Taylor County Fair expects little impact with new H5N1 testing rules

Anyone who shows lactating dairy cattle at the fair will have to test their cow’s milk for H5N1 virus no more than seven days before the event.

“Right now it’s only affecting lactating dairy. The general visitor is not going to notice much. They will just see more hand sanitizer around,” said Kim Wilson, Taylor County Fair Board President. The Taylor County Fair typically has five to 10 lactating dairy cows. This year, there are nine signed up. “We are actually right on,” Wilson said.

While testing lactating dairy for H5N1 virus is new this year, animals are routinely checked for diseases at the fair. 'It’s a general procedure to have animals vet checked when they get here, which is the same as ever. The vet walks through every day and does a check that animals look healthy,” said Wilson.

The H5N1 testing requirement comes from the Wisconsin Department of Agriculture, Trade and Consumer Protection attempts to prevent the spread of H5N1 virus, better known as bird flu, to Wisconsin dairy cattle. While no herds have been infected in Wisconsin as of June 18, 100 dairy herds in 12 states have tested positive for H5N1. Levels of the virus tend to be particularly high in infected cow’s milk, which is why lactating dairy are the primary concern.

In March 2024, H5N1 virus was detected in dairy cattle herds in Texas and Kansas. The UW-Madison Alumni Association live-streamed an informational session about the virus on June 18. Panelists who spoke specialized in veterinary and dairy sciences. All facts listed are current to the June 18 presentation unless noted otherwise.

As many dairy farmers are aware, the virus unexpectedly jumped from birds into cows this spring. Dr. Darlene Konkle, the state veterinarian, stated the virus is milder in cows than in poultry, adding most cows recover from infection. Typical symptoms in cows include yellow, thick, and clotted milk. Additionally, infected cows will produce less milk and consume less food.

At this point, the risk posed by H5N1 to public health is low, according to Dr. Keith Poulsen, director of the WI Veterinary Diagnostic Laboratory. “The longer that the virus continues to spread, that risk goes up,” he said.

There have been four reported cases of the virus in humans in the US as of June 28. Three cases occurred in 2024, and one occurred in 2022. All three cases from 2024 were in people who worked in close proximity to infected cows. The four known individuals who contracted the virus in the US had relatively mild symptoms. All four recovered from H5N1.

This strain of H5N1 is different from an H5N1 virus people may remember from about 15 years ago. Thus far, this virus has shown less severe symptoms in humans than the past strain, according to Dr. Konkle.

To date, H5N1 has impacted poultry populations the most. Dr. Konkle noted that this has been the most expensive outbreak for poultry in US history. The virus has high morbidity in birds and transfers readily from bird to bird. Since 2022, over 800 flocks in the US have been infected with the virus. Current to June 27, one nonpoultry flock of eight birds in Taylor County was infected with H5N1 virus in November 2023.

Even as the virus has only spread from cows to humans three times, experts are concerned over the high amount of live H5N1 virus in unpasteurized (raw) milk of infected cows and the potential danger of infected milk to consumers.

As a general rule, milk sold at the store is pasteurized. The FDA conducted studies to determine if pasteurization inactivates H5N1 virus in infected milk. “Collectively, these studies provide strong assurances that the commercial milk supply is safe,” the June 28 update concludes. At this point, people generally should not be concerned about contracting the virus from any product made with pasteurized milk.

Milk that is transported across state lines is required by federal law to be pasteurized and is considered safe, but some states allow the sale of unpasteurized milk.

“Avoid consuming raw milk at any time, but especially now,” said Dr. John Lucey, Director of the Center for Dairy Research in Wisconsin. He noted that there is no nutritional benefit from drinking raw milk as compared to pasteurized milk.

People may encounter raw milk in specialty cheeses. Dr. Lucey recommended that people read the label on the cheese they buy to ensure that it is made with pasteurized milk. He added that most cheeses available in the supermarket are made with pasteurized milk. Cheeses made with raw milk tend to be artisan cheeses, which contain raw milk for unique flavor profiles.

The risk of consuming cheeses and other products made with raw milk was unknown as of a June 28 update from the FDA. “Based on the limited research and information available, we do not know at this time if the HPAI H5N1 virus can be transmitted to humans through consumption of raw milk and products made from raw milk from infected cows,” states the update.