As an attmpt to find a serologic evidence of Lyme disease, we studied prevalence of antibodies to Korean isolate strain(Konkuk-1) of Borrelia burgdorferi among febrile patients in Korea, 1990-1992. Sera collected from 5119 subject were examined
by
using
imunofluorescence antibody test(IFA).
The IFA showed that 415(7.1%) of 5119 sera had the titer of ≥ 1:16. We also found that males have the higher seropositive rate than females and that seropositivity is subjects older than 60 years. Seropositives to B. burgdorferi were the most
prevalent
in May and November. Seventy-three percent sera of seropositives to B. burgdorferi crossreacted with Rickettsia tsutsugamushi antigen by IFA.
There are currently no accepted criteria for positive westernblots in Lyme disease. In our analysis of sera reactive with B. burgdorferi(n=29), R. tsutsugamushi(n=19) and control subjects(n=30), the best discriminatary ability of test criteria
was
obtained b requiring at least 2 of the 8 statistically significant IgM bands(32, 35, 37, 41, 55, 60, and 75 kDa) or by requiring at least 2 of the 5 statistically significant IgG bands(37, 41, 60, 75, 83 kDa). When these definition were tested,
IgM
blot
had a sensitivity of 59% and a specificity of 96% : the IgG blot had a sensitivity of 62% and a specificity of 94%.
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