health care workers who cared for a person who contracted the virus in Missouri, officials said in a press call.
All 31 confirmed human cases of bird flu in the U.S., but the one in Missouri, involved farmworkers who had contact with infected poultry or dairy cows. Officials have said the risk to the general public from bird flu remains low.
The CDC expects the number of confirmed cases in Washington to rise as it completes confirmatory testing of additional presumptive positive results, Deputy Director Nirav Shah said on the call.
Serology tests of health care workers who came into contact with the sick person in Missouri showed they were not infected with bird flu, a CDC official said on the call.
The agency’s investigation in Missouri ruled out person-to-person spread, but some tests of a household contact of the sick person suggested infection, officials said. The agency suspects both people may have been exposed to a sick animal they could not identify.
The CDC has sent teams to California, Michigan, Colorado and Washington to help with the bird flu response, Shah said.
