Appearance of potentially lethal fungus in Canada

PULLMAN – Jack Rogers, WSU plant pathologist, says a potentially fatal-disease-causing fungus discovered recently in Oregon and Washington was previously found on the West Coast of Canada, where it has posed a threat to human and animal health for more than a decade.

“Cryptococcus gattii has been causing disease in Canada, especially the Vancouver region, since 1999,” says Rogers, a WSU Regents Professor and internationally recognized expert on mushrooms and fungi. “The fungus apparently lives on tree bark and other organic material and presents a hazard to humans and numerous animal species, especially perhaps those that live near a moist woodland or have hiked or camped in such.”

A paper announcing the discovery of the Pacific Northwest outbreak was published recently in “PLoS Pathogens,” where the authors noted that the disease is a significant “threat to agricultural and domestic animals… and thus the need for cooperation among health officials is critical.” The authors say that the type of C. Gattii found in Oregon is “hypervirulent” and that its range in the U.S. may expand further.

Speaking recently in Los Angeles, the paper’s lead author, Edmond J. Byrnes III, a molecular biologist at Duke University Medical Center, said he doesn’t consider the fungus a “large threat at this time” but expressed concern about its continued geographic spread and the increasing number of observed cases of fungal-caused disease.

Rogers says 21 cases of the fungal infection have been noted in humans in the United States, five of which resulted in death.

Because the incidence of disease from C. Gatti is so low, he said diagnosis can prove challenging to physicians, who often have little experience with fungal diseases of the lung.

“Antibacterial antibiotics are often prescribed and they are ineffective against fungi,” Rogers says. “A timely diagnosis and a course of one or more antifungal antibiotics is essential to preventing serious health consequences resulting from delayed treatment.”

For more information, contact Rogers at 509-335-3732; rogers@wsu.edu