Three human cases of bird flu have been detected in humans in the US amid an outbreak in dairy cattle.
ADVERTISEMENTHealth authorities identified a third human case of bird flu in the US amid an outbreak in dairy cattle.
The US Centers for Disease Control and Prevention (CDC) said this was the second human case of influenza A(H5N1) in the US state of Michigan. Another human case of bird flu was detected in Texas in April.
All three cases concerned dairy workers "with exposure to infected cows, making this another instance of probable cow-to-person spread," the CDC said, with no indication that it has been transmitted between people.
The most recent case was the first to have typical influenza symptoms, authorities added. The other two farm workers had only reported eye symptoms.
The risk to the general public is low, the CDC said, but "given the extent of the spread of this virus in dairy cows, additional human cases in people with higher risk exposures would not be surprising".
As of this week, there were 67 dairy cattle herds affected in nine US states.
US authorities have been testing dairy and meat samples to ensure the safety of the food supply.
In April, some 20 per cent of retail dairy samples were positive for viral fragments of bird flu, but the Food and Drug Administration (FDA) said that "additional testing did not detect any live, infectious virus".
Results of testing in May showed that pasteurisation was effective in deactivating the virus, the FDA said.
The situation in Europe and globally
There are no cases of A(H5N1) in humans or cattle in the EU, according to the latest communicable disease threats report from the European Centre for Disease Prevention and Control (ECDC).
Most of the cases of bird flu globally are a specific strain that emerged in 2020 and spread by migratory birds, according to a joint report from the Food and Agriculture Organization, the World Health Organization, and the World Organisation for Animal Health
Since 2021, there had been about 28 detections of A(H5N1) in humans reported to WHO, including two cases in Spain in 2022 and four cases in the UK in 2023.
The report also said there were increased detections of bird flu in non-bird species globally.
Authorities recommend that individuals exposed to infected animals wear appropriate protective items and take precautions to reduce infection.
Meanwhile, the Dutch agriculture ministry said this week that two bird flu vaccines were found to be effective in practice.
The government said 1,800 day-old chicks were vaccinated against bird flu in September 2023, with transmission tests showing the vaccines were effective eight weeks on.
"For the coming year and a half, we will continue doing these transmission tests to investigate the effectiveness of the vaccines during the entire laying period," a ministry spokesperson said.
