Health & Nutrition | Cats | September 26, 2018

What is Feline Leukemia?

Feline leukemia (FeLV) is a complex retrovirus found in cats. It is the second biggest health threat to cats, surpassed only by trauma. It kills about 85% of cats infected by it within three years. However, 70% of cats who are exposed to it will be able to eliminate it entirely from their bodies.

FeLV attacks the immune system and makes the cat more susceptible to a variety of other diseases, cancers, and a multitude of immunodeficiency complications. Cats with FeLV are left with little chance of defending themselves against the bacteria and viruses that surround them on a daily basis. It is not uncommon for cats with FeLV to suffer from anemia, major dental issues, upper respiratory infections, blindness, diarrhea, and a host of other health problems.

Is it contagious?

Feline leukemia is quite contagious and can be found in saliva and nasal discharge. It can be transferred via casual contact between cats. Sharing food, water, mutual grooming, bite wounds, in utero and less commonly via a shared litter box. It is a fairly hardy virus that can survive outside the body for about two hours.

Is my cat at risk?

As with most other diseases outdoor cats, stray cats, and feral cats have a higher chance of getting, and passing this virus along. Kittens and senior cats are also more susceptible because their immune systems are already weaker. Healthy household pets are more likely to fight it off. There is a vaccine for FeLV, and although it is not 100% effective, it is recommended for any cats that may come into contact with other cats who may be carrying this virus.

Cats that are infected with this virus can either succumb to it or develop an immunity. There are three possible outcomes for cats that are exposed to FeLV. A cat can fight the infection off and become completely immune to it. They can become a carrier that never gets sick but can infect other cats, or they are unable to fight the infection and become terminally ill.

How do you know if your cat has FeLV?

Feline leukemia can be detected with a simple blood test, commonly referred to as a “snap” test. This test will show if the cat has any FeLV antibodies. Because this disease is so complex the chance of getting a false positive is commonplace. All positive “snap” tests need to be confirmed with a more intensive blood workup. Even this does not confirm the disease 100%. If the second test comes back positive as well, it needs to be redone in about six weeks. This is to see if the cat has fought the disease off or not.

What happens if your cat is diagnosed?

Most cats will die within three years of contracting this virus. Their life may be complicated with health issues, or they may live most of their life relatively symptom-free. Kittens who are born with the virus, or are infected by their mother shortly after birth, will usually die by their second birthday, and many die well before that. Over the last six years, I have taken in twelve FeLV positive kittens, and not one of them lived past their second birthday. Several died well before that. Most of them lived happy, healthy lives and only developed symptoms within two to three days of dying.

While a diagnosis of FeLV can be devastating it is important to remember that your cat can live for several years, hopefully, symptom-free. FeLV positive cats need regular vet visits to ensure that any secondary infections are dealt with right away. They need to be kept away from other cats, not only for their own well being but so that they don’t infect other cats.  If you have other cats though, get them vaccinated so the cats can remain together.  You don’t want to cause undue stress for your FeLV cat by removing him from his feline friends.  FeLV cats need to be kept indoors, be stress-free, and a healthy diet is crucial.

Feline leukemia is an ugly disease and with no cure available, prevention is key.