This is a list of the ten worst cat diseases or illnesses together with some detail and links to more information. It is my list because there is no official list. You may well disagree with it and you may wish to add to it or change list around, which is fine. I have listed them in order of nastiness so the top disease is the worst of the worst and the bottom listed disease or illness is the least worst of the worst.
This disease is caused by a virus. This, of course, is not strictly a feline disease because it occurs in nearly all warm-blooded animals. Rabies is a fatal disease. Not only is it fatal the symptoms are nasty and the disease stigmatises the cat because when the cat has this disease he or she is a danger to people. The disease damages the cat’s image in the eyes of people and provides people who do not like the domestic cat with ammunition to criticise it. Another reason why rabies is particularly horrible is that when a cat is suspected of having rabies for whatever vague reason then it is liable to be killed and a post-mortem carried out on the brain. So if a cat is provoked and then attacks aggressively, the cat is liable to be branded rabid, which is very unfortunate. This bundle of factors is the reason why heads the latest. You can read more about the symptoms of this nasty disease on this page.
Feline Infectious Peritonitis (FIP)
This disease is caused by a virus and is common in wild and domestic cats. The disease is spread from cat to cat. Less than 1% of infected cats develop the secondary fatal disease. Many cats have a mild infection but become carriers. It is estimated that in catteries 80% and 90% of cats are positive for antibodies to the virus meaning that at some stage the cat had the virus. Once a cat develops a secondary form of this disease he will die. So this disease is common, is contagious and is fatal when fully developed. These are the reasons why it is ranked high in this list. You can read about this disease on this page.
Feline Leukemia Virus (FeLV)
The feline leukaemia virus accounts for about half of all internal cancers most of which are lymphomas, which is cancer of the lymph system which is part of the immune system.
This virus is also associated with other serious cat diseases including anaemia, feline infectious peritonitis, spinal cord cancers and toxoplasmosis. The feline leukaemia virus depresses the immune system which contributes to a higher incidence of secondary diseases. This virus can cause many health problems both indirectly and directly. It is associated with cancer of the blood, which is leukaemia and leukaemia of the lymph system. Read more about this disease (written in plain language)
This disease is also called feline distemper and is caused by a virus. The word “distemper” is misleading because it has no relationship to distemper in dogs. The virus that causes the disease attacks white blood cells. A white blood cell count confirms diagnosis. There is a 90% mortality rate for kittens infected with this virus. Secondary infections develop which can also kill the cat. Most cats are exposed to panleukopenia during their lifetime. Read more here and here (first hand experience).
Feline Lower Urinary Tract Disease (FLUTD) and kidney disease (I will bundle the two together because they are linked).
This includes urinary tract infections. This disease is caused by a bacterial infection. Cystitis, which is inflammation of the bladder, is another term commonly used. Lower urinary tract problems are by far the major health concern of a cat owner. There is a high level of recurrence as well. It can occur in domestic cats of all ages.
Kidney failure occurs when the kidneys are unable to remove waste products from the blood. Kidney failure can be acute, meaning happening quickly and severely, or it can be chronic meaning on-going and gradually over a long period of time which is typical in older cats. Chronic renal failure is a major cause of death in the domestic cat.
Because urinary tract diseases and kidney disease is commonplace amongst the domestic cat population and because many domestic cats die of kidney failure, I have rated this feline illness as one of the worst. You can read more on this page. More.
Feline Immunodeficiency Virus (FIV)
This is caused by a virus. The virus is related to the same virus that causes AIDS in people. However, each virus is specific to the species. It affects 2% to 4% of cats in the USA in the general population, it is believed. Cats with chronic FIV suffer from a variety of illnesses some serious. For an example, about half have chronic mouth conditions. There is no effective treatment. The virus is shed in saliva. Therefore the incidence of this disease is highest amongst outdoor cats. Read more and please use the search box above this post.
Feline Viral Respiratory Disease Complex. This includes upper respiratory infections and I include conjunctivitis
The various diseases under this heading are highly contagious. They can be a serious illness. The disease can spread rapidly in a cattery or shelter or in a home where there is more than one cat. They are one of the most common infectious disease problems. There is a 50% mortality rate among kittens. One frequently sees pictures of stray cats who have contracted an upper respiratory infection leading to a secondary bacterial infection in the eye which ultimately destroys the eye leaving the cat blind. An acute viral respiratory infection may be mild or severe and it can be fatal. The disease is transmitted by direct contact with infected discharge from the eyes, mouth, nose and contaminated objects. Two major viral groups are responsible for this disease and one of them is the herpes virus group which includes feline viral rhinotracheitis (FVR). Almost all cats infected with FVR are carriers. A cat carrying the disease when stressed may exhibit symptoms of the disease. Read more. And about pink eye. And first hand experience. Please search as there are many more articles.
Mouth disease – gingivitis – periodontal disease – gum disease-feline gingivitis stomatitis
If you visit websites run by veterinarians you will notice that mouth diseases commonly gum disease are one of the most common health problems that they have to deal with. Gum disease is not life-threatening but it can be chronic if neglected and cause great discomfort for the cat. Veterinary treatment involves a general anaesthetic, which, on my calculation results in one in four hundred cats dying so there is an indirect life-threatening risk. Because it is so commonplace is listed here. You can read more on this page. Gingivitis picture.
Parasites-Cat Fleas and Ear Mites
The ubiquitous cat flea is extraordinarily commonplace and a constant nuisance to both cat and cat owner. The flea bite allergy is quite serious and causes blistering of the skin, acute to mild discomfort in the domestic cat and is difficult to manage. Also, the cat flea is difficult to manage and prevent. Because of its ubiquitous nature the cat flea is listed here. Ear mites are extremely uncomfortable to the cat. They often go untreated, one of the more you can move the date of their or cat owners like to treat them themselves in my opinion is unwise. There are, of course, many other parasites that are found in an on the domestic cat that I had selected these two is the worst. Fleas picture and please search as there are many pages.
I am referring to an allergic reaction to an allergen. Allergic reactions in cats are rather mysterious, I feel. This is because there are so many potentials for an allergic reaction. Their are allergens everywhere. A cat may be allergic to something in his food or something in the carpet that creates a contact allergy or indeed something in the air. There are hundreds of possible causes and diagnosis can be extremely difficult while at the same time an allergy can cause extreme discomfort in a cat. Allergies cause unpleasant physical reactions. The cat’s immune system overreacts. Allergens enter the cat’s body through the lungs (in respect of an allergen in the air), the digestive tract (something in the food), by injection (flea bite allergy or vaccinations, for example), or absorption through the skin (causing dermatitis for example). Feline allergies and please search.