March 28, 2023

We all love our cats and want to protect them at any cost.

Unfortunately, cats often get sick and sometimes it can be very difficult for cat owners to tell the difference between a minor issue and a serious health problem.

cat in hand

In this article we cover some of of the most fatal cat diseases that we think you should know about.

Without further ado, here is the list of the most fatal cat diseases:

Feline Immunodeficiency Virus (FIV)

fiv cats

Feline immunodeficiency virus (FIV) is a life threatening disease which has no effective treatment and is non-curable. The disease was first discovered in the mid-1980s in cats in the USA.

The feline immunodeficiency virus is mainly transmitted through bite wounds. This makes outdoor cats especially vulnerable as they very often get into fights over territory which usually end with bite wounds.

The virus is often referred to as cat HIV or cat AIDS because it has a similar effect on cats.

FIV works by attacking cells in a cat’s immune system, often targeting white blood cells. The damage caused by FIV eventually leads to a weakening of the cat’s immune system.

Feline immunodeficiency virus tends to shorten the infected cat’s lifespan considerably.

Symptoms of FIV in cats can include:

  • Poor coat condition
  • Persistent fever
  • Lack of appetite
  • Inflammation in the mouth and gums
  • Diarrhea
  • Seizures
  • Behavioral changes
  • Signs of neurological disorders

More about FIV available in the video below:

Feline Rabies

feline rabies

Rabies is a virus that attacks a cat’s nervous system, including the brain and the spinal cord. Cats usually get it from a bite from another infected cat.

Felines infected with feline rabies become less affectionate and keep away from humans and other cats in the household.

Cats infected with rabies may also exhibit the following symptoms:

  • Changes in behavior
  • Aggression
  • Drooling
  • Loss of muscle control, especially near the mouth
  • Trouble with swallowing

Feline rabies can be fatal if not treated before the symptoms appear. Once the symptoms appear, the infected cat usually dies within two-four weeks.

Feline Leukemia Virus

sick cat

Feline leukemia virus or FeLV is one of the most common diseases that affect cats. It is estimated that FeLV affects around 3% of all cats in the USA.

FeLV is also one of the most deadly cat diseases,  killing around 80% of infected cats within three years of diagnosis.

Feline leukemia works by damaging the immune systems of cats, leading to a failure of bone marrow.

The virus is usually transmitted through saliva, urine, or nose discharge. It can also be passed on from the mother to the kitten.

Cats that get infected by the virus usually become ill immediately, although the symptoms may not show up for several weeks.

fiv symptoms

Cats infected with FeLV exhibit some of the following symptoms:

  • Loss of appetite
  • Weight loss
  • Pale gums and other mucus membrane
  • Bladder, skin, or upper respiratory infections
  • Persistent Fever
  • Diarrhea
  • Breathing difficulty

Regular visits to the vet, vaccination, and a clean environment can prevent the chances of the virus being transmitted.

Chronic Kidney Disease (CKD)

cat kidney disease

Chronic kidney disease is the persistent loss of kidney function over time. With this disease, the kidneys slowly stop working over months or years as they lose the ability to remove toxins from the blood.

Among the many different kidney diseases that may affect cats, chronic kidney disease is the most common. The general percentage of cats older than 15 who suffer from chronic kidney disease is more than 30%.


CKD is usually caused by autoimmune diseases, cysts in the kidney, and genetics.

General symptoms of kidney failure in cats include:

  • Dehydration
  • Increased thirst
  • Lack of appetite
  • Lack of appetite
  • Diarrhea
  • Vomiting
  • Depression
  • Bad breath (halitosis)

Although there is no definitive cure for chronic kidney disease, there are treatments available that can help relieve the symptoms and prolong the lives of cats with this disease.

Feline Infectious Peritonitis (FIP)


Feline infectious peritonitis is a viral disease that affects wild and domestic cats. This disease is also referred to as a syndrome because some aspects of it are still not fully understood.

FIP is caused by certain strains of a virus known as the feline coronavirus. The feline coronavirus causes wide-spread and severe inflammation in cats’ bodies.

The resulting inflammation can lead to organ failure, persistent fevers, and an accumulation of thick yellow fluid in a cat’s chest or abdomen.

swollen cat

Early signs of FIP can vary but often include a rising and falling fever, loss of appetite, and energy loss.

Although there is no therapy that can help cure FIP, there are some treatments that can reduce the symptoms and slow down the progression of a cat’s decline.


cat diseases

When you think your beloved cat might be sick, every second counts. Some of the diseases we mentioned above tend to progress rapidly, so it’s always best to seek veterinary care at the first sign of trouble.

If you notice your feline is not acting quite like usual, schedule an appointment with your veterinarian. Your vet can identify any underlying medical issues and provide the right treatment for your cat.

Leave a Reply

Your email address will not be published.