Animal Health

Anthrax

Anthrax is a disease caused by the spore-forming bacteria Bacillus anthracis. Anthrax spores are naturally present in soil across the United States and the world, where ideal weather conditions and specific soil types create a favorable environment. In these areas, spores can survive indefinitely in the soil, and anthrax outbreaks are not uncommon.

Anthrax primarily affects domestic and wild herbivores. Affected livestock species include: cattle, sheep, goats, bison, horses. Wild herbivores, including elk, bison, pronghorn, deer, and occasionally moose may be affected. Carnivores, including dogs and cats, are rarely infected with anthrax. Anthrax is a reportable disease to the Wyoming Livestock Board and the Wyoming Department of Health.

Anthrax is a zoonotic disease. This means that anthrax infected animals can spread the disease to humans. Handling sick or dead animals, or ingesting undercooked meat from an animal that has been infected with anthrax can spread the disease to humans. Spread of anthrax from person-to-person is unlikely.

Exposure

Animals are exposed orally or through inhalation while grazing on pastures or landscapes where anthrax spores are present in the soil.

Clinical Signs

  • The most common sign of anthrax is sudden death.
  • After death, dark blood may ooze from the mouth, nose, and anus.
  • Prior to death, infected animals may have a fever, stagger, tremble, and have difficulty breathing. Animals often die within 24-72 hours.

Diagnosing Anthrax

  • Anthrax should be suspected in all cases of unexplained sudden death. A necropsy should not be performed until anthrax is ruled out. Opening the carcass can expose both humans and other livestock to anthrax.
  • A diagnosis of anthrax is made by testing the peripheral blood of infected animals and identifying DNA of the anthrax bacteria in the blood (PCR assay).
  • The blood sample should be collected by a veterinarian wearing appropriate personal protective equipment.

Prevention

Avoid contact with dead animals:
  • Call your veterinarian immediately if you have unexplained livestock deaths.
Use personal protective equipment:
  • Wear a mask, gloves, boots and coveralls when handling sick or dead animals.
Vaccination:
  • Vaccination of livestock in anthrax endemic areas is critical for prevention. The vaccination is available through your veterinarian. For optimum efficacy, the vaccine must be administered annually, before exposure to anthrax.
Carcass management:
  • If not managed properly, the remains of animals that die of anthrax will contaminate the soil with anthrax spores. This contamination is indefinite!
  • Do not move carcasses if at all possible. Movement increases soil contamination.
  • Optimal disposal of infected carcasses: cremation, then burial of cremated remains.
  • Alternatively, carcasses can be buried a minimum of 6 feet deep. Bury blood contaminated soil with the carcass.

Where is anthrax historically endemic in Wyoming?

Anthrax outbreaks have been documented in cattle in Carbon, Laramie, Niobrara, Goshen, Natrona, Lincoln, Sublette, Sheridan and Teton counties.

Who should I contact if I suspect anthrax in…

Livestock:
Contact your veterinarian immediately.
Anthrax is a reportable disease. Immediately report suspect or confirmed anthrax cases in livestock to the Wyoming Livestock Board

307-777-7515

Humans:
Contact your physician immediately and Wyoming Public Health

307-777-7656

Wildlife:
Contact Wyoming Game and Fish

307-777-4600

Official Forms

WLSB Anthrax Protocol