Highly pathogenic avian influenza has been detected in single dairy cattle herds in both South Dakota and North Carolina.
The South Dakota Department of Agriculture and the Animal Industry Board confirmed the case on Wednesday, April 10. This is the first confirmed case of HPAI in a dairy farm in South Dakota. Other cases have been reported in Texas, Kansas, Michigan, Idaho, New Mexico and Ohio.
“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, in a statement to the press. “USDA continues to emphasize that pasteurization kills the virus and that milk and dairy products are safe to consume.”
The National Veterinary Services Laboratory has also detected HPAI in a dairy herd in North Carolina. Movement of cattle from affected herds in prior affected states to North Carolina has been suspended.
“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,” said Agriculture Commissioner Steve Troxler. “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.”
Research is still ongoing about how this virus spreads to dairy cattle, explained Beth Thompson, State Veterinarian for South Dakota.
“We know that the migration of birds is occurring right now,” she said. “It is possible that the virus is spreading via environmental contamination or other routes such as fomites.” Fomites refer to inanimate objects that can carry disease.
Symptoms of HPAI in dairy cattle are mostly restricted to late-stage lactating cows. Symptoms include a drop in milk production, loss of appetite and changes in manure consistency.
“Working with a veterinarian when seeing these signs, and/or calling the state veterinarian in your state is important to address herd health questions,” Thompson said.
Biosecturity plays a key role in stopping the spread of this virus. Producers are encouraged to enforce the biosecurity plans by limiting visitors and separating new animals and sick animals, as well as cleaning pens, equipment, vehicles, clothing, footwear and hands.
Avian influenza in dairy herds both increases the number of sick animals on the operation and decreases the milk production on that farm, Thompson explained. She said that as of right now, it does appear that the individual animals will recover.
Dairies are required to ensure only milk from healthy animals is entering the food supply chain. There is no concern about the safety of the commercial milk supply or risk to consumer health.
Pasteurization of milk has been proven to successfully inactivate bacteria and viruses, such as influenza, in milk. The Centers for Disease Control and Prevention does not recommend drinking unpasteurized, or “raw,” milk.
Avian influenza does impact other animal species, mainly wildlife.
Source: Reuters