FIGURE 7.

Relationship among IFN-γ–producing PBMCs, level and duration of bacteremia, and diameter of lesion postinoculation between vaccine groups. The left graph summarizes the number of Ag-specific, IFN-γ–producing PBMCs collected at 3 wk after third vaccination, as estimate of cellular immunity available before challenge with O. tsutsugamushi. Vaccinees with the pKarp47 ×3 vaccine (group 3) had the highest IFN-γ–producing PBMCs, the lowest bacteremia, and the shortest bacteremic duration. The middle graphs depict the median levels of bacteremia and duration of bacteremic dissemination phase during acute disease, and the right graph depicts the diameter of the eschar lesion at day 12 per group (and dosage regimens).