Ehsan Jozaghi1,2, Kevin Yake3,4. 1. The BC Centre for Disease Control, 655 W 12th Ave., Vancouver, BC, V5Z 4R4, Canada. ejozaghi@yahoo.com. 2. School of Population and Public Health, Faculty of Medicine, University of British Columbia, 2206 East Mall, Vancouver, BC, V6T 1Z3, Canada. ejozaghi@yahoo.com. 3. Vancouver Area Network of Drug Users, 380 E Hastings St., Vancouver, BC, V6A 1P4, Canada. 4. The Western Aboriginal Harm Reduction Society, 380 E Hastings St., Vancouver, BC, V6A 1P4, Canada.