Evaluation of an IgG enzyme-linked immunosorbent assay for dengue diagnosis

Background: The hemagglutination inhibition (HI) test has been one of the s tandards, with the IgM antibody capture ELISA (MAC-ELISA), for the diagnosi s of dengue virus infections. The spread of dengue throughout the world and the increasing number of cases to be tested makes an ELISA-format test for IgG antibodies to replace the HI test highly desirable. Objectives: Evalua te the use of the IgG-ELISA as a substitute for the HI test in dengue diagn osis. Study design: Paired serum samples defined as being from primary or s econdary dengue virus infections by HI, were tested by an ELISA that detect s IgG antibodies. The correlations of titers and serologic interpretations between these two tests were examined. Results: The IgG-ELISA showed a low correlation with the HI in primary infections, and a higher correlation in secondary infections because of the influence of IgM antibodies in the HI t est. Nevertheless, IgG ELISA titers could be reliably associated with prima ry or secondary infections when analyzed by days after onset of symptoms, a nd can be used to characterize the immune response after flavivirus infecti ons. Conclusion: The combination of the IgM and IgG ELISAs may be used to s erologically diagnose dengue virus infections, since the IgG ELISA can subs titute for the HI test in characterizing the immune response to dengue viru s infections. (C) 1999 Elsevier Science B.V. All rights reserved.