Cows within the UK are usually not being examined for hen flu, regardless of the outbreak sweeping by American dairy herds, Sky News has been advised.

The Department for Environment, Food and Rural Affairs (Defra) stated experiences of the H5N1 virus in UK birds and poultry are at present so low that it doesn't contemplate cattle to be in danger.

Scientists imagine the H5N1 virus has been spreading in US dairy herds undetected for a number of months.

It can be spreading between cows, and viral fragments have been present in pasteurised milk, in line with the US Department of Agriculture.

Transmission between mammals is a crimson flag for scientists monitoring viruses that might trigger the following pandemic.

A spokesperson for Defra stated it was intently monitoring the US state of affairs and collaborating with worldwide companions to know the origins and unfold of the outbreak.

"The risk level in the UK has not changed," they stated.

So far, 33 herds in eight states have been confirmed to be affected by the virus, however scientists imagine it has unfold way more extensively because the first experiences of a mysterious an infection in dairy cows in Texas in February.

A farm employee has additionally examined constructive, although they solely developed an eye fixed an infection.

Dr Mandy Cohen, director of the Centers for Disease Control and Prevention, stated: "The fact that it is in cattle now definitely raises our concern level.

"It's not a brand new pressure of the virus. This is thought to us. We've been learning it and been getting ready for avian flu for 20 years."

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Scientists are unclear on how the virus is spreading - or why solely dairy herds, not beef cattle, have been affected.

It may very well be that they've been fed contaminated poultry carcasses which were floor up of their feed.

Or that contaminated wild birds have gained entry to the huge and crowded sheds by which many US dairy herds are saved.

Movement of cattle, tools or folks is also serving to the virus to unfold.

The US Department of Agriculture has issued new guidelines in an try to comprise the virus.

Lactating cattle should now check unfavorable earlier than being moved to a brand new state.

Although H5N1 has undergone mutations to outlive in cattle cells, scientists say it's nonetheless a virus extra suited to birds.

The threat to folks continues to be thought-about to be low.