Alien In­va­sion: The Fun­gus That Came to Canada

The Washington Post Sunday - - Style - By Doug Struck

VIC­TO­RIA, B.C. — The mys­tery emerged slowly, its clues mad­den­ingly di­verse.

Sally Lester, an an­i­mal pathol­o­gist at a Bri­tish Columbia lab­o­ra­tory, slipped a slide un­der her mi­cro­scope — a tis­sue from a dog on Van­cou­ver Is­land. Her lens fo­cused on a tiny cell that looked like a boiled egg. It was late 1999. She had started see­ing a lot of those.

On the east­ern side of the is­land, sev­eral dead por­poises washed ashore early the next year. Sci­en­tist Craig Stephen, who runs a re­search cen­ter on the is­land, slit one open. He found its lungs seized by pneu­mo­nia and its other or­gans swollen by strange, flow­er­like tu­mors.

At work at the fam­ily truck­ing firm in Vic­to­ria, on the south­ern tip of the is­land, Es­ther Young, a lively 45-year-old mother, was feel­ing lousy in the fall of 2001. She had headaches and night sweats and was tired, her fam­ily said. The doc­tor told her she was pre-menopausal and it would pass.

All would be­come pieces of a med­i­cal mys tery cen­tered on a trop­i­cal dis­ease ap­par­ently

brought to North Amer­ica by a warm­ing cli­mate. An alien fun­gus took root on Van­cou­ver Is­land eight years ago and has since killed eight peo­ple and in­fected at least 163 oth­ers, as well as many an­i­mals.

Sim­i­lar cases have been found else­where in Bri­tish Columbia and in Wash­ing­ton state and Ore­gon. Sci­en­tists say the fun­gus may be thriv­ing be­cause of a string of un­usu­ally warm sum­mers here. They say it is a sign of things to come.

“As cli­mate change hap­pens, new eco­log­i­cal niches will be­come avail­able to or­gan­isms, and we will see this kind of thing hap­pen again,” said Karen Bartlett, a sci­en­tist at the Univer­sity of Bri­tish Columbia who played a cen­tral role in the search for the dis­ease’s cause.

Her in­ves­ti­ga­tion even­tu­ally would fo­cus on a fun­gus, a mem­ber of the yeast fam­ily, called Cryp­to­coc­cus gat­tii. The mi­cro­scopic fun­gus is nor­mally found in the bark of eu­ca­lyp­tus trees in Aus­tralia and other trop­i­cal zones.

Physi­cians in North Amer­ica are familiar with a rel­a­tive, Cryp­to­coc­cus ne­o­for­mans. In hu­mans, it shows up through pneu­mo­nia when im­mune sys­tems al­ready are weak, most typ­i­cally in AIDS pa­tients. In dogs and cats, it can form ab­scesses be­low the eyes. Lester, work­ing in her pathol­ogy lab in 1999, was used to see­ing tis­sue spec­i­mens from six to 10 pets a year with it.

But by 2000, vets on the is­land were send­ing her 10 pos­i­tive sam­ples a month. Lester knew Cryp­to­coc­cus causes a dis­ease that, like bird flu and West Nile virus, af­fects an­i­mals and hu­mans. She put in a call to the Bri­tish Columbia Cen­ter for Dis­ease Con­trol.

The call came at a busy time for Murray Fyfe. The head epi­demi­ol­o­gist at the pro­vin­cial CDC was then deal­ing with a bevy of other pub­lic health prob­lems: Peanuts from China had caused sal­mo­nella. Some lo­cal spinach was tainted. And there was a surge of men com­ing to hos­pi­tals with di­ar­rhea.

Fyfe con­sulted Pamela Kibsey, a mi­cro­bi­ol­o­gist at the Van­cou­ver Is­land Health Author­ity. Kibsey said she had no­ticed an in­crease in hu­man cases of Cryp­to­coc­cus. And there was some­thing strange about it. It was in­fect­ing healthy peo­ple, not just the sick.

