Evaluation of an Enzyme-Linked Immunosorbent Assay Based on Araraquara Virus Recombinant Nucleocapsid Protein

Laboratory diagnosis of hantavirus cardiopulmonary syndrome (HCPS) in Brazil has been performed mostly by a detection of IgM antibodies to recombinant antigen purified from Sin Nombre virus and Andes Virus (ANDV). Recently, a recombinant nucleocapsid (rN) protein of Argentina virus (ARAV), a Brazilian hantavirus, was Obtained in Escherichia coli. To evaluate ARAV rN as antigen for antibody detection, serum samples from 30 patients front Argentina seropositive for hantavirus were tested. All samples were positive for IgG and IgM by enzyme-linked immunosorbent assay (ELISA) using either ARAV rN or ANDV rN antigens. In Brazil, six of 00 serum samples from patients With suspected HCPS (10%) were positive for IgM by ELISA Using ARAV rN antigen and 7 were positive Using ANDV rN antigen. For results obtained with 90 serum samples analyzed by IgM ELISA with ANDV rN antigen, the sensitivity of the IgM ELISA using ARAV rN antigen was 97.2%,, the specificity was 100%, the positive predictive value was 100% and the negative predictive value was 98.1%. The results show that ARAV rN is a Suitable antigen for diagnosis Of hantavirus infection in Brazil and Argentina.