Volume 87, Issue 1
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



We evaluated the diagnostic accuracy of two broadly reactive rapid immunochromatographic tests (ICTs) for detection of IgM and IgG against by using archived acute-phase serum samples from 102 patients with laboratory-confirmed scrub typhus, and from 62 archived serum samples from patients with other causes of fever as a negative control. These ICTs were constructed by using a mixture of recombinant proteins: 1) C1, a chimeric protein containing epitopes of the 56-kD antigen from Karp and TA763 strains; 2) Ktr56; and 3) Gmr56. Sensitivities of the ICTs for detection of IgM and IgG were 90.2% (95% confidence interval [CI] = 84.4–96.0%) and 86.3% (95% CI = 80.9–93.8%), respectively. Specificities were 85.5% (95% CI = 73.9–92.2%) and 96.8% (95% CI = 90.3–100%), respectively. Both assays were more sensitive and specific than the standard immune immunofluorescence assay for the early diagnosis of scrub typhus.


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  • Received : 15 Sep 2011
  • Accepted : 25 Mar 2012
  • Published online : 02 Jul 2012

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