Fyfe formed a group to be­gin comb­ing records of ve­teri­nar­i­ans and hos­pi­tals, trac­ing the first cases back to 1999. He asked Bartlett, at UBC, to join the group. They sent sam­ples of the Cryp­to­coc­cus re­cov­ered from dis­eased tis­sue for fur­ther anal­y­sis. The re­sults showed it wasn’t the familiar form of “crypto.”

“This was an Aus­tralian fun­gus,” Stephen said. “We said, ‘What’s a nice girl like you do­ing in a place like this?’ ”

More dis­turb­ing, the fun­gus ap­peared to be more vir­u­lent than in Aus­tralia. There, it in­fects about four peo­ple per mil­lion and is rarely fa­tal. On Van­cou­ver Is­land, the rate was 27 per mil­lion, and it was more of­ten killing peo­ple.

The sci­en­tists can only guess how, or when, the fun­gus ar­rived. It could have been brought on eu­ca­lyp­tus trees im­ported by nurs­eries from Aus­tralia. Or it may al­ways have been on the is­land, qui­etly cling­ing to life un­no­ticed un­til the warm sum­mers spurred it to pro­lif­er­ate.

“With global warm­ing, it may have fi­nally been able to emerge to a level [at which] it is in­fec­tious,” Fyfe said. Hu­mans and an­i­mals liv­ing in the area, hav­ing had no ex­po­sure, had de­vel­oped no im­mu­ni­ties to it. Some peo­ple re­acted to ex­po­sure by de­vel­op­ing the dis­ease.

Bartlett formed a team of stu­dents to try to find gat­tii in the wild. Armed with new de­tec­tion kits or­dered from Ja­pan, they tramped through back yards on Van­cou­ver Is­land, dig­ging up soil, tak­ing air sam­ples, swab­bing bark on trees. They went out with hour-long ques­tion­naires to talk to sur­vivors of the dis­ease and to own­ers of in­fected pets.

One com­mon site came up: Rathtrevor Beach Pro­vin­cial Park. It is an ex­panse of moss-cov­ered fir and hem­lock trees that reach for the sky, cheered by ravens and gulls, next to the Strait of Ge­or­gia. Pa­tient Es­ther Young had gone to the park to kayak. Sev­eral other pa­tients had been there.

Fyfe helped the stu­dents swab an old Douglas fir at the park. Two weeks later, Bartlett called him, ex­cited. The swabs had come back pos­i­tive, the first dis­cov­ery of Cryp­to­coc­cus gat­tii in the wild.

With the sum­mer of 2002 ap­proach­ing, Fyfe had a prob­lem. The park had a pop­u­lar camp­ground; fam­i­lies re­served a year ahead for tent spots. Fyfe knew most peo­ple could come into con­tact with gat­tii with no ill ef­fects. Those few who did be­come in­fected could be treated suc­cess­fully.

So he de­cided on a low-key in­for­ma­tion cam­paign. He posted pam­phlets in the park and sent out no­tices to va­ca­tion­ers who had made In­ter­net reser­va­tions. The re­ac­tion was prompt: The park got 750 can­cel­la­tions.

Word was also get­ting out through the news me­dia. Ken James heard it on TV. At 55, the for­mer mill­worker in the is­land town of Dun­can had been plagued by a tickle in his chest, a nag­ging cough, night sweats and an in­tense de­sire ev­ery day to take a nap. When he heard the re­port on “this weird fun­gal dis­ease,” he said, it ticked off the same symp­toms.

His doc­tor was skep­ti­cal, but a chest Xray showed nod­ules in his lung — ei­ther can­cer or the fun­gus. To James’s re­lief, it was gat­tii, and af­ter a year of oral med­i­ca­tion, he is cured.

“Did I walk past a tree when the fun­gus was ex­plod­ing? Who knows,” he said. “If I hadn’t seen that news re­port, things could have been very dif­fer­ent for me.”

