The present invention describes methods for preventing IBS, reducing the likelihood of developing IBS and/or treating IBS by administering CDT inhibitors and/or CDT neutralizers to a subject in need thereof. The present invention also describes methods of eliciting a specific immune response and methods of vaccinating a subject to prevent IBS or to reduce the likelihood of developing or having IBS. The present invention further describes methods of diagnosing IBS by detecting the presence or absence of CDT or a CDT marker in a subject.
