Direct polymerase chain reaction for detection of human immunodeficiency virus in blood spot residues on filter paper after elution of antibodies: an adjunct to serological surveys for estimating vertical transmission rates among human immunodeficiency virus antibody-positive newborns

Blood spot residues on filter paper circles from which antibodies have been eluted remain suitable for follow-up polymerase chain reaction to detect human immunodeficiency virus (HIV) provirus. A method has been developed for specimen processing and nested polymerase chain reaction amplification with a single tube. HIV-positive specimens can be detected by simple, direct electrophoresis of amplified material to a single copy of provirus. The procedure is particularly suited for survey purposes to estimate rates of vertical transmission of virus among HIV antibody-positive newborns, in whom virus loads may be low.