Kaposi sarcoma-associated herpesvirus (KSHV) seroprevalence in population-based samples of African children: evidence for at least 2 patterns of KSHV transmission.

BACKGROUND Kaposi sarcoma-associated herpesvirus (KSHV) infection is endemic among adult populations in Africa. A prevailing view is that childhood transmission is primarily responsible for the high seroprevalence of KSHV among adults that is observed throughout the continent. However, few studies have directly examined children, particularly in locations where KS is not commonly endemic. METHODS Participants were children aged 1.5-8.9 years, including 427 children from a population-based sample in South Africa, 422 from a population-based sample in Uganda, and 567 from a clinic-based sample in Uganda. All serum specimens were tested by the same laboratory for KSHV antibodies with use of 2 enzyme immunoassays (against K8.1 and ORF65) and 1 immunofluorescence assay. RESULTS KSHV seroprevalence was 7.5%-9.0% among South African children and was not associated with age. In contrast, in the Ugandan population-based sample, KSHV seroprevalence increased from 10% among 2-year-old children to 30.6% among 8-year-old children (P(trend) < .001). In the Ugandan clinic-based sample, seroprevalence increased from 9.3% among 2-year-old children to 36.4% among 8-year-old children (P(trend) < .001). CONCLUSION Two distinct relationships between age and KSHV infection among children imply that KSHV transmission among children is not uniform throughout Africa and is therefore not always responsible for the high seroprevalence observed in adults. There are at least 2 patterns of KSHV transmission in Africa.