Dairy cows in a number of US states have fallen unwell with fowl flu, in line with the US Department of Agriculture (USDA). The virus has killed hundreds of thousands of birds worldwide, however that is the primary time it has been detected in cattle.

What number of cows are affected by fowl flu?

As of 25 March, milk samples collected from two dairy farms in Kansas and one in Texas have examined optimistic for a subtype of avian influenza referred to as H5N1, in line with The New York Times. This pressure is very deadly in birds. A cattle throat swab taken from a dairy farm in Texas additionally examined optimistic. No cows have died from the virus to this point.

US companies started testing cattle for fowl flu on 22 March after farms in Texas, Kansas and New Mexico reported some dairy cows had fallen unwell, and that lifeless wild birds have been on their properties.

On the affected farms, about 10 per cent of milking cows seem like sick, most of whom are older. It’s unclear if fowl flu is accountable for the entire animals’ sicknesses. US companies are transferring rapidly to conduct further testing.

How did the cows catch the virus?

The USDA says it seems the cattle caught the virus from contaminated wild birds. Nevertheless, it’s unclear precisely how the virus transmitted between the species.

Most mammals who fall unwell with fowl flu are carnivores, resembling foxes or seals, which means they more than likely contracted the virus from consuming lifeless and contaminated birds. As cows don’t eat birds, it’s tougher to elucidate the supply of transmission, says Richard Webby at St. Jude Youngsters’s Analysis Hospital in Tennessee. It might be that faeces or saliva from wild birds contaminated the cattle’s water or meals.

“The most important query I can’t fairly get my head round is the right way to clarify infections throughout such a geographic unfold of states,” says Webby.

The worst-case state of affairs is the virus unfold among the many cows, however that is maybe unlikely, he says. That’s as a result of we haven’t discovered proof that fowl flu can transmit between mammals.

Do the sick cows improve the chance of fowl flu spreading to folks?

The chance of contracting fowl flu stays low for most individuals. Preliminary testing of samples from contaminated cattle haven’t discovered genetic adjustments that might counsel the virus has turn out to be extra transmissible to people.

But any time a mammal turns into unwell with fowl flu, it offers the virus a chance to realize the mandatory mutations to transmit between mammals, says Webby. “However we nonetheless want some solutions to place this into perspective: most of all, what number of cows present proof of being contaminated with the virus?” If few cows are unwell, this can more than likely be one other lifeless finish for the virus, very like foxes, bears and different beforehand contaminated animals have been.

Is milk secure to drink?

Sure, milk continues to be secure to drink. The USDA already requires that dairy farms solely ship milk from wholesome cattle in for processing. Milk from contaminated cows has additionally been destroyed so it gained’t enter the meals provide.

Even when some contaminated milk entered the provision chain, pasteurisation kills micro organism and viruses, together with influenza.