A dairy farm worker in Colorado has been infected with H5N1 bird flu, becoming the fourth human case in the outbreak so far.
The patient, who was not named, only had symptoms in their eye — such as reddening or swelling — and has since recovered from the infection.
They were treated with oseltamivir, an anti-viral used to treat flu infections. It was also used in previous cases.
Revealing the case in a release today, the CDC said it does not shift their assessment that the risk to the public from bird flu is low.
It is the fourth human case of human bird flu to be diagnosed in the US this year amid an outbreak of the virus in dairy cows, after a case was detected in Texas in April, and two cases in Michigan diagnosed in May.
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The farmer worked with dairy cattle confirmed to be infected with H5N1, with the individual likely catching the disease on the farm.
CDC scientists confirmed the diagnosis after receiving samples from Colorado’s state laboratories, where tests for common viruses were ‘inconclusive’.
They have already confirmed the patient is infected with an H5 virus, with confirmation that the case is H5N1 — or bird flu — expected in the coming days.
Further tests have also been ordered on the samples to check for any worrying genetic changes.
The CDC said in a release: ‘Based on the information available at this time, this infection does not change CDC’s current H5N1 bird flu human health risk assessment for the US general public, which the agency considers to be low.
‘However, this development underscores the importancee of recommended precautions in people with exposure to infected animals.’
Recommended precautions include the use of gloves, goggles or face masks while working with herds known to be infected with the virus.
Overall, 136 herds across 12 states now have confirmed infections with the bird flu virus.
