A Point-of-Care Assay for the Detection of Spotted-fever group and Typhus group Rickettsia.

The objective of this study is to develop a robust, field-grade, screening assay for the differential diagnosis of infection by Spotted Fevers (e.g. Rocky Mountain Spotted fever, Boutonneuse fever) and Typhus (Epidemic and Endemic forms) causing rickettsial bacteria. Scrub Typhus (Orientia tsutsugamushi) will be used as a reference control and may be incorporated into the final assay. The test will utilize lateral flow (dipstick) chromatography incorporated into a unique, triplex, cassette that enables the simultaneous screening of Spotted Fever, Typhus and Scrub Typhus group organisms. The proposed immunochromatographic assay would be a very useful for point-of-care screening and as differential diagnostic test to assess individuals presenting with symptoms of infection. In this Phase 1 study we shall evaluate the ability of a panel of rickettsia-derived antigens from the families of pathogens listed above to function as the basis of an IgM/IgG serodetection system. We will then construct prototype assays that will be evaluated against samples from individuals with confirmed infections. Further development of the assay would take place in a Phase 2 study.