It sounds like a villain from a science fiction film.
Cryptococcus gattii — an airborne fungus that appeared on Vancouver Island in the late 1990s — is real, and it’s gathering strength as it spreads to the south.
Though rare, the spore-forming fungus is potentially deadly to humans and animals.
It has mutated into a more lethal strain since it moved into Oregon, according to research published April 22 in the journal Public Library of Science Pathogens.
So far, C. gattii — which has been reported in cases in Whatcom, King and San Juan counties — has made no inroads on the North Olympic Peninsula.
“We’ve evaluated some people and animals but have yet to confirm a definite human or animal case,” said Dr. Tom Locke, public health officer for Clallam and Jefferson counties.
“It’s probably just a matter of time though. . . . This is one we expect to be watching for a long time.”
Cryptococcus gattii can cause symptoms in people and animals — including shortness of breath, chest pain, long-lasting coughs, fever and headaches — even weeks after exposure.
Like pneumonia
Most cases are like a pneumonia that slowly gets worse and worse.
Spores are inhaled and colonize the lungs before they spread throughout the body.
Treatment involves six to eight weeks of intravenous antifungal medications followed by months of pills.
“Overall, I don’t think it is a large threat at this time,” molecular biologist Edmond J. Byrnes III of Duke University Medical Center, the lead author of the report, told the Los Angeles Times.
“But the fact that it is continuing to spread geographically and the number of cases is rising makes it a concern.”
C. gattii is not transmitted from person to person or carried by insects or animals. Rather, the fungus forms spores that are blown in the wind or moved by soil disturbances of the soil.
Its primary habitat is trees, primarily Douglas fir and western hemlock.
People who stir up the soil — landscapers, loggers, outdoor recreationalists — are the most likely to encounter the fungus.
“Even then, the risk of human exposure is fairly low,” Locke said.
More lethal strain
Still, health officials are concerned because the strain of fungus that moved into the U.S. in 2004 has mutated to become more lethal than the original strain that invaded British Columbia in 1999.
Five of the 21 people who contracted the fungus in the U.S. have died, compared with 8.7 percent of the 218 infected people in Canada.
“The cases in Washington — and there’s only been eight or nine of them — are strongly linked to the British Columbia strain,” Locke said,
The Washington cases have been confined to three counties. Three cases have been reported in California.
Besides the wind, humans can spread C. gattii on shoes and even car tires.
“It’s something capable moving through the environment,” Locke said.
“We’ve been following this for the better part of the last decade when it first appeared on Vancouver Island and the British Columbia mainland,” Locke said.
Climate zone similar
“It has become established there in a climate zone that is actually very similar to the North Olympic Peninsula, especially the Sequim and Port Townsend area, which tends to be drier and warmer,” Locke added.
“It’s basically a tropical fungus which has become established in the Northwest and appears to be spreading.
“Fortunately it’s very rare — human cases of it — but it’s in this category of emerging infectious diseases that we watch very carefully.”
The fact that human cases are so rare could simply mean that mild cases are going unrecognized, Locke said.
Locke has talked about the fungus at county Board of Health meetings. Public health officials are trying to inform physicians so they can diagnose symptoms.
“Another form of Cryptococcus has been around a long time,” Locke said, referring to Cryptococcus neoformans, which kills 600,000 annually in tropical regions.
People living with AIDS, organ transplants or anyone suffering from immune deficiencies are most susceptible to neoformans.
“What’s different about gattii is that it can infect anyone,” Locke said.
“What’s new is it seems to have moved to the Pacific Northwest. That’s the mystery — how exactly that happened.”
Two years ago, Peninsula College tried to get a grant to study Cryptococcus gattii in its natural environment. Locke said the research would have been educational for students and valuable to public health officials.
“Unfortunately we were not able to get the grant,” he said.
Public health officials have been doing active surveillance of C. gattii for years.
“This has been on our radar screen for some time,” Locke said.
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Reporter Rob Ollikainen can be reached at 360-417-3537 or at rob.ollikainen@peninsuladailynews.com.
