Epidemiology ofCryptococcus gattii, British Columbia, Canada, 1999–2007

Abstract

Incidence is high, but the predominant strain does not seem to cause greater illness or death than do other strains.

Criptococosis en Colombia: resultados de la encuesta nacional, 2006-2010

“…In regions like the Northern Territory in Australia, it has been reported that the mean annual incidence per million population was 6.6 and in New Zealand, of 2.2 (30), similar to the incidence reported in Colombia. The low incidence observed in HIV patients is consistent with reports describing the changing epidemiology of opportunistic infections in persons with AIDS (31). The fact that in Colombia the overall incidence of cryptococcosis among HIV patients has not changed significantly since 1997 may well be due to modifications in the management of HIV infection itself rather than to changes in environmental exposure to the fungus or to an increase in the virulence of the pathogen (16).…”

Cryptococcus gattii Infections

“…Similar observations were reported in PNG and were attributed to an increased exposure of males to environmental sources of C. gattii (209). On Vancouver Island, however, only 55% of the outbreak cases affected males, and in the Pacific Northwest, 54% affected males (132,198), suggesting that exposure is the predominant factor under these circumstances. Interestingly, 85% (21 of 25) of sporadic cases in the United States affected men (251).…”

“…VGII infections also occur but are, to date, geographically restricted to the Arnhemland region of the Northern Territory and the southwest of Western Australia (113,117). In contrast, clonal VGII subtypes (referred to as outbreak strains) of C. gattii caused case clusters in British Columbia (subtypes VGIIa and VGIIb) and in the Pacific Northwest (subtypes VGIIa, VGIIb, and VGIIc) (38,132,198,251); subtype VGIIc is a novel subtype not found outside the United States (68). Theories on how these VGII subtypes may have arisen in North America are discussed above (see Epidemiology, Origin, and Evolution, above).…”

“…It also poses a concern for veterinarians, and some animal infections, in particular those in feline and canine companion animals and Australian native koalas, represent sentinels for human exposure (37,176,188,190). Shifts in the appreciation of the clinical epidemiology of C. gattii in the past decade include the recognition that it affects immunocompromised (including those with HIV/AIDS) as well as immunocompetent (130)(131)(132)(133) hosts, the identification of multiple C. gattii molecular types (see Epidemiology, Origin, and Evolution, above) and their clinical implications, and the broadening of its geographic range beyond the tropical-subtropical locales of Northern Australia, Papua New Guinea (PNG), Southeast Asia, Africa, South America, and California (71) to the temperate regions of these and other countries (38,69,86,91,130,132,(196)(197)(198). This review focuses on these changes and their possible associations with disease patterns in humans.…”

“…However, following the North American outbreaks and, more recently, outbreaks in Australia, new risk groups have been recognized. These groups include patients with underlying HIV infection, cancer, solid organ transplantation, and other immunodeficiencies (96,98,130,132,198,230) (Table 4). In an Australian study of 86 patients, HIV was rare (1 of 79 patients tested for antibodies to HIV), but 7% of patients had underlying idiopathic CD4 lymphopenia, 3% had previously received kidney transplants, 8.1% had a malignancy, and 14% had received corticosteroids or immunosuppressive drugs (130).…”