Second Anthrax Case in South Dakota

On Aug. 16, the South Dakota state veterinary office confirmed the state's second case of anthrax this year. As a result of the outbreak, three beef cows that were part of a herd of 51 unvaccinated cows died in Lincoln County. An earlier outbreak in July struck another unvaccinated cattle herd in Hyde County.

Sam Holland, DVM, South Dakota state veterinarian, said, "Anthrax is a very serious disease because it can cause the rapid loss of a large number of animals in a very short time. Often animals are found dead with no illness detected."

Holland urged ranchers in the area to vaccinate their animals this year and to continue to do so for the next several years. He said nearly 1.5 million animals were vaccinated both last year and earlier this season.

Anthrax is zoonotic disease--meaning it can be transmitted to humans by an infected animal or animal product--caused by the bacteria Bacillus anthracis or its spores. The spores are highly resistant to harsh weather conditions, so the bacteria can survive in the soil for years. Anthrax naturally occurs in grazing animals (cattle, sheep, and goats), but virtually all mammals, including horses, can contract this disease.

Holland said weather conditions in the state probably contributed to the outbreak. "We've had good rains early on, and now we're somewhat dry in the middle part of the state," Holland said. Livestock ingest the spores when they forage close to the ground during drought, or when they eat feed grown on infected soil. Horses seem to be more resistant to anthrax than other livestock species, such as sheep or cattle.

Premises with confirmed cases are quarantined for a 30-day period, and all infected livestock must be buried or burned.

More than 500 cattle, bison, and deer died from anthrax in 18 South Dakota counties last year.

About the Author

Chad Mendell

Chad Mendell is the former Managing Editor for .

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