Patent ID: 8658387

Claim:
A method of distinguishing between animals that have been vaccinated with inactivated Ehrlichia canis cells that (1) have been infected with Ehrlichia canis and animals that have been vaccinated with inactivated E. canis cells that (2) have not been infected with E. canis , the method comprising: (a) contacting individual biological samples from one or more animals vaccinated for E. canis with one or more purified wild-type E. canis polypeptides that do not specifically bind to antibodies that are a component of the animals' immune response to an inactivated E. canis cell vaccine, wherein the one or more purified wild-type E. canis polypeptides specifically bind to antibodies that are a component of the animals' immune response to an E. canis infection; and (b) detecting whether antibodies in the one or more samples specifically bind to the one or more purified wild-type E. canis polypeptides; wherein if antibodies in the one or more samples specifically bind to the one or more purified wild-type E. canis polypeptides, then those animals have been infected with E. canis ; and (c) differentiating animals that have been infected with E. canis from animals that have not been infected with E. canis , based on the results of step (b); whereby animals that have been vaccinated with inactivated E. canis cells that (1) have been infected with Ehrlichia canis and animals that have been vaccinated with inactivated E. canis cells that (2) have not been infected with E. canis are distinguished.