Using prevalence data from the programme for the prevention of mother-to-child-transmission for HIV-1 surveillance in North Uganda

Objectives: To validate the use of data from a programme for the prevention of mother-to-child transmission (PMTCT) in estimating HIV-1 prevalence in North Uganda. Methods: The study was conducted at St. Mary's Hospital Lacor. We compared the estimated prevalence for 3580 attendees at the antenatal clinic who were selected for anonymous surveillance to that for 6785 pregnant women who agreed to undergo voluntary counselling and testing (VCT) for enrolment in the PMTCT programme. Log-binomial regression models were used to identify the factors associated with both VCT uptake and HIV-1 infection, which could bias the prevalence estimates based on PMTCT data. Results: In 2001-2003, the age-standardized prevalence was similar (11.1 % in the anonymous surveillance group and 10.9 % in the VCT group). The estimates were also similar when compared for each year tested. Analogously, no important differences were observed in age-specific prevalence. Of the factors associated with HIV-1 infection, only time of residence at current address [prevalence proportion ratio (PPR) = 1.05; 95 % confidence interval (0), 1.00-1. 10], marital status (PPR = 1.05; 95 % Cl, 1.01-1.10) and partner's occupation (PPR = 1.05; 95 % Cl, 1.01 -1.10) were associated with VCT uptake, yet the associations were weak. Conclusions: The prevalence estimated based on the VCT data collected as part of the PMTCT programme could be used for HIV-1 surveillance in North Uganda. At the national level, however, it needs to be evaluated whether PMTCT data could replace, or instead be combined with, the data from sentinel surveillance. (c) 2005 Lippincott Williams & Wilkins.