Doctors are raising concerns about a mutated form of bird flu that has infected a farm worker in Texas.
The patient contracted the virus, which caused his eyes to become red and itchy, through contact with an infected dairy cow or chicken in Texas.
Government-backed researchers took a sample of the virus, infected mice and ferrets with it, and discovered that it had evolved to be far deadlier than the wild strain currently spreading on American farms.
It also spread between animals through the air, a major milestone that could theoretically allow it to be more contagious in humans.
But crucially, the tests showed that some antiviral drugs could work against this strain of the virus if this is the case.
The experts are now warning health officials to keep a closer eye on the movement of the virus, to contain the outbreak before it can evolve further and infect more people.
Of the research, government officials said: ‘These mutations underscore the need for continued monitoring and evaluation of viruses resulting from the current H5N1 outbreak.’
So far in 2023, 34 people in the US have been infected with bird flu, 33 of which have been linked to contact with infected cows or poultry.
The above image of the symptoms suffered by the Texas dairy farmer who contracted bird flu was published in the New England Journal of Medicine
Your browser does not support iframes.
The virus is not known to be transmissible between people. Yet an unidentified Missouri man contracted the disease without ever having contact with an infected animal.
Researchers have suggested that drinking unpasteurized milk from an infected cow or raw egg from an infected chicken could also spread the virus.
Bird flu has rocked the US in recent months, hitting Texas, New Mexico and Missouri.
It causes red, itchy eyes and mild respiratory symptoms.
Last week, the bodies of dairy cows piled up in California as farmworkers tried to contain the spread of the disease, which affected 124 herds of dairy cows.
In the new paper, researchers funded by the National Institute of Allergy and Infectious Diseases (NIAID) took a sample of the H5N1 virus from the eye of a Texas dairy worker who was infected with the disease to see how it affects animals in the would affect the future. laboratory.
They tested it in both mice and ferrets and noted that ferrets tend to have a similar response to the flu virus as humans.
They published their findings as a pre-print, meaning it still needs to be reviewed by other scientists, in the magazine Nature.
They found that the virus had mutated and could pass through the air, affecting between 17 and 33 percent of ferrets in neighboring cages.
Dead cows are piling up in California as dairy farmers battle the H5N1 bird flu, which made landfall in the state in August
The study also compared how much of the huTX37-H5N1 strain was needed to kill a mouse, and compared this to an unmutated H5N1 strain from a study published in Nature in July.
It turned out that to kill a mouse, they needed less than one unit of the huTX37-H5N1 virus, compared to 31.6 units of the H5N1 virus in July.
This suggests that the mutated virus could be 30 times more potent than older strains.
Within a week of being directly infected with the virus, all ferrets that researchers directly infected with the virus died from the disease. It is unclear whether the animals that contracted the virus from the air have died.
Currently, researchers say that people can only get the virus if they come into direct contact with bodily fluids from an infected animal.
But if the virus can spread through the air, it has the potential to infect many more people.
The NIAID study did find that some antiviral medications could stop the symptoms of the virus, including some, such as Xofluza, that are already on the market.
The study authors said: ‘Based on these observations, every effort should be made to limit HPAI H5N1 outbreaks in dairy cattle to limit the potential for further human infections.’