Feline Infectious Peritonitis (FIP) is a deadly disease for cats. It is caused by a type of virus known as feline coronavirus and affects 5-10% of all cats. Not all cats who carry the corona virus will develop the devastating symptoms of FIP. It is believed that FIP is either caused by an immune response to the coronavirus or that the virus mutates into FIP. Cats that are positive for FIP often show no symptoms and will carry this it forever. The active disease can appear weeks to years after the cat becomes positive and is nearly always rapidly fatal. There is no vaccination and no cure for FIP. A few years ago St Francis Animal Rescue had a litter of kittens left at the back door and all were FIP positive. Although they were healthy and playful, a majority of shelters would have quickly euthanized them. Several of our shelter volunteers had no other cats and adopted these tiny kittens. All are alive today and loving pets but still could develop symptoms.