Faculty of Agricultural, Life and Environmental Sci - Ag, Food & Nutri Sci Dept
Major Responsibilities and Research Interests:
I curated the University of Alberta Microfungus Collection and Herbarium (UAMH) from 1969 to 2013, negotiated its transfer to the Dalla Lana School of Public Health, University of Toronto, in 2015 and continue to provide ad hoc assistance to the Collection now renamed as UAMH Centre for Global Microfungal Biodiversity. See links to UAMH activities.
My research in fungal systematics is concerned with fungi that cause human and animal disease, produce toxins or metabolites of medicinal importance and occupy vertebrate-associated habitats. See current research areas and featured publications and Google scholar citations.
Fungi causing cutaneous disease in reptiles. In recent research, we have described new genera Nannizziopsis, Paranannizziopsis and Ophidiomyces and species of pathogenic fungi that cause cutaneous and invasive diseases in captive and free-ranging reptiles. Nannizziopsis guarroi is the cause of skin infections in captive bearded dragons known as yellow fungus disease that impacts the commercial bearded dragon pet trade. Infections caused by Paranannizziopsis species are frequently fatal in aquatic snakes in zoological environments and they also pose a threat to captive tuataras. These reptiles of ancient lineage are being closely monitored in New Zealand and elsewhere (e.g. London Zoo) to ensure their health and conservation. Ophidiomyces ophidiicola (formerly ophiodiicola) is the cause of snake fungal disease (SFD) in captive and free-ranging snakes and is an emergent global threat to populations of endangered wild snakes. The US National Wildlife Health Center now recognizes that, in laboratory and molecular evaluations, O. ophiodiicola is consistently associated with free ranging snakes with fungal dermatitis. Similarly, the Canadian Wildlife Health Cooperative (CWHC) identifies SFD is an emerging disease caused by O. ophiodiicola affecting wild snakes in eastern North America. In 2015, I confirmed for CWHC the first case in a sick snake in eastern Canada.
Systematics of dimorphic pathogens (Ajellomycetaceae). The study of Emmonsia species began in Alberta in the late 1940’s when fungal isolates were obtained from lungs of rodents. Many isolates from animals and human clinical sources were subsequently deposited in the UAMH Centre for Global Microfungal Diversity (see link). The two originally-described species, E. parva and E. crescens, do not cause disseminated disease, but rather a granulomatous lung disease in animals (and occasionally in humans) caused by inhalation of spores that inflate to form large spherules. Emmonsia species are closely related to the dimorphic fungi Blastomyces and Histoplasma species and together belong to a distinct lineage of the ascomycetes, the Ajellomycetaceae. Recent reports have identified Emmonsia-like fungi associated with many cases of mycoses among HIV+ individuals in South Africa and with infections in animals and humans in western North America. I am working with a consortium of scientists and clinicians to investigate the systematics of these unclassified isolates.