Prevalence, incidence, and mother-to-child transmission of HIV-1 in rural South Africa.

Simple, robust approaches are needed to monitor prevalence, incidence, and mother-to-child transmission of HIV-1 in rural Africa. We have designed a method that uses antibody and viral RNA testing of dried blood spots obtained from mother-infant pairs attending routine immunisation clinics. In our study, prevalence and incidence of HIV-1 was highest in young women in their late teens and early twenties. In children born to infected mothers, prevalence increased from 14% in infants younger than 6 weeks of age to 24% at 3-6 months. The blood-spot approach is an effective method for surveillance of HIV-1 in women and children, and for early identification of incidence of this infection in women of child-bearing age.