By Deb Courson, Contact

May 6, 2010

BOISE, Idaho - The wolf reintroduction debate in Montana has a new thread - with tapeworms winding their way into the discussion. A recent study found some wolves tested in the region were infected with Echinococcus - a type of parasite found in wild and domestic dogs. The tapeworm survives via a 'predator-prey' cycle, and reintroduced wolves are being blamed for bringing the tapeworm with them.

Wildlife veterinarian Mark Johnson, founder of Global Wildlife Services, oversaw the health of the wolves before they were reintroduced. He says the wolves aren't to blame.

"We treated every wolf at least twice with an injection of praziquantel. Those wolves did not have Echinococcus when they came in."

Johnson says it's clear to him the wolves got the tapeworm from local deer and elk. Several proposals are being discussed as possible ways to battle the tapeworm. One plan is to further reduce wolf numbers. Johnson says the way the tapeworm spreads has nothing to with how many wolves, foxes or coyotes there are - so it would be ineffective.

"Reducing the number of wolves, or density of wolves, will not change the abundance of Echinococcus in any way, shape, or form, because the wolves are not getting it from each other."

Johnson wants the public to understand that tapeworms have been around much longer than wolves, and people who could be exposed need to take precautions just like they do to protect against other hazards, such hantavirus and tick-borne diseases.

Those raising the issue say they're concerned the tapeworm might infect livestock, although that's never been documented. There also are human health concerns because people can become infected if they ingest eggs present in wolf, fox or coyote feces. Johnson notes that human cases are rare since egg-laden feces must be ingested to become infected.

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