Comparison of an indirect fluorescent-antibody test with an enzyme-linked immunosorbent assay for serological studies of Lyme disease

Abstract

An ELISA was compared with an indirect fluorescent antibody (IFA) for its ability to detect antibodies to the Lyme disease spirochete in sera of naturally infected humans, dogs and white-footed mice and experimentally infected Swiss mice. Of the 123 sera analyzed, 95% reacted similarly in both tests. For 36 human sera, the correlation coefficient (r = 0.47) for logarithmic transformations of IFA and ELISA titers was significant at P < 0.01. Within each mammalian species, mean titers for IFA and ELISA antibodies were within 3-fold. Comparisons of different naturally infected mammals revealed relatively higher average titration endpoints in both tests for patients with Lyme disease. Human sera also had the widest range of titers. Both methods proved satisfactory for serological confirmation of prior spirochetal infections.