Bird flu has been confirmed in a number of dairy herds in the US.

The latest case in the state of Idaho brings to 12 the number of herds in the US which have tested positive for highly pathogenic avian influenza (HPAI).

The detection was confirmed by the US Department of Agriculture (USDA) after tests were carried out by the National Veterinary Services Laboratories.

Seven of the herds are located in Texas, two are in Kansas and one herd respectively in both Michigan and New Mexico has tested positive.

Confirmatory tests on presumptive positive results are being performed on samples from Kansas, New Mexico, Ohio and Texas.


Last month, the USDA confirmed that it was investigating an illness among dairy cows which caused decreased lactation, low appetite and other symptoms.

On Monday 25 March, the USDA confirmed bird flu in two dairy herds in Texas and two in Kansas which had cattle with symptoms.

The US Department of Agriculture has so far confirmed the detection of bird flu 12 dairy herds in the country.

It then confirmed the disease in a Michigan dairy herd that had recently received cows from Texas. Testing confirmed that the strain found in Michigan was very similar to the strain confirmed in Texas and Kansas.

The authorities in the US said the disease appears to have been introduced by wild birds.

The spread of symptoms among the Michigan herd also indicates that bird flu transmission between cattle cannot be ruled out.


There continues to be no concern that this circumstance poses a risk to consumer health or that it affects the safety of the commercial milk supply because products are pasteurised before entering the market, the USDA said.

"Dairies are required to send only milk from healthy animals into processing for human consumption; milk from impacted animals is being diverted from the commercial milk tank or destroyed so that it does not enter the human food supply," it added.