The Disease Ecology, Epidemiology, Clinical Manifestations, and Management of Emerging Cryptococcus gattii Complex Infections.

Cryptococcus neoformans, a soil-dwelling fungus found worldwide, can cause cryptococcosis, an opportunistic fungal infection of the lungs and central nervous system. One former member of the C neoformans complex, Cryptococcus gattii, has caused meningitis in immunosuppressed and immunocompetent persons in endemic regions in Africa and Asia. Between 1999 and 2004, C gattii caused outbreaks of human cryptococcosis in unexpected, nonendemic, nontropical regions on Vancouver Island, Canada, and throughout the US Pacific Northwest and California. C gattii was recognized as an emerging species with several genotypes and a unique environmental relationship with trees that are often encountered in the wilderness and in landscaped parks. Because C gattii infections have a high case-fatality rate, wilderness medicine clinicians should be aware of this emerging pathogen, its disease ecology and risk factors, its expanding geographic distribution in North America, and its ability to cause fatal disease in both immunosuppressed and immunocompetent persons.