Wasting Deer: Deer Saliva and Blood Can Carry Prions

Article excerpt

For the first time, researchers have shown that saliva alone can transmit a brain-destroying disease from one animal to another.

Three oral doses of saliva from a deer sick with chronic wasting disease passed the infection to other deer kept in isolation suites indoors, reports Edward Hoover of Colorado State University in Fort Collins. The finding gives substance to worries that the disease spreads through such deer social habits as touching noses and licking to groom each other.

The study also found that both an injection of blood from a sick animal and exposure to infected brain tissue transmitted the infection, Hoover and 16 colleagues report in the Oct. 6 Science.

Fourteen states and two Canadian provinces have reported chronic wasting disease, which strikes mule deer, white-tailed deer, Rocky Mountain elk, and occasionally moose. The disease belongs to the cluster of deadly brain ailments, such as mad cow disease, that are spread by misshapen prion proteins (SN: 11/30/02, p. 346). No case of human disease has been traced to game, but researchers haven't ruled out the possibility.

Biologists have known that animals can catch the disease simply by occupying an area where sick animals once lived. Contaminated land has vexed researchers, who don't want to risk introducing chronic wasting disease into diseasefree regions but don't want tests confounded by dirty fields.

For the new study, researchers at the University of Georgia in Athens supplied 14 white-tailed deer fawns. The state is free of chronic wasting disease. …