Chlamydophila felis is a gram-negative rod-shaped coccoid bacterium. it has a cell wall which lacks peptidoglycan. It is an obligate intracellular parasite that lacks the ability to replicate autonomously [Becker, 1978]. Chlamydophila is a genus within the family Chalmydiaceae of the order Chlamydiales. The genome of Chlamydophila felis has been sequenced recently [Azuma et al 2006]. There is extensive homology between Chlamydia species. The membrane contains important families of proteins; the major outer membrane proteins (MOMPs) and polymorphic outer membrane proteins (POMPs). The organism attaches to sialic acid receptors of cells. It has a unique pattern of replication within cells, involving reticulate bodies (RB) and elementary bodies (EB). The latter represent the infectious forms of the micro-organism that are released following cell lysis. Some Chlamydophila felis isolates appear to contain plasmids and this may be related to their pathogenic ability. [Everson et al, 2003].