Early diagnosis of human immunodeficiency virus in infants using polymerase chain reaction on dried blood spots in Botswana's national program for prevention of mother-to-child transmission

Background: Botswana has high antenatal human immunodeficiency virus (HIV) prevalence (33.4%). The public health system provides free services for prevention of mother to child transmission of HIV (PMTCT) and antiretroviral therapy, which can reduce vertical HIV transmission from 35% to <5%. Infant HIV diagnosis is challenging in resource-limited settings, and HIV prevalence among HIV-exposed infants in Botswana is unknown. Dried blood spot (DBS) polymerase chain reaction (PCR) provides a feasible method to assess PMTCT programs and identify HIV-infected children. Methods: We trained staff in 15 clinics and a hospital to obtain DBS on HIV-exposed infants age 6 weeks to 17 months receiving routine care. Samples were sent to the national HIV reference laboratory. Roche Amplicor 1.5 DNA PCR testing was performed. Results: Between June-December 2005, 1931 HIV-exposed infants age 6 weeks to 17 months were tested for HIV, of whom 136 (7.0%) were HIV infected. Among infants <= 8 weeks old, 27 of 544 (5.0%) were HIV infected. Among infants tested in clinics (primarily during routine health visits), 65 of 1376 (4.7%) were infected; among infants tested in the hospital, 71 of 555 (12.8%) were infected. Conclusions: Collection and testing of DBS was successfully integrated into routine infant care in the public health system. HIV prevalence among infants in the Botswana PMTCT program is low. National expansion of infant DBS PCR in Botswana is planned.