By the start of 2003, Bartlett’s stu­dents had found the fun­gus in other spots. They even­tu­ally con­cluded that it had in­fested a sev­eral-hun­dred-mile range on east­ern Van­cou­ver Is­land. Health au­thor­i­ties agreed with busi­ness lead­ers in the ad­ja­cent city of Parksville that it was no longer fair to tar­get the park alone, and warn­ing signs at the Rathtrevor Beach park came down in fa­vor of a wider in­for­ma­tion cam­paign.

Health au­thor­i­ties still are strug­gling to strike the right bal­ance with the pub­lic. “It’s se­ri­ous, but it’s still a very rare dis­ease. Much rarer than in­fluenza, for ex­am­ple,” said Eleni Gala­nis, epi­demi­ol­o­gist at the B.C. Cen­ter for Dis­ease Con­trol. “Peo­ple need to be aware of it, in or­der to treat it. But we don’t want peo­ple to stop go­ing out­side.”

If doc­tors catch the dis­ease early, oral doses of an­ti­fun­gal drugs will kill the cells. Un­de­tected, the fun­gus can get into the spinal fluid, caus­ing po­ten­tially fa­tal menin­gi­tis.

Young went home sick in Fe­bru­ary 2002. By that sum­mer, she could not walk, had lost her abil­ity to speak, had gone tem­po­rar­ily blind and was slowly starv­ing be­cause she could not keep food down. By the time doc­tors tested her, the fun­gus had reached her brain.

“My poor sis­ter couldn’t even tell any­one how she was feel­ing,” said Deb­o­rah Chow, 51, rem­i­nisc­ing with her fam­ily. Fi­nally, with Young’s pain clear and the end in­evitable, Chow held her sis­ter in the hospi­tal and whis­pered, “It’s okay to go. Dad will be okay. Your son will be okay.” She died 45 min­utes later.

New cases on Van­cou­ver Is­land have lev­eled off at about 25 a year. Eight peo­ple have died. Bartlett’s fo­cus now is to fig­ure out whether — and how — the fun­gus is mov­ing.

Five hu­man cases have been found on the Bri­tish Columbia main­land; two peo­ple have been sick­ened in Wash­ing­ton state; and Ore­gon has had two fa­tal­i­ties from a sim­i­lar but not iden­ti­cal strain of gat­tii. Health au­thor­i­ties in Wash­ing­ton and Ore­gon say the dis­ease is still too rare in their ar­eas to war­rant alarm, but they are watch­ing it. Bartlett said it is un­clear whether the fun­gus has been tracked else­where on the bot­tom of shoes or in wheel wells.

“One pos­si­bil­ity for what we are see­ing on the main­land is the first col­o­niza­tion, like we had on the is­land in 1999,” Bartlett said. An­other is that those traces will dis­ap­pear.

The in­fected por­poises — at least 25 of them now — sug­gest the fun­gus is car­ried by air over the wa­ter. Stephen Raverty, a pathol­o­gist at the pro­vin­cial vet­eri­nary cen­ter in Bri­tish Columbia, wor­ries that the fun­gus can at­tack other species.

Killer whales, whose num­bers have dropped sharply here, are ce­taceans like the stricken Dall’s por­poises. Raverty and oth­ers have been track­ing the killer whales in Puget Sound, us­ing glas­sine slides mounted on long poles to catch droplets from the whales’ ex­ha­la­tions, to see whether the an­i­mals have been in­fected.

So far, they haven’t found the fun­gus. But an­i­mals can act as a sen­tinel for hu­mans, the sci­en­tists say.

“Th­ese are the types of things we will see with cli­mate change,” Fyfe said. “As the weather in North Amer­ica gets warmer, we are more likely to be af­fected by th­ese pub­lic health threats.”


Karen Bartlett, left, a Univer­sity of Bri­tish Columbia pro­fes­sor, formed the team that tracked the fun­gus to Rathtrevor. Ken James, above, rec­og­nized the symp­toms de­scribed on TV: “Did I walk past a tree when the fun­gus was ex­plod­ing? Who knows. If I hadn’t seen that news re­port, things could have been very dif­fer­ent for me.”

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