Feline leukemia (FeLV) is a common disease in cats. This immune-weakening disease increases a cat’s chance of getting other diseases, such as blood disorders and cancer. Here’s everything you need to know about this disease.

What is Feline Leukemia?

FeLV is a virus that affects 2 to 3 percent of cats in the U.S. Cats who are already sick are more likely to catch FeLV. Since a vaccine was developed, however, the cases of the disease are far less than in the past 25 years.

A cat with FeLV can infect other cats through their saliva, urine, feces, nasal secretions, and milk. Cats may also contract it through a bite or during grooming. In rare cases, the virus is spread through feeding dishes and litter boxes.

According to the Cornell Feline Health Center, “Cats at greatest risk of FeLV infection are those that may be exposed to infected cats, either via prolonged close contact or through bite wounds. Such cats include cats living with infected cats or with cats of unknown infection status, cats allowed outdoors unsupervised where they may be bitten by an infected cat, and kittens born to infected mothers.”

Young cats are far more likely to contract FeLV because their immune systems are not yet strong enough to fight the virus.

Signs and Symptoms of Feline Leukemia

Because there are many different signs or symptoms for FeLV, it’s important not to jump to conclusions if your cat shows any one symptom. Only a vet would have the ability to diagnose FeLV. Here are common symptoms of FeLV:

  • Loss of appetite
  • Poor coat condition
  • Anisocoria
  • Skin infections
  • Bladder and respiratory tract infections
  • Oral disease
  • Seizures
  • Swollen lymph nodes
  • Anemia
  • Diarrhea
  • Jaundice

Because FeLV is caused by a virus, a cat can become infected and show no symptoms at all. It’s also possible for a coat to have all symptoms. The middle ground is where a cat may only have a few symptoms but is otherwise healthy or may live with a compromised immune system.

As the disease develops, there are six stages. The first four stages are where a cat may still be able to fight off the infection. If the disease progresses into the fifth or sixth stage, the cat’s body can become overwhelmed by the disease.

How is Feline Leukemia Diagnosed?

Veterinarians use one of two different blood tests to diagnose FeLV. Each of them detects a protein in the virus called FeLV P27. Oftentimes, a vet will do both tests to get an accurate reading.

Treatment for Feline Leukemia

In the United States, the most common approved treatment includes the use of Lymphocyte T-Cell Immunomodulator. This is a low toxicity medication that has been shown to increase the lymphocyte numbers and Interleukin 2 production of animals.

In Europe, the most common treatment includes the use of Interferon Omega and has been shown to decrease FeLV mortality rates from 50% to 20%.

How to Prevent Feline Leukemia

There are some risk factors for cats that are more likely to contract the virus. First, as we said before, kittens are more likely to contract FeLV. Second, outdoor cats are more likely to get the virus. Indoor cats have a very low likelihood of contracting the virus. Lastly, multi-cat households are more at risk because of shared living spaces, litter boxes, and food dishes.

To prevent FeLV in your cats, vaccinate them against it. It’s the only sure proof way to prevent this illness. Keep your cats indoors and away from cats that might have the virus. If your cat likes to be outdoors, make sure it’s only under your supervision.

The prognosis for cats with FeLV can be scary, but it’s important to note that your cat still has a chance to lead a normal life for a while. The survival time for cats with FeLV is about two and a half years. Your veterinarian will work closely with you on a care plan if your cat is ever diagnosed with FeLV. And remember, if you ever get a kitten, they should be vaccinated against FeLV before coming to your home.