ELISA modules and full kits are produced for most Rickettsia species, with Bartonella, Coxiella and Orientia coming this year. The coating antigens consist of purified proteins in concentrations specific for IgG or IgM testing. Patient absorbance values are compared with a cut-off calibrator, which is derived from testing of sera from healthy blood donors and confirmed by western immunoblot testing where necessary. Kits include all necessary assay components, color-coded and bottled at working strength, and full instructions for use. For specific details see the specific sections.