At least one person in Texas has been diagnosed with bird flu after having contact with dairy cows presumed to be infected, state officials said on Monday.
The announcement adds a worrying dimension to an outbreak that has affected millions of birds and sea mammals worldwide and, most recently, cows in the United States.
So far, there are no signs that the virus has evolved in ways that would help it spread more easily among people, federal officials have said.
The patient worked directly with sick dairy cows, said Lara M. Anton, a spokeswoman for the Texas Department of State Health Services. “We have tested around a dozen symptomatic people who work at dairies, and only the one person has tested positive” for the virus, she said in an email.
The patient’s primary symptom was conjunctivitis; the individual is being treated with an antiviral drug and is recovering, according to the Centers for Disease Control and Prevention.
The Department of Agriculture announced the first cases in dairy herds in Texas and Kansas last week, and a few days later, in an additional herd in Michigan. Preliminary testing suggests that cows in New Mexico and Idaho may also be infected.