by David Minkow
Source: Monday Magazine
Original Article: Click Here
Originally Published: JUly 30, 2008
Fungus Among Us
By DAVID MINKOW
Is Cryptococcus gattii the Island’s deadly secret or just one more sickness we’re learning to live with?
A picnic at the beach was suddenly no picnic. My son and his cousins were poking around at the base of some Douglas firs at Rathtrevor Beach Provincial Park on a glorious April afternoon when I remembered.
A worst-case-scenario kind of guy, I had scoured the internet for anything rotten about Vancouver Island before deciding to move here last year. The worst I could find—other than how Victoria treats its sewage—was Cryptococcus gattii, a sometimes-lethal fungus first identified growing in Douglas firs . . . at a beach in Parksville with an odd name.
I knew that the fungus had spread well beyond Parksville—north to Campbell River, south to Victoria, west to Port Alberni as well as incursions into Washington, Oregon and B.C.’s Lower Mainland—but here were the trees, the ground-zero trees. Even though the spores released by the fungus are microscopic, I could swear I saw them drifting into my son’s four-year-old lungs.
Back home in the Cowichan Valley, I asked around about the disease; most people had never heard of it and those who had weren’t very concerned. Later that week, an obsessive evening of Googling didn’t reveal much new information, but I did read about a report bemoaning the paucity of news coverage about Cryptococcus gattii, especially when compared to West Nile Virus, which has yet to invade the province.
The next morning, the local paper reported that a 45-year-old woman in Cowichan Bay had died—the ninth fatality in B.C. since the first known case in 1999. The way the article mentioned that one person dies each year from the disease made it sound that we were safe for the rest of the year.
Well, I didn’t feel safe. I’m always telling my bug phobic mother she has to make peace with the insect world because her fears make her a magnet for bug bites. And now here I was freaked out over what was in my son’s next inhale.
I realized that I needed to come to peace with the idea of my children growing up gattii, so I decided to consider all the reasonable reasons that could dispel my fears.
The odds are in our favour
You’re much more likely to get hurt on the way to the beach than get infected by Cryptococcus gattii. I heard that from everyone I interviewed, including a recovered patient (nobody mentioned anything about air bags or daytime running lights).
This the largest-ever outbreak of Cryptococcus gattii and our particular strain appears to be more virulent than in the tropical and subtropical places it normally lives (notably Papua New Guinea, India, southeast Asia, Mexico, Brazil, Paraguay and parts of Africa). Still, since 1999, the B.C. Centre for Disease Control has recorded only 231 human cases (there have been at least several hundred animal cases, including porpoises, cats, dogs, ferrets and llamas, but it is not a reportable condition in animals).
“It is an extremely rare disease,” says BCCDC epidemiologist Eleni Galanis, who notes that while the overall infection rate is rising due to the fungus’ expanded range, the number of human cases on Vancouver Island has plateaued at about 15 a year.
The incubation period is quite variable—from several weeks to a year or longer—but most cryptococcus infections start off as chest infections. Common symptoms include night sweats, a prolonged cough, weight loss, fever and headaches. A chest x-ray will reveal a shadow on the lungs which can be mistaken for cancer, but a tissue sample will show that it’s Cryptococcus gattii. If properly diagnosed, it is treatable with antifungal drugs; if, however, the fungus gets into the bloodstream and moves into the brain, it can lead to meningitis and be fatal.
Murray Fyfe, medical health officer with the Vancouver Island Health Authority, says physicians here are well-aware of the disease; he and others worry about international visitors not knowing to tell their doctors back home where they’ve been and their doctors not knowing to ask.
Karen Bartlett, an epidemiologist at UBC’s school of environmental health, was instrumental in linking the deaths of 25 porpoises and on-shore infections of humans and other animals to Cryptococcus gattii. But when she went to the library to look up information, all the textbooks stated that this fungus only lives in tropical parts of the world.
“It was a medical mystery,” she recalls. “What the heck was going on?”
