The flu has been found in cows for the first time, but most cattle seem to be showing only mild symptoms and recovering from the illness. Officials say the pasteurization process means milk remains safe.
Midwest farmers and others in the dairy industry say they are staying vigilant but are not overly alarmed as bird flu spreads to a growing number of dairy cattle herds. Highly pathogenic avian influenza virus has been found in eight states, according to the U.S. Department of Agriculture.
This strain of avian influenza already had been detected in the U.S. in wild animals and poultry flocks, but in the last few weeks, it was found in dairy cows for the first time. The outbreak was first discovered in a herd in Texas and has since spread to dairy farms in New Mexico, Kansas, South Dakota, Idaho, Michigan, Ohio and North Carolina.
In the Midwest, Kansas’ Department of Agriculture and the USDA found the flu in three commercial dairy operations in late March. In a statement, Kansas Animal Health Commissioner Justin Smith said that they are working with federal and state health officials to monitor the situation.
“We encourage all livestock owners to practice enhanced biosecurity measures, especially limiting those who are moving on and off the premises,” Smith said. “We also encourage livestock owners and veterinarians to report cattle illnesses quickly so we can minimize any further impact in the state.”
Bird flu is often deadly for chickens, but so far it seems to be much milder for cows. The USDA advises farmers to look for symptoms including decreased milk production and decreased food consumption. So far, experts say only about 10% of the cows in an infected herd have gotten sick and for the most part, the cows have recovered.
That’s reassuring for dairy farmers, said Sean Cornelius, a third-generation dairy farmer and nutritionist in northwest Missouri.
“Everybody is very aware of the situation,” Cornelius said. “Farm owners, farm managers are definitely keeping in touch with their veterinarians and with their other resources to understand how the situation is evolving and I’d say not really alarmed by it, but being very vigilant.”
The virus has spread to at least one person during the current outbreak. A Texas commercial dairy worker developed conjunctivitis, or pink eye, and later tested positive for the virus. The worker was not hospitalized and there does not seem to be person to person transmission, according to the Centers for Disease Control.
“This particular virus doesn’t seem to be that pathogenic to people,” said Phillip Jardon, extension dairy veterinarian at Iowa State University.
To protect themselves, he said workers should wear personal protective equipment like goggles and a mask.
Experts think the dairy cows likely caught bird flu from infected wild migratory birds. On the Texas farms with some of the first detected cases, the USDA said there were dead infected pigeons, blackbirds and grackles.
To keep herds safe, veterinary experts recommend farmers delay plans to purchase new cows. If they are introducing cows to their herd, they should isolate the new cows they buy to make sure they are not sick.
“The fact that the cows in the herds that get it have a fairly low morbidity rate, not that many cows actually show the clinical signs and those that do eventually recover, I think this will pass as an issue for us,” Jardon said. “But it’s a problem in the meantime. I don’t want to downplay that either.”
Oklahoma State Veterinarian Rod Hall said he’s keeping the state’s dairy producers updated as the situation evolves.
“It’s not causing any panic,” he said. “The dairies are aware of it. And they’re taking the necessary precautions we believe, to keep from getting it.”
Milk is still safe to drink according to the USDA, because it is pasteurized — meaning it is heated to a high temperature for a set amount of time to kill off any potentially harmful microorganisms.
“Pasteurization has continuously proven to inactivate bacteria and viruses, like influenza, in milk,” the USDA said in an informational guide.
On top of pasteurization, dairy farms with symptomatic cows are disposing of milk. Cornelius said he hopes people understand that milk safety is top of mind for dairy farmers like him.
“I feel very safe and secure with my granddaughter drinking the milk supply today, even with this outbreak, because we know that milk is safe,” Cornelius said.
Milk prices are unlikely to be affected, the USDA said, because the number of cases is still low and the outbreak is coming at a time of year when milk production is generally higher.
This story was produced in partnership with Harvest Public Media, a collaboration of public media newsrooms in the Midwest. It reports on food systems, agriculture and rural issues.
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