Footnote

The estimates of national HIV prevalence (the percentage of adults living with HIV nationally) vary because data are collected from different sources, for example from prevalence among women attending antenatal clinics and from household surveys. These different sources tend to give different results. Estimates based on antenatal clinics tend to be higher than those based on household HIV surveys.

Source & © UNAIDS  Report on the global AIDS epidemic: Executive summary, (2006), p.7