Should Texas Ranchers Worry About Anthrax?

A map of reported Anthrax cases in Texas, by county. Map by Michael Marks

Texas is cattle country: there are nearly 13 million cows wandering through Texas, according to the United States Department of Agriculture. That’s over 14 percent of the country’s total cattle population.

And our bovine friends have some company: there are also approximately 1.3 million goats, nearly one million horses, and 3.6 million deer.

So if just one grazing animal died of a lethal and highly transmittable disease, there would be cause for concern that large numbers of animals could be at risk.

That’s exactly what happened last Monday when the Texas Animal Health Commission confirmed that a cow had died of anthrax southwest of San Angelo.

Photo courtesy, Dr. Floron Faries, Texas A&M AgriLife Extension Service

An anthrax-infected deer carcass

Anthrax is found naturally in the soil, and “commonly affects domestic and wild animals around the world,” according to the Centers for Disease Control and Prevention. Animals contract anthrax by ingesting bacterial spores in the ground while grazing, so it’s most common among cattle, deer, goats, and horses. The disease is “invariably” fatal, according to Texas A&M Agrilife, and an animal will die a few days after contracting it.

Drought can make anthrax more common because its spores tend to rise to the surface when soil becomes dry and dusty. These patches of spores are called “hot spots.” They can spread by being blown by the wind or washed away by rain once they reach the surface.

Animals are most vulnerable to anthrax in the summer. Over the last decade, 25 of the 27 reported cases of anthrax in Texas occurred between June and September.

Anthrax is most common in a sparsely-populated agricultural region west of the Hill Country, in counties like Val Verde, Uvalde, and Sutton. Even so, Texas’ ranchers, farmers, and hunters aren’t panicking over the news.

It’s still a stretch to call anthrax “common,” says Josh Blanek, an Agrilife Extension Agent for Tom Green County. Tom Green is the county where the most recent reported case of anthrax occurred.

“The amount of livestock affected by [anthrax] in a year compared to the amount of livestock that are out there, it’s nothing to be concerned about,” he says.

One of the reasons that anthrax is so rare is that a vaccine is so cheap. A quick search shows that you can buy 50 doses of anthrax vaccine for about $50, shipping included. Blanek says it’s a worthwhile investment, given the current price of livestock. The A&M Agrilife service is encouraging ranchers to vaccinate their animals.

“A dollar a head is cheap insurance. When you lose a cow or lose a sheep, you can pay for a lot of vaccine with it,” he says.

Farmers, hunters, and ranchers don’t need to worry about keeping any for themselves, though.

Blanek and others say to be careful around carcasses or animals displaying strange behavior. But no human in Texas has ever died from contracting anthrax, according to records from the Texas Department of State Health Services. Still, A&M Agrilife is warning people to stay away from infected animals that are still alive, and use caution around carcasses. The signs to look for, from A&M Agrilife’s website:

“The carcass of an animal killed by anthrax usually shows little or no rigor mortis or the stiffness that occurs soon after death. Dark non-clotting blood usually oozes from the mouth, nose and anus and the body quickly bloats and decomposes rapidly.”

“Anthrax has been around since the buffalo roamed the plains,” says Blanek. “It’s here, it’s always been here, and it’s going to be here to stay because it is a soil bacteria. It’s not a big problem.”