Two more cows die from anthrax in Colorado

Colorado's first anthrax outbreak in 31 years has expanded to three ranches in one week, with the deaths of two cows from anthrax exposures in northeast Colorado.

Last week on a Logan County ranch, 60 cows died with anthrax positively identified in one animal. It is likely they all died of anthrax, Businessweek reports.

The two most recent cow deaths were positively identified as stemming from anthrax. The cows came from two adjacent ranches, according to the Colorado Department of Agriculture.

All three ranches involved share fences, according to State Veterinarian Keith Roehr. He added that the new cases likely came from cows grazing in an area with soil containing anthrax spores, according to Businessweek.

No cows have left the ranches and none have entered the food supply and no cases of human infection have been reported, Roehr said, according to Businessweek. Additionally, neighboring herds have been vaccinated.

Anthrax requires quick treatment, Roehr said, adding that the disease can kill livestock and decimate herds within hours of infection.

Anthrax is caused by a bacterium that forms in spores and can lie dormant in soil for decades until ingested. Humans most commonly get anthrax when a cut or abrasion on the skin comes into direct contact with infected animals. The disease can be treated very effectively with antibiotics. Personnel on the affected ranches are being treated with antibiotics.

Agriculture officials and the Northeast Colorado Health Department are investigating the case. All the infected carcasses have been incinerated, a process that kills anthrax spores.

"At this point we really don't anticipate any health threat for the residents in northeast Colorado in regards to anthrax or from the smoke or plume from the incineration of the carcasses," Tony Cappello, the district public health administrator for the Northeast Colorado Health Department, said, Businessweek reports.

Roehr said that it is unclear why anthrax has suddenly surfaced for the first time in the area in more than 30 years. Though the area in which the ranches are located experienced floods followed by drought and the region has alkaline soil types, all characteristics favorable to anthrax spores.