title: A decade of experience: Cryptococcus gattii in British Columbia.
abstract: It has been over a decade since Cryptococcus gattii was first recognized as the causative organism of an outbreak of cryptococcosis on Vancouver Island, British Columbia. A number of novel observations have been associated with the study of this emergent pathogen. A novel genotype of C. gattii, VGIIa was described as the major genotype associated with clinical disease. Minor genotypes, VGIIb and VGI, are also responsible for disease in British Columbians, in both human and animal populations. The clinical major genotype VGIIa and minor genotype VGIIb are identical to C. gattii isolated from the environment of Vancouver Island. There is more heterogeneity in VGI, and a clear association with the environment is not apparent. Between 1999 and 2010, there have been 281 cases of C. gattii cryptococcosis. Risk factors for infection are reported to be age greater than 50 years, history of smoking, corticosteroid use, HIV infection, and history of cancer or chronic lung disease. The major C. gattii genotype VGIIa is as virulent in mice as the model Cryptococcus, H99 C. neoformans, although the outbreak strain produces a less protective inflammatory response in C57BL/6 mice. The minor genotype VGIIb is significantly less virulent in mouse models. Cryptococcus gattii is found associated with native trees and soil on Vancouver Island. Transiently positive isolations have been made from air and water. An ecological niche for this organism is associated within a limited biogeoclimatic zone characterized by daily average winter temperatures above freezing.
authors.affiliation: School of Population and Public Health, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada. Kbartlet@interchange.ubc.ca
authors.forename: Karen H
authors.initials: KH
authors.lastname: Bartlett
authors.forename: Po-Yan
authors.initials: PY
authors.lastname: Cheng
authors.forename: Colleen
authors.initials: C
authors.lastname: Duncan
authors.forename: Eleni
authors.initials: E
authors.lastname: Galanis
authors.forename: Linda
authors.initials: L
authors.lastname: Hoang
authors.forename: Sarah
authors.initials: S
authors.lastname: Kidd
authors.forename: Min-Kuang
authors.initials: MK
authors.lastname: Lee
authors.forename: Sally
authors.initials: S
authors.lastname: Lester
authors.forename: Laura
authors.initials: L
authors.lastname: MacDougall
authors.forename: Sunny
authors.initials: S
authors.lastname: Mak
authors.forename: Muhammad
authors.initials: M
authors.lastname: Morshed
authors.forename: Marsha
authors.initials: M
authors.lastname: Taylor
authors.forename: James
authors.initials: J
authors.lastname: Kronstad
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001955:British Columbia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003453:Cryptococcosis / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology*; D056285:Cryptococcus gattii / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D004195:Disease Models, Animal; D004196:Disease Outbreaks; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D017720:Molecular Epidemiology; D012307:Risk Factors; D055815:Young Adult