Utah Reports Avian Flu in Dairy Cows as USDA Announces Plan for Bulk Milk Sampling

By Lisa Schnirring

The Utah Department of Agriculture and Food (UDAF) yesterday announced that highly pathogenic avian flu has been confirmed at eight of the state’s commercial dairy farms, a development veterinary officials had been bracing for following a recent poultry outbreak that involved the cattle H5N1 genotype.

The eight facilities are located in Cache County, where bulk milk tank sampling had recently been ordered. The UDAF said the samples were initially tested at the Utah Veterinary Diagnostic Laboratory in Logan, and tests at the US Department of Agriculture (USDA) National Veterinary Services Laboratory have confirmed the findings.

State veterinarian Daniel Christensen, DVM, said mandatory surveillance and animal movement restrictions are key steps to prevent further spread of the virus. “At this time we don’t anticipate any major impacts on the food supply and the overall impacts to individual dairies are relatively minimal. This disease is not as harmful to dairy cattle as it is to poultry,” he said.

After confirming the virus in a poultry flock in Cache County earlier this month, the UDAF quickly announced mandatory weekly bulk milk tanks sampling for all of the county’s dairies.

In other developments, the USDA Animal and Plant Health Inspection Service today confirmed 9 more H5N1 outbreaks at California dairy farms, raising the state’s total to 202 and the national total to 404, which will rise to 412 once the Utah’s outbreaks are added to the list.

Feds to launch bulk milk testing

California and Colorado—two of the hardest hit states—had instituted mandatory bulk milk tank testing to get a better grip on the extent of spread in dairy cows.

Yesterday, APHIS announced a tiered strategy to collect milk samples to better assess where H5N1 is present proactively support effective biosecurity measures and to help state minimize the risk to farm workers. It noted that bulk milk testing helped stamp out brucellosis in US dairy herds and that Colorado’s use of the testing helped the state stem its surge over summer months.

APHIS said in the weeks ahead it will work with regions and states that are ready to expand bulk milk testing. The rollout of testing will begin at the regional level, with additional testing at the farm level, if needed, until all herds are free of the virus. “USDA will continue to work with state and private veterinarians on the final details of implementation, and will share guidance documents soon,” it said.

Washington reports 3 more infections in poultry cullers

The Washington State Department of Health yesterday reported three more avian flu infections in poultry cullers, raising the state’s total to nine. The cullers were part of a response to an outbreak at a large layer farm in Franklin County.

The Centers for Disease Control and Prevention (CDC) has confirmed all nine of Washington’s cases, which it said puts the national total for the year at 39. All but one involved farm worker exposure to sick poultry or cows.

Avian flu strikes more poultry in California

Elsewhere, APHIS has confirmed four more avian flu outbreak at California broiler farms, one in Tulare County and three in Kings County. Both counties are in the state’s Central Valley, the part of California hit hard by the H5N1 outbreaks in dairy cattle.

USDA also reported a new outbreak in backyard poultry in Tulare County.

It’s not clear if the outbreaks are due to the cattle genotype or to a wild bird H5N1 genotype. A few western states have reported upticks in poultry outbreak that has coincided with the seasonal migration of wild birds along the Pacific Flyway.

The California Department of Agriculture and Food said in an update yesterday that the source of virus is under investigation. It will conduct tests at other farms over the next several weeks to determine the extent of the spread.