HPAI in Dairy Cows Hits Two More States

OMAHA (DTN) -- Confirmed cases of highly pathogenic avian influenza (HPAI) at North Carolina and South Dakota dairy farms now bring the total to eight states and 24 farms where a dairy herd has contracted H5N1 avian influenza.

State officials in at least four states -- North Carolina, Michigan, Idaho and Ohio -- have also said the infections in their states link back to their farms recently bringing in cows from Texas dairy herds.

Steve Troxler, North Carolina's agriculture commissioner, issued a statement that the National Veterinary Services Laboratory (NVSL) had detected HPAI in a North Carolina herd.

"This is an evolving situation, and we are waiting for more diagnostics from NVSL and will work collaboratively with our federal partners and dairy farmers in North Carolina," Troxler said. "We have spent years developing methods to handle HPAI in poultry, but this is new and we are working with our state and federal partners to develop protocols to handle this situation. It is important to note the FDA has no concern about the safety or availability of pasteurized milk products nationwide."

South Dakota officials stated the NVSL had detected HPAI in a dairy herd in that state as well.

"South Dakota Dairy Producers encourages all dairy producers to closely monitor their herd and contact their herd veterinarian immediately if cattle appear symptomatic," said Marv Post, Chairman of South Dakota Dairy Producers. "USDA continues to emphasize that pasteurization kills the virus and that milk and dairy products are safe to consume."

SOME STATES SAY LINKED TO TEXAS

Following a question from DTN, a spokeswoman for the North Carolina Department of Agriculture & Consumer Services stated the infected herd is linked back to a Texas dairy herd that also was infected with H5N1. State officials in Idaho, Michigan and Ohio also noted infected herds in their states had recently received dairy cattle from Texas dairy farms.

A spokesman for the New Mexico Department of Agriculture told DTN, "Our infections did not come from sick cattle being shipped in from Texas."

The virus was first detected in the Texas Panhandle. The impacted herds in New Mexico are located fairly close to the Texas-New Mexico state line, said Shelton Dodson, director of public affairs for the New Mexico Department of Agriculture.

Kansas has reported infected herds, but officials have not confirmed how its cattle became infected.

Texas officials initially reported the cows showing symptoms "were primarily older dairy cows," but North Carolina officials stated the cows that tested positive there were younger cows.

Beth Thompson, South Dakota's chief veterinarian, said in an email to DTN that the South Dakota Animal Industry Board is working with the affected dairy as part of its investigation to determine recent animal movements that may have occurred. "This work has just begun," she replied.

TEXAS SITUATION

In response to some questions from DTN, The Texas Animal Health Commission (TAHC) on Friday responded that 11 dairy herds in the Texas Panhandle have confirmed cases of HPAI. The total number of cattle infected "is still being characterized as the epidemiologic assessment unfolds."

The TAHC added, "Additionally, the TAHC cannot provide information related to results on individual dairies, to protect the privacy of the owners and their business."

Impacted herds have reported older cows in mid-lactation to be more severely impacted than younger cows and fresh cows or heifers, the TAHC stated. "To the best of our knowledge, the Texas cattle (1st lactation heifers) shipped to NC (North Carolina) did not show clinical signs consistent with affected cattle."

In terms of connecting the infections between states, the TAHC responded, "The TAHC, USDA, and other federal, state, university, and industry partners and subject matter experts are all actively working to collect and share epidemiology information, discuss diagnostic information updates, and work together to further characterize the full scope of the incident."

CONFIRMED HERDS BY STATE

USDA officials confirmed the infection of the North Carolina and South Dakota herds by updating a map. USDA's Animal and Plant Health Inspection Service website shows 24 herds nationally have been infected since the first case began. USDA is not listing the number of cattle confirmed as ill.

USDA also is not listing the number of cattle confirmed as ill.

The first cases of HPAI in cattle were confirmed March 25 by USDA, though Texas officials indicated cows at a pair of dairy farms were showing signs of illness earlier in the month.

Several other states also have banned or restricted the movement of dairy cattle. North Carolina and Tennessee suspended movement of cattle from affected herds in other states. Nebraska issued a restriction requiring a temporary permit for all breeding female dairy cattle from other states.

MILD SYMPTOMS OF ILLNESS

According to USDA, dairy cattle so far that have been infected with the virus have shown mild symptoms and recovered. South Dakota officials noted symptoms are mostly restricted to late-stage lactating cows and include a drop in milk production, loss of appetite, and changes in manure consistency. Producers are encouraged to enforce their biosecurity plans such as limiting visitors, separating new animals and sick animals, and cleaning pens, equipment, vehicles, clothing, footwear, and hands.

At least one person in Texas who worked on a dairy farm also was confirmed to have contracted H5N1 after showing signs of conjunctivitis.

NO IMPACT ON FOOD SUPPLY

Officials stress that HPAI infections in dairy herds do not impact the food supply. Dairies are required to ensure only milk from healthy animals enters the food supply chain. Additionally, the pasteurization process of heating milk to a high temperature ensures milk and dairy products can be safely consumed, as confirmed by the Centers for Disease Control (CDC). At this stage, there is no concern about the safety of the commercial milk supply or risk to consumer health. In line with long-standing policy, the CDC does not recommend consuming unpasteurized milk or raw milk. Pasteurization has continually proven to successfully inactivate bacteria and viruses, like influenza, in milk.

APHIS has more information about highly pathogenic avian influenza in dairy herds at https://www.aphis.usda.gov/….

Also see:

"Researchers Continue to Look for Transmission Source of Influenza in Dairy Cows," https://www.dtnpf.com/…

"Bovine Influenza A Virus Recommended as New Name for Recent Illness in Dairy Cows," https://www.dtnpf.com/…

Chris Clayton can be reached at Chris.Clayton@dtn.com

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