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Multi-species outbreak of C. neoformans var. gattii on Vancouver Island. Colleen Duncan Western College of Veterinary Medicine, Centre for Coastal Health. Not reportable Multiple species Isolated cases Outbreaks rarely reported Not contagious Clinical signs
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Multi-species outbreak of C. neoformans var. gattii on Vancouver Island Colleen Duncan Western College of Veterinary Medicine, Centre for Coastal Health
Not reportable Multiple species Isolated cases Outbreaks rarely reported Not contagious Clinical signs Vary with organ involvement Acute to chronic disease Immunosuppression C. neoformans var. neoformans in Canada C. neoformans var. gattii in tropics and sub tropics ‘Traditional’ Presentation
Vancouver Island 2000-2003 • 1st report of an outbreak involving • Multiple species • Dogs and cats • 1stgattii in Canada • In humans? • Animals? • 1st report of Cryptococcus in wild cetaceans • 1st airborne CNvG • Over time • Organism size
History of Outbreak • Veterinary community • CVL: Aug 2001, 12 cases • Public health authority • Similar situation in people • ‘Case hunting’ • Local vets, laboratories, publications/notices • Case definition • Lab confirmed cases only
Species & Presenting Complaint October 2003
Annual Case Distribution October 2003
Monthly Case Distribution 1999-2003 October 2003
Culture results C.n.gattii serogroup B Animals Humans Environment PCR results Same fingerprint The Organism 1 kb marker (Gibco-BRL) R634 R794 F2596 F2932 F3179 F3197 99MR10 1 kb marker (Gibco-BRL) F2863 F2866 F3016 1 kb marker (Gibco-BRL) E113 ENV123 ENV124 ENV125 ENV129 ENV130 ENV131 ENV133 ENV152 ENV153 1 kb marker (Gibco-BRL) WM148 VNI Standard WM626 VNII Standard WM628 VNIII Standard WM629 VNIV Standard 1 kb marker (Gibco-BRL) WM179 VGI Standard WM178 VGII Standard WM161 VGIII Standard WM779 VGIV Standard 1 kb marker (Gibco-BRL)
Risk factors: Preliminary case-control study No significant risks E. Vancouver Island No immunosuppression Clustering? 3 cases of multiple animals/household Survey data: Positive titers 5/356 (1.5%) CNvG in external nares 4/380 (1%) Positive culture & titer 3/356 (<1%) Further Investigation
Human Cryptococcosis • Incidence pre-1999: 1-2 per million • 76 cases since 1999 • 1999: 8.5 per million • 2000: 26 per million • 2001: 24 per million • 2002: 35 per million • Culture: C.n.var.gattii serogroup B • 60% men • Most frequently 50-80 years old • 5-7 month incubation?
Human Case Control • Sex matched, N=30 • Risk factors • History of travel to park A • Oral steroid use • Preexisting lung disease • Protective • Cutting/chopping wood • Pruning trees • Branch clean up
Environmental Testing • March 2002: First environmental isolation • Alder, fir • Vertical (tree/air) & horizontal (soil) distribution • Trees remain infected over time • >20 infected tree species
Environmental Testing • Airborne Cryptococcus • May 2002 • 12%: deep lung • Chipping/cutting • ↑small particle % • ↑ airborne crypto • Cryptococcus in Soil • ↑concentrations away from trees • ↑concentrations in soil mid island than at either extreme
What’s The Big Deal? • Epidemiologically • Unusual manifestation of known agent • Not the usual crypto for BC • Not in the usual people/animals • Increased rate and clustering • Media/Public • Use of animal data
Many Thanks • Veterinarians of Vancouver Island • Centre for Coastal Health (Stephen) • UBC (Bartlett) • Central Vet Lab (Lester) • WCVM (Campbell) • BC CDC (Fyfe, MacDougall, Mak) • Animal Health Centre (Raverty, Lewis) • VIHA (Kibsey)