Patent ID: 7741059

Claim:
A method of detecting antibodies or antigen-binding antibody fragments that specifically bind an Ehrlichia chaffeensis polypeptide in a test sample, comprising: (a) contacting a purified polypeptide comprising SEQ ID NO:1, 2, 4, or 5 with the test sample, under conditions that allow polypeptide/antibody complexes to form; and wherein the purified polypeptide consists of less than about 50 contiguous naturally occurring Ehrlichia chaffeensis amino acids, and wherein the purified polypeptide does not specifically bind Ehrlichia canis antibodies in the test sample; (b) detecting the polypeptide/antibody complexes; wherein the detection of the polypeptide/antibody complexes is an indication that antibodies specific for Ehrlichia chaffeensis are present in the test sample.