Protective immunity to chlamydial genital infection: evidence from animal studies.

In all animal models for chlamydial infection, there is strong evidence for immunity to reinfection; however, immunity is only complete (ie, preventing infection) in the short term. In the long term, animals are only partially immune (ie, they can be reinfected, but infections are usually abbreviated and less intense than the primary infection). This review will target the mechanisms responsible for long-term versus short-term immunity and explore the roles of various components of the host response in immunity to chlamydial genital infection.