Unlinked anonymous monitoring of HIV prevalence at sexually transmitted disease clinics

Abstract

Aim: To determine the prevalence of HIV infection among patients attending the four sexually transmitted disease (STD) clinics in two metropolitan areas of New Zealand.

Methods: The population studied comprised everyone who attended between August 1991 and August 1992 because of concern about a possible new episode of an STD and who had a blood specimen taken for hepatitis B (or syphilis) serology. The study involved unlinked anonymous testing of left-over blood specimens, following ethical guidelines that have been proposed internationally.

Results: Among 8478 specimens tested, 23 (2.7 per 1000) were found to be HIV positive. The seroprevalence rates per 1000 among women, heterosexual men, and homosexual or bisexual men were 1.1, 1.3, and 44, respectively. All but five of the infected people were either known to be HIV positive or had an identifiable test during their clinic attendance.

Conclusions: The seroprevalence rates are similar to those reported from STD clinics in England, and suggest that heterosexual transmission of HIV infection has not yet been extensive in New Zealand.