Laboratory diagnosis of the first cases of HIV-2 infection in Canada.

Until recently the geographic distribution of infection due to human immunodeficiency virus type 2 (HIV-2) had excluded North America. We report the first two cases of such infection in Canada. Both people came from endemic areas of western Africa and were asymptomatic. The results of a commercial enzyme immunoassay specific for HIV-1 antibody were positive in both cases, but those of the Western blot technique were indeterminate. The Western blot technique specific for HIV-2 antibody and the indirect fluorescent antibody test were used to verify the presence of HIV-2 antibody.