The rare but often fatal disease of cats known as Feline Infectious Peritonitis is caused by a coronavirus FIP virus and is similar antigenically to the virus that causes feline enteritis or panleucopaenia (FEVC) – a relatively common non-fatal disease of cats. The progress of the disease in a freshly infected cat, as with many other infectious diseases depends on the dose of virus and the immune defence status of the cat. The virus is generally spread by the oral route from an infected cat or the motions of other cats, or inanimate objects such as food bowls, and is seen mainly in cats less than two years of age. It is probable that most cats exposed to the virus will recover with a strong immunity unless their immune system is compromised. The virus produces two forms of the disease “wet” and “dry”. Both forms of the disease initially produce a dull looking cat with a raised temperature. In the wet form, there may be a fluid build-up in the abdomen and sometimes difficulty with breathing. The symptoms in the dry form are variable including – persistent high temperature, weight loss, depression, lack of coordination, nervous signs and eye disease. Some cats remain carriers after infection and may serve as the reservoir for transmission to other cats.
Diagnosis of the disease can be difficult because the blood test for the disease is not very specific for this virus. It should be remembered however that this disease is rare in cats. No reliable vaccine is available in the UK yet, but one is licensed in the US which gives 75% protection. If your cat is a known carrier, keeping the cat indoors and separate from non-infected cats is advised. As the disease is more serious when present with Feline Leukaemia Virus (FeLV), routine vaccination against this virus is strongly recommended.