dairy farm cows
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Dairy cows in several US states have reportedly contracted bird flu. United States Department of Agriculture (USDA). The virus has killed millions of birds around the world, but this is the first time it has been detected in cattle.
How many cows are affected by avian influenza?
As of March 25, milk samples from two dairy farms in Kansas and one in Texas tested positive for the avian influenza subtype called H5N1. new york times. This strain is highly lethal to birds. A cow throat swab taken from a dairy farm in Texas also tested positive. So far, no cows have died from the virus.
On March 22, U.S. authorities announced a diagnosis of avian influenza in bovines after some dairy cows at farms in Texas, Kansas, and New Mexico became ill and there were reports of dead wild birds on farm grounds. The inspection has started.
About 10% of the milking cows on the affected farms appear to be sick, most of them elderly. It is unclear whether avian influenza is the cause of all animal illness. U.S. authorities are moving quickly to conduct additional testing.
How did the cow become infected with the virus?
The Department of Agriculture announced that the cows appear to have contracted the virus from infected wild birds. However, it is unclear exactly how the virus was transmitted between species.
Most mammals that contract bird flu are carnivores, such as foxes and seals, who most likely contracted the virus by eating dead or infected birds.Because cows don’t eat birds, it’s difficult to explain the source of infection. Richard Webby at St. Jude Children’s Research Hospital in Tennessee. Feces and saliva from wild birds may have contaminated the cows’ water and feed.
“The biggest question that I don’t fully understand is how do you account for transmission across the state with such geographic spread,” Webby said.
The worst-case scenario is that the virus spreads among cattle, but that’s probably unlikely, he said. This is because there is still no evidence that avian influenza can be transmitted between mammals.
Do sick cows increase the risk of avian influenza spreading to humans?
The risk of contracting bird flu remains low for most people. Initial testing of samples taken from infected cows has found no genetic changes that would suggest the virus is more transmissible to humans.
But each time a mammal gets avian influenza, Webby says, it gives the virus a chance to acquire the mutations it needs to spread between mammals. “But to put this into perspective, we still need some answers. Above all, how many cows are showing evidence of being infected with the virus?” If there are very few, the virus is likely to become a dead end again, as it did in foxes, bears, and other previously infected animals.
Is milk safe to drink?
Yes, milk is still safe to drink. The USDA already requires dairy farms to send only milk from healthy cows for processing. Milk from infected cows is also being discarded and kept out of the food supply.
Even if contaminated milk enters the supply chain, pasteurization kills bacteria and viruses, including influenza.
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Source: www.newscientist.com
