Capture-ELISA for serum IgM antibody to respiratory syncytial virus

Abstract
SUMMARY: A four-component solid-phase capture enzyme immunoassay was set up to test for serum IgM antibody to respiratory syncytial (RS) virus and was compared with immunofluorescence assay (IFA).A total of 128 young children with acute respiratory infections were studied. Thirty-six were shown to be RS virus-positive by the detection of RS virus in nasopharyngeal secretions and 92 were RS virus-negative. A serum specimen was collected after admission to the hospital (days 0–4) and a further specimen was obtained during days 10–14. Out of 36 RS virus-positive patients, 28 (77·7%) were found to be positive for IgM by both capture-ELISA and IFA. Out of 92 RS virus-negative patients 5 (5·4%) were IgM-positive. Four false-positive results were obtained by IFA due to the presence of rheumatoid factor.The capture-ELISA was shown to be a reliable technique in detecting specific IgM antibody to RS virus.