United States: Colorado’s second poultry facility has been hit by bird flu in a worker, making it the seventh human case in the state this month as avian influenza ravages dairy cows.
More about the news
Colorado health officials said the seventh case is, however, still presumptive positive. This means that the person has come out positive at the state level as authorities continue to conduct an outbreak test at the Centers for Disease Control and Prevention (CDC).
A presumptive positive worker was reported at a poultry facility in northeastern Weld County. H5N1 virus, which is associated with bird flu, has been identified in the plant as six workers of Weld tested positive for the virus in the past couple of weeks at another.
At that place, a commercial egg layer farm comprised nearly 1.8 million birds. Many of the workers got infected as they were engaged in the process of culling birds that were positive to the highly pathogenic avian influenza (HPAI), as arstechnica.com reported.
Genetic testing of the virus was conducted on the birds and the workers, and the results showed that they contracted a strain of H5N1 similar to the one emerging in dairy cattle and affecting workers on dairy farms.
Transmission of virus to humans
The US Department of Agriculture, USDA, only late in March admitted that the H5N1 bird flu virus that had been infecting wild birds across the globe for years had crossed over to dairy cows in the US.
Data show that at least 168 herds in thirteen states have been confirmed to have contracted the virus.
It was during the outbreak of the dairy that eleven humans were affected by the virus. Four of the cases were among dairy workers, of which there is one in Texas, two in Michigan, and one in Colorado, which had been reported earlier this month.
Seven other cases were among poultry workers, all from Colorado. There was also a human H5N1 case in a Colorado poultry worker in 2022; before the virus mutated and infecting cows, as arstechnica.com reported.
The most recent case is the appearance of human infections among poultry workers in Colorado, which is rather revealing, considering that H5N1 has impacted US poultry farms since January 2022.
So far, outbreaks have been registered in 48 states, and more than a hundred million birds have been infected. In most of those cases, direct transmission of bird-to-bird contact from wildlife thought to be carriers of avian influenza is assumed in poultry, which is considered to be highly vulnerable to attack.
However, cases of poultry workers have slowly and steadily started increasing only when the virus switched from wild birds to dairy cows and poultry.
Genetic sequencing up to now has not identified large shifts in the virus that would be potentially associated with the recent surge, or which would present fresh cause for concern.
Still there is no reports of transmission of the disease from one person to another, and according to the CDC the threat of the H5N1 to the average person is negligible.
Moreover, all the human cases reported so far have been mild, and clinical signs suggest that they can be treated with flu antivirals.
What does the official explain?
Federal officials state that human cases have increased, and excessive summer heat is to blame.
Poultry workers in Colorado who were charged with culling birds had to deal with temperatures touching over 100° Fahrenheit and noisy industrial fans blowing in the background. This causes a struggle to keep wearing the mask and goggles on their faces.
However, it is not yet understood how this virus is transmitted from dairy farms to poultry farms during this latest phase of the spread.