Dangerous fungus thrives on West Coast of Canada
The Globe and Mail, Feb. 10, 2007
A tropical and potentially lethal fungus that has mysteriously made a home on Canada's temperate West Coast has prompted foreign medical experts to issue a worldwide alert to doctors and tourists.
The warning comes after a 51-year-old Danish visitor contracted the rare and life-threatening fungal infection on Vancouver Island. In the January issue of the Journal of Emerging Infectious Diseases, published monthly by the U.S. Centers for Disease Control and Prevention, doctors in Denmark who eventually found clumps of the fungus growing in the man's chest have cited the island as a potential health risk to travellers.
Cryptococcus gattii, a microscopic pathogen normally found in tropical or subtropical locales in Australia, Africa, India or South America was first identified on Vancouver Island in 2001. Many suspect that global warming has recently enabled the one-celled organism to thrive in the trees, soil, water and air along the island's east coast.
While chances of contracting C. gattii remain low, the airborne cells and spores can lodge deep in the lungs, leading to pneumonia. The fungus can also attack the central nervous system and result in meningitis. As of December, 2006, 165 people had been infected and eight have died.
Agnes Thomas of Campbell River, B.C., contracted Cryptococcus gattii infection in 2003. She was initially diagnosed with lung cancer because an x-ray showed 12 masses in her lungs. Doctors later discovered the masses were not tumors, but the infectious fungal spores.
Animals, household pets in particular, have been hardest hit. But the corpses of infected porpoises have also washed ashore, making this one of the world's few, true multispecies outbreaks.
Human cases have emerged on the B.C. mainland, Oregon and Washington state. Every year, upward of 25 new human infections are reported. We are now up to 33 cases per million. We surpass any other place in the world, said Dr. Pamela Kibsey, medical director of microbiology at the Vancouver Island Health Authority.
Still, Dr. Murray Fyfe, medical health officer for VIHA, said the Danish report should be put in perspective. You are more likely to die in a motor vehicle crash going to the park, he said.
Dave Petryk, president and CEO of Tourism Vancouver Island, said the Denmark alert should not dissuade travellers from visiting the island. He said the risk of infection is extremely low and that people travel to other destinations with far worse health risks.
The Danish man who prompted the alert was admitted to hospital with fever and chest pains radiating to his left shoulder. Over the next five days, as his fever spiked and he struggled to breathe, a lung biopsy revealed he was infected with C. gattii cells he inhaled during his trip to Canada.
Dr. Jens Lindberg and colleagues from Denmark's Herning Hospital describe it as the first known case of intercontinental transmission and recommend tourists and medical staff of health-care centres worldwide be alert for symptoms of cryptococcosis after travel to Vancouver Island.
Yet while world experts take note, there's evidence that awareness still lags in Canada and even on the island itself.
Infections, usually curable with antifungal drugs when caught early, have been misdiagnosed in local patients and visitors. A 13-year-old Ontario girl who had camped on the island two years ago and later developed a brain infection had no inkling she had been exposed to the fungus. Last summer, a 26-year-old Nanaimo man was diagnosed just a few hours before he died.
Dr. Kibsey said some health officials have been reluctant to publicize the potential risks for fear of hurting tourism on the island, which receives more than seven million visitors a year.
In the summer of 2002, for example, those investigating the outbreak had put up a number of signs warning of the potential risk of fungal disease in the popular Parksville area of the island's east coast. But they didn't last past the season. The signs, Dr. Kibsey recalled, had prompted a huge number of campers to cancel their reservations en masse.
They were taken down because the chamber of commerce put pressure on the medical health officer to remove them.
Dr. Fyfe of VIHA said the signs were removed because further environmental sampling showed the fungus could be found throughout the eastern strip of the island, making it unfair to target one area alone. He noted that no warning signs are posted at the borders of Ontario, where infections from another environmental fungus have increased dramatically in recent years.
C. gattii is not contagious and is only known to be contracted from the environment. Most people exposed never develop symptoms. But there is no known way to prevent environmental exposures or predict who will be susceptible to them.
You can get it walking in the woods, standing under a tree, playing in a park or standing in your living room, said Eleni Galanis, a physician epidemiologist at the B.C. Centre for Disease Control.
Symptoms, which generally take two to nine months to develop, include night sweats, fever and chronic respiratory problems. The elderly, those taking steroids and people with lung conditions seem to be at higher risk. But the cases so far have primarily affected healthy adults and, some suspect, led to misdiagnosis.
That was the story of Mike Merriman, the youngest fatality known to date. His infection developed slowly with a brief bout of headaches and night sweats last June.
He thought he had a bladder infection; doctors suspected a kidney stone. Mr. Merriman continued working despite the flu-like symptoms, but on July 12 his body basically crashed, his mother Barbara said.
It was his mother who, after reading information on the B.C. CDC website, asked that he be tested for C. gattii. That evening, just a few hours after tests confirmed her suspicions, her son died.
We now know you do not need to have a compromised immune system, Ms. Merriman said. Obviously it can attack young people Mike was only 26.