According to CATIE.CA
There were an estimated 2,570 new HIV infections in 2014 (incidence).
An estimated 75,500 Canadians were living with HIV in 2014 (prevalence).
An estimated 0.2% of Canadians were living with HIV in 2014 (HIV prevalence rate).
I am not sure how many Gay Men there are in Vancouver but
Population of the lower mainland (2011) 2,590,921 assume 50% men so 1,295,460.5
Incidence of homosexuality in the general population in Canada is about 5.3% (Wikipedia)
That means there should be around 68,659 gay men.
If 1 in 5 (20%) of gay men living in the lower mainland had AIDS that would be : 13,731
I guess that sounds like a supportable number?