title: Ecological niche modeling of Cryptococcus gattii in British Columbia, Canada.
abstract: BACKGROUND
  Cryptococcus gattii emerged on Vancouver Island, British Columbia (BC), Canada, in 1999, causing human and animal illness. Environmental sampling for C.gattii in southwestern BC has isolated the fungal organism from native vegetation, soil, air, and water.
  
  
  OBJECTIVE
  Our aim was to help public health officials in BC delineate where C.gattii is currently established and forecast areas that could support C.gattii in the future. We also examined the utility of ecological niche modeling (ENM) based on human and animal C.gattii disease surveillance data.
  
  
  METHODS
  We performed ENM using the Genetic Algorithm for Rule-set Prediction (GARP) to predict the optimal and potential ecological niche areas of C.gattii in BC. Human and animal surveillance and environmental sampling data were used to build and test the models based on 15 predictor environmental data layers.
  
  
  RESULTS
  ENM provided very accurate predictions (> 98% accuracy, p-value < 0.001) for C.gattii in BC. The models identified optimal C.gattii ecological niche areas along the central and south eastern coast of Vancouver Island and within the Vancouver Lower Mainland. Elevation, biogeoclimatic zone, and January temperature were good predictors for identifying the ecological niche of C.gattii in BC.
  
  
  CONCLUSIONS
  The use of human and animal case data for ENM proved useful and effective in identifying the ecological niche of C.gattii in BC. These results are shared with public health to increase public and physician awareness of cryptococcal disease in regions at risk of environmental colonization of C.gattii.
authors.affiliation: Epidemiology Services, British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada. sunny.mak@bccdc.ca
authors.forename: Sunny
authors.initials: S
authors.lastname: Mak
authors.forename: Brian
authors.initials: B
authors.lastname: Klinkenberg
authors.forename: Karen
authors.initials: K
authors.lastname: Bartlett
authors.forename: Murray
authors.initials: M
authors.lastname: Fyfe
mesh_terms: D000818:Animals; D001955:British Columbia; D003453:Cryptococcosis / Q000635:transmission / Q000662:veterinary; D056285:Cryptococcus gattii / Q000254:growth & development / Q000302:isolation & purification* / Q000472:pathogenicity; D017753:Ecosystem; D004781:Environmental Exposure; D004782:Environmental Health; D004783:Environmental Microbiology; D004784:Environmental Monitoring; D006801:Humans; D008954:Models, Biological