"Immune Med Scrub Typhus Rapid" tests the antibodies against Orientia tsutsugamushi in the patient's plasma, serum or blood using Lateral Flow ImmunoChromatographic Assay.

After applying diluted serum, plasma or blood to the test device for IgM, the patient's sample first reacts with gold conjugated anti-human IgM antibody and for IgG, with gold conjugated protein A. After that, each reactant diffuses on the membrane to the recombinant antigens marked as test lines. If positive, the test line turns to red color because the antigen-antibody-gold conjugate complex is formed on the test lines.