The U.S. is facing an avian flu outbreak—not in chickens, but in cows. The virus is spreading rapidly in California right now, and several states around Pennsylvania have seen cases in the past few months.

In turn, Pennsylvania’s Department of Agriculture is testing milk produced in the state for the disease and asking farmers to create plans that slow or stop the spread of disease.

“The Department of Agriculture is trying to be proactive in the event that there would be some cattle that would become sick in Pennsylvania,” David Smith said, the executive director for Pennsylvania’s Dairyman Association. "They can get ahead of the game and just control the spread of the disease.”

The state is covering the cost of the testing, which happens when the milk is at processing plants. In turn, they are asking dairy farmers to implement ‘bio security plans on their farms. These are day to day habits that can reduce the chance of any virus spreading.

“Organizing truck traffic and visitors to your farm… is 80-90% of it,” Tim Wood said, the state board director for District 5 of the Pennsylvania Farm Bureau. “[Also} What you do with a deceased animal, you know, composting and so on is is more strictly looked at.”

Since the first case in March, the U.S. has had 650 cows get infected across 15 states. Pasteurized milk from an infected cow is still safe for consumption. However,

“Milk production will decrease,” Smith said. “And while the cows will get at over the virus, it takes a while.”

The avian flu does not kill the cows. They become lethargic, which leads to lower milk production. However, the cow can in turn spread the disease to other animals nearby… including chickens.

“If we get it, there's so many farms that have a chicken barn on one side of the road and a cow barn on the other, especially down in the southern counties of the state,” Wood said. "And that's a recipe for bad things.”

The Avian flu is fatal to chickens, with oftentimes entire barns of birds getting wiped out.

Both dairy and poultry industries are huge economic drivers for Pennsylvania’s agriculture industry. There are around 465,000 dairy cows in the state and well over 2 million chickens.

“Chicken farmers were thinking that dairy farmers needed to get more vigilant,” Wood said.