Indirect hemagglutination (IHA) is commonly used for serodiagnosis of
melioidosis. However, in endemic areas, high background titers in normal populations and occasional low titers in patients with septicemic
melioidosis prompted a search for a more sensitive and more specific method of serodiagnosis. An indirect fluorescent-antibody test for
immunoglobulin M (
IgM) specific antibody to Pseudomonas pseudomallei was more sensitive and more specific, but fluorescence microscopes are rarely available in the endemic areas. An
enzyme-linked
immunosorbent assay (ELISA) for
IgM antibody is an attractive alternative. An indirect ELISA for
IgM antibody (
IgM ELISA) and an
IgM antibody capture ELISA for
melioidosis were developed. Both tests, together with IHA, were evaluated for 153 serum specimens from blood donors and 16 serum specimens from 16
melioidosis patients. It was found that IHA, the
IgM ELISA, and the
IgM antibody capture ELISA had sensitivities of 88, 88, and 75%, respectively, with specificities of 97.4, 92.2, and 91.5%, respectively. When IHA was combined with
IgM ELISA, a sensitivity of 100% and a specificity of 95.4% were obtained. The
IgM ELISA and IHA should be used in combination for serodiagnosis of
melioidosis.