Cryptococcus gattiiVGIIb-like Variant in White-Tailed Deer, Nova Scotia, Canada

In Vitro Antifungal Susceptibility of Environmental Isolates of <i>Cryptococcus</i> spp. from the West Region of Cameroon

“…neoformans and C. neoformans var. gattii in the west region of Cameroon confirm the geographical distribution of C. neoformans as described in several previous studies (15, 5, 4, 19). In fact, most of these previous studies showed that C. neoformans var.…”

Dating the Cryptococcus gattii Dispersal to the North American Pacific Northwest

“…There is no other current evidence of long-distance dispersal of VGIIb across the North American continent, nor is there evidence of transport of animals from the PNW to the region, as the infected deer was part of a local deer population. White-tailed deer are nonmigratory, providing further evidence of the presence of VGIIb in Nova Scotia, and this is suggestive of a unique introduction/dispersal event in the region ( 17 ). The province of Nova Scotia is a peninsula that is surrounded by four major bodies of water, and the city of Halifax, throughout its history, has been an active sea port, one of the major international points of entry for shipping into Atlantic, Canada.…”

“…The newly sequenced 2015/2016 isolates of VGIIa, VGIIb, and VGIIc all grouped within the PNW clades. Two 2015 autochthonous VGIIa isolates from Québec, Canada ( 16 ), that grouped together within the PNW clade, seemingly derived from an Oregon strain lineage, and one 2015 wildlife isolate from Nova Scotia ( 17 ) that grouped within the primary VGIIb PNW clade seemingly derived from a Washington lineage. The three PNW genotypes all continue to be clonal, with no evidence of recombination based on the pairwise homoplasy index (PHI) statistic.…”

“…The identification of VGIIa in a pet store bird (sample number B11566) and a separate, unrelated case in pet store worker (sample number B11569), both in Québec, are unexpected occurrences ( 29 ), and it is of interest to note that the bird reportedly originated from British Columbia and the infecting C. gattii strain clearly evolved from the PNW VGIIa population, suggesting a linkage to human transport of animals as the cause. Conversely, the appearance of a PNW-derived strain of VGIIb (sample number B11567) in a Nova Scotia yearling white-tailed deer ( Odocoileus virginianus ) ( 17 ) is less explainable. There is no other current evidence of long-distance dispersal of VGIIb across the North American continent, nor is there evidence of transport of animals from the PNW to the region, as the infected deer was part of a local deer population.…”

“…Given the commonality of just under 100 years for the PNW arrival of the VGIIa, -b, and -c subtypes and given their lack of known presence elsewhere on the North American continent (with three notable exceptions: a single Florida VGIIb isolate [ 28 ], the recently discovered Québec cluster of VGIIa [ 16 , 29 ], which seems to have derived from the PNW VGIIa population, and the single VGIIb isolate from a deer in Nova Scotia [ 17 ], likely derived from the PNW VGIIb population), it is logical to hypothesize that these C. gattii subtypes arrived in the PNW region shortly into the 20th century. It is possible that populations arrived elsewhere on the continent and failed to become established; a similar scenario was seen with the concurrent spread of Yersinia pestis by boats from Asia to multiple U.S. ports around the turn of the 20th century that only became enzootic through the ports in California ( 30 ).…”