Districts selected for the survey.

<p>District selection stratified by mean HIV seroprevalence in antenatal clinic (ANC) surveillance sites, 2003–2005. Districts shaded blue had mean 2003–2005 ANC HIV seroprevalence 0–0.5%, yellow districts had ANC HIV seroprevalence 0.51–1.0%, and red districts had ANC HIV seroprevalence >1.0%. The districts of Davangere, Guntur, Nasik, and Tiruvanamalai were selected in the previous years' survey, and were purposively selected again for trend analysis.