Profiling of HIV clinic patients to determine the prevalence and characteristics of recent infections.

Patients newly attending the government HIV clinic in Hong Kong were studied for the prevalence and characteristics of recent HIV infection, which was defined as having a negative HIV antibody test and/or seroconversion illness within one year of a first positive antibody result. Fifty-nine (12.0%) of 492 HIV-positive patients first seen from 2001 to 2004 were determined to be recently infected. This likely represented the lower bound of the real situation. Compared with non-recent infections on univariate analysis, recent cases were more likely to be men who have sex with men (OR 2.23; 95%CI, 1.23-4.05), never married (OR 1.96; 95%CI, 1.03-3.89), had tertiary or above education (OR 3.93; 95%CI, 1.65-10.09) and with a baseline CD4>=500 cells/ul (OR 3.65; 95%CI, 1.87-6.93). Upon multivariate analysis, tertiary or above education (adjusted OR 4.23; 95%CI, 1.76-10.16) and CD4>=500 cells/ul at diagnosis (adjusted OR 3.58; 95%CI, 1.88-6.84) remained independent variables. HIV clinics are feasible settings for collecting epidemiological information of on-going infection. Differences in the profile between recent and non-recent cases may shed light on targeting efforts to prevent new HIV infections.