Canadian Anthrax Outbreak Worsens

An anthrax outbreak that began in early July has claimed 687 animals and caused 147 premises to be quarantined in Saskatchewan, Canada, as of Aug. 25, according to the Canadian Food Inspection Agency (CFIA). The outbreak is the largest on record to ever hit Saskatchewan. In Manitoba, Canada, CFIA officials confirmed anthrax cases on 18 premises, with 126 dead animals reported.

According to CFIA veterinarians, more than 250,000 animals have been privately vaccinated and 18,000 were vaccinated by the Canadian government. Most of the farms under 30-day quarantines raise cattle, but other premises housing horses, swine, bison, and white-tailed deer have also been quarantined. Anthrax is zoonotic disease--meaning it can be transmitted to humans by an infected animal or animal product--caused by the bacterium Bacillus anthracis or its spores. The spores are highly resistant to harsh weather conditions, meaning B. anthracis can survive in the soil for years.

Although anthrax is not as common in horses, those that ingest spores usually develop a very high fever and show signs of colic and/or diarrhea. They might also develop difficulty breathing (dyspnea) and can develop swelling on the underside of the neck and chest.

Anthrax outbreaks often occur following heavy rains--which push long-hidden spores into new, more accessible locations--or drought, which causes animals to graze closer to the contaminated soil.

"To the best of my knowledge, no new cases of anthrax have been confirmed by the lab since 28 July, 2006," said Randy Lindemann, DVM, North Dakota district veterinarian. "I have a stack of eight submissions to the Veterinary Diagnostic Laboratory, North Dakota State University, all of which are negative. This deal appears to have stopped short. We were having extreme heat with temps in the triple digit range at about that time. I don't know if that plays a role or not. I also don't know what to expect from here on."

About the Author

Chad Mendell

Chad Mendell is the former Managing Editor for .

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