Seven years later, it’s still not clear how a tropical disease has taken up residence in every native tree—Douglas fir, maple, arbutus, Garry oak, alder, etc.—in a temperate zone. Did it emigrate from Australia where it infects eucalyptus trees, or has it always been here in lower concentrations, waiting for a perfect storm of warmer summers and soil disturbances (highway construction, clearcutting) in the 1990s?
The other critical missing piece of the puzzle is host susceptibility. The average age is over 50, but you can be young or old, male or female, urban or rural—or even housebound—and still get infected. In some cases, there are risk factors such as smoking and weakened compromised immune systems, but in most cases there isn’t a clue. According to Galanis from the BCCDC, “Why some people get it and others don’t, we really don’t know.”
Don’t fret over what you can’t do anything about
There’s no vaccine. There’s no way to selectively kill it. There’s no point in cutting down infected trees since the fungus can also survive in the air, soil and water. And there’s no way to tell if you’ve been exposed because the current anti-body test doesn’t differentiate between Cryptococcus gattii and its more-common and more-benign cousin Cryptococcus neoformans.
“We don’t have any preventive measures for cryptococcus. The only thing we do have is awareness,” says Fyfe, who posted warning pamphlets at Rathtrevor Beach in 2002—only to remove them after 750 camping reservations were cancelled and local business leaders complained that the park was being unfairly targeted for the wide-ranging fungus.
Bartlett and others suspect that global warming has given Cryptococcus gattii a competitive advantage. She found that the fungus—which contains melanin that protects it from sunlight—exists in higher concentrations in the air during dry summer weather, and that all the areas where it’s been located in the Pacific Northwest are in the increasingly hot and dry rain shadow of the Olympic Mountains.
At the same time, it appears that our bodies might be adapting to the fungus. There is a hypothesis that Vancouver Island residents are developing immunities to it.
“What we’ve found at this point is that the more you are out and about, the less likely you’re going to get the disease,” Bartlett says.
This may explain why visitors—such as a healthy 51-year-old Danish man who only visited for a week in 2006—get infected, while the vast majority of lifelong residents haven’t.
Help may be on the way
Research money has been hard to come by for B.C. cryptococcus researchers, mainly due to perceptions that it’s a local problem. As the fungus increases its presence in Oregon and Washington—where two people have died—it is hoped that more research dollars will follow. The BCCDC is already collaborating with public health officials in both states, as well as the CDC in Atlanta, to raise awareness.
All in all, talking to the experts has put me more at ease. I especially like the immunity theory—though we do get a lot of visitors and I’d hate for it to be their final vacation. Yet, living amidst an invisible killer that seemingly strikes at random is disconcerting.
Sure, I’ll learn to live with it, just as I did in San Francisco, with the threat of earthquakes, wildfires and drive-by shootings, and just as people do in other parts of California, where the fungus that causes Valley Fever—coccidioidomycosis—lives in dry soil waiting to be disturbed. But I’d like to see more public dialogue and more media coverage (and more research money) to raise awareness. It’s critical.
Ken James, 57, of Duncan told me how in 2001, he watched one of the first reports of Cryptococcus gattii on the evening news and recognized the symptoms. His doctor agreed to consider the possibility and James was soon diagnosed and treated in Victoria. “If I hadn’t seen it on TV that night, I don’t think that I would be alive today,” says James, who is fully recovered, except for perhaps a little less energy.
While I worry that the disease is a harbinger of things to come, it may also serve as a climate-change wake-up call.
Craig Stephen, founding director and president of the Centre for Coastal Health, has been involved since the early days of the disease, now endemic to Vancouver Island. “Cryptococcus reminds us that we live in the world around us and are intimately connected with other environmental organisms,” he says, adding, “It’s still better to take your dog for a walk than to stay inside . . . At the end of the day, I think it’s bad luck.”
My mother recently announced that during their next visit they wanted to stay at a resort they had read about in Parksville. I reluctantly informed my mom about the cryptococcus connection, but to my amazement she was unfazed. On her street in Michigan she sometimes sees dead crows, victims of West Nile Virus. She’ll take her chances with Cryptococcus gattii.
As, I guess, will I.
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