Researchers Verify That Mammal-to-Mouse Transmission of Bird Flu Has Started
Bird flu is persistently spreading between mammals, as health officials have long believed, raising the possibility of long-lasting outbreaks affecting people in the future.
Diego Diel, a virologist at Cornell University, says, "This is one of the first times that we are seeing evidence of robust and sustained mammalian-to-mammalian transmission."
Since 2022, the extremely deadly H5N1 virus B3.13 strain has resulted in the eradication of 90 million domestic birds in the United States alone. As just 11 people in the US have contracted the H5N1 strain thus far, the CDC reports that there is now little risk to the general public from this strain.
However, a single confirmed case of the similar H5N2 virus in Mexico killing a susceptible person serves as a sobering reminder of the dangers in case the disease changes.
H5N1's capacity for stealing genes from other influenza viruses and its ease of transitioning between other mammalian species are the main causes of concern over its potential. Mammals from the Arctic to the Antarctic have now been shown to carry it, including goats, wolves, otters, squirrels, dolphins, animal seals, and Antarctic fur seals.
First identified by DNA sequencing from a Canada geese (Branta canadensis) in Wyoming on January 25, 2024, was the strain responsible for the US dairy cow outbreak. The migratory bird flyway in Central North America is where the goose was discovered. This strain of the virus had spread to cows on dairy farms in several states along the same flyway by March 25, 2024.Following the interstate transportation of seemingly healthy dairy cattle from an impacted farm to a place distant from the flyway, genetic testing verified the occurrence of cow-to-cow dissemination. The biological information also showed that the infection spread in multiple directions, most likely as a result of cats and a racoon eating raw milk from sick cows.
Authorities from all around the world are advising people to practice proper hand hygiene and general hygiene when they are in areas where wild birds are present.
There have been no confirmed cases of H5N1 in Australia or New Zealand thus far. Both nations, however, are preparing for its unavoidable arrival and the catastrophic damage it is expected to cause to their distinct wildlife populations. Due to H7 bird flus, Australia is also currently experiencing a huge culling of poultry, which is leading to a significant shortage of eggs.
To lessen the impact on this highly endangered bird, the US has resorted to vaccinating California condors; nevertheless, assistance for numerous other species is likely to be required as well.
In the meantime, intense research is being done to create a vaccine for humans.
The USDA now mandates that dairy cattle test negative for the virus before they can be transferred into other states in response to the spread of H5N1 in dairy cows.
This discovery underscores the importance of enhanced monitoring and biosecurity measures to prevent potential outbreaks in other animals and humans. Ongoing research and vigilance are crucial to understanding and managing this evolving threat.
