Fort Smith (July 09/01) - An outbreak of anthrax infected and killed a bison herd in a remote part of Wood Buffalo National Park recently, forcing park officials to close a section of the sanctuary.

Laboratory tests came back last week confirming it was anthrax that killed a group of 19 bison near the Peace/Athabasca Delta in the park.

Client and heritage services manager, Mike Keizer, said that on Thursday, June 28, an RCMP flight over the Delta spotted a group of dead bison.

"We dispatched some of our wardens out to look at it and they identified eight dead bison at that point," Keizer said. "We spent the weekend doing monitoring flights, because we assume anthrax when we see that many dead animals."

Samples of the dead bison were flown to Edmonton for testing and returned last Wednesday, confirming the suspicion.

"We didn't find any dead animals elsewhere, but in the outbreak area where the eight were. We moved up to 14 as of Monday," he said adding that five more were found on Wednesday.

While park officials are hoping the outbreak is limited to this group, Keizer said the numbers could grow much higher.

"We had 130 with three outbreaks last year, so this is a low number right now," he said.

This outbreak was found to the east of last year's outbreak but has migrated back west towards the Sweetgrass Station.

There is no treatment available and even if there were, Keizer said there is no way they could inoculate the estimated 3,000 bison within the park's boundary.

Anthrax is an active bacteria in the bison, but once the animal dies the bacteria grows a husk or shell converting it into a spore that will lie dormant until ingested.

"It's a bacteria, that when out of the host body is a spore," he explained. "When it's in the ground they inhale it when they are grazing and they get a dose of anthrax and it's enough to kill them."

Unlike tuberculosis or bruscelosis, anthrax is not contagious. But because bison are social animals, if the herd migrates to an infected area, the whole herd could be wiped-out by anthrax.

The only way for humans to contact anthrax is through ingesting the infected animal and Keizer said there is little threat for park visitors.

"The outbreak is in a very, very remote part of the park, so it has very little effect from a visitor's perspective," he said. "It does not impact the majority of most people who visit Wood Buffalo National Park."