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 immunodeficie

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 immunodeficie