detection of vertical transmission of human immunodeficiency virus type 1 by a commercial polymerase chain reaction assay in a prospective study a commercial polymerase chain reaction pcr system was compared with a conventional procedure based on pcr and hybridization with a radiolabeled probe for the detection of human immunodeficiency virus hiv infection in 131 blood samples from 80 children born to hivseropositive mothers twentythree of these children were hiv infected the sensitivity and specificity of the commercial assay as compared with the conventional pcr procedure were 100 and 951 respectively this commercial method simplifies the performance of the conventional pcr technique and can be used to detect hiv type 1 vertical transmission