Your support of FIP research at the Center for Companion Animal Health (CCAH) over this last year has been tremendous and much appreciated. This last year has seen a number of advances in our knowledge of FIP and eventual cures. We documented that many cats have a natural resistance to FIP virus, but this resistance increases with age and cannot be explained by simple genetic differences. Rather, resistance is what we call polygenic, and involves many different genetic pathways, any one of which can be used in a given cat at a given time to eliminate the infection. Our research also indicates this immunity is not always permanent and some cats can become susceptible that were once resistant. We learned inbreeding is one of the most important genetic causes of decreased resistance to FIP. We also discovered that the FIP virus attacks only a single cell in the body, a peritoneal-type macrophage, and the infection spreads from macrophage to macrophage and not as free virus in the blood. Virus infected macrophages spread the infection to other organs, and can even enter the brain and eyes in some cats and cause neurologic or ocular disease. Infected macrophages in cats destined to develop FIP also cause a generalized suppression of normal immunity through some sort of signaling, thus assuring the virus’ own survival. Cats that are resistant to FIP do not manifest this suppression.