That brings the total in the United States to nine since the first human case of the current outbreak was detected in 2022, also in a Colorado poultry worker. Eight of the nine were reported this year.
Their illnesses were relatively mild — reddened and irritated eyes and common respiratory infection symptoms such as fever, chills, coughing, sore throat and runny nose.
None were hospitalized, officials said.
A fifth person with symptoms is undergoing testing; results are not yet completed.
The workers were culling poultry at a farm in northeast Colorado, according to state health officials. All had direct contact with infected birds.