Rapid, simple serodiagnosis of murine typhus

The dot-blot enzyme-linked immunosorbent assay (dot-ELISA) was compared to latex agglutination (LA) and the Weil-Felix OX-19 test for the diagnosis of murine typhus using the indirect immunofluorescent antibody (IFA) test as the 'gold standard'. With a panel of 74 positive and 47 negative sera, the dot-ELISA was 98% specific and 74% sensitive at a cut-off value of the second dot. With acute sera, latex agglutination was 100% specific and 74% sensitive at a cut-off titre of > or = 1:64. Both tests were more sensitive than the OX-19 test, which was 98% specific and 56% sensitive at a titre of > or = 1:320. Both dot-ELISA and latex agglutination were comparable and the results were available within one hour of testing. The rapidity, ease in performance and minimal requirement for electrical instruments made these 2 tests suitable for the diagnosis of murine typhus in countries where sophisticated laboratory facilities are lacking.