The Feline Leukemia Virus (FeLV) affects the cat’s blood, causing various blood diseases. The virus also suppresses the cat’s immune system, making it harder to protect against infection by bacteria, viruses or fungi found in our everyday environment that wouldn’t affect healthy cats. However, feline leukemia does not have to be a death sentence; if appropriately diagnosed and treated, cats can live for many years with good quality of life.
How is FeLV transmitted?
The FeLV virus is transmitted through direct contact from cat to cat. The primary route of transmission is through saliva and nasal secretions, but it is also present in the urine and feces of infected cats. Cat-to-cat transfer can occur through bite wounds, but also through grooming. The virus only lives outside its host for a few hours, and because of this, transference through shared use of litter boxes and food dishes is not as common, but it can occur.
Which cats are at risk?
Cats living with infected cats, or with cats with an unknown infection status, are at the greatest risk for contracting the virus. Kittens and young adults are more susceptible than older cats. It appears that resistance to the virus increases with age.
Feline leukemia symptoms
Infected cats show one or more of the following symptoms:
– pale gums
– yellow color in the mouth and whites of eyes
– enlarged lymph nodes
– bladder, skin, or upper respiratory infections
– kidney disease
– weight loss and/or loss of appetite
– poor coat condition
– recurring or chronic illness
– progressive weakness and lethargy
– fever
– diarrhea
– breathing difficulty
How is FeLV diagnosed?
FeLV is diagnosed through a blood test called an ELISA test, which tests for the presence of FeLV antigens in the blood. This test is highly sensitive and can identify cats with very early infections. Many of these cats will manage to clear the infection within a few months and will subsequently test negative. A second blood test called IFA detects the second phase of the infection. Cats who test positive generally remain infected for life and have a poorer long-term prognosis.
A new rapid test, the FeLVCHECK Ag ELISA, was introduced earlier this year and has made it even easier to screen for FeLV. It detects the virus quickly and accurately, without needing special equipment.
A safer vaccine for at risk cats
Approved in late 2024, Nobivac® NXT FeLV, was introduced by Merck Animal Health. It uses cutting-edge RNA technology, and it is non-adjuvanted, meaning it is less likely to cause inflammation or tumors at the injection site.
The FeLV vaccine is considered a core vaccine by the Feline Veterinary Medical Association, but I would recommend discussing your individual cat or kitten’s risk with your veterinarian. If you decide to vaccinate against FeLV, insist on this new non-adjuvanted vaccine.
Living with feline leukemia
There is currently no cure for feline leukemia. Treatment is focused on treating symptoms caused by the virus.
Vets are using new viral load tests to monitor how much virus is in the body. These tests help determine the amount of virus present in a cat’s blood, indicating the stage of infection and understanding the progression of the disease, which can then determine treatment strategies.
Conventional medical treatment may include steroids, antiviral drugs, chemotherapy drugs, and blood transfusions. All of these treatments come with often significant side effects, and will require assessing the risks of the treatment versus the benefits. If successful, these treatments can put a cat in remission.
Holistic treatments such as high doses of vitamin C, homeopathic remedies or Chinese Herbs can help boost the cat’s immune system. Do not use any of these modalities without consulting with a veterinarian trained in holistic therapies.
Prevention and protection
Never bring a new cat or kitten into a household with existing cats without testing for the virus first.
Regular veterinary check ups to monitor your cat are crucial and allow you to get ahead of any complications.
Keeping your cat indoors is the only way to completely protect your cat from contracting the feline leukemia virus.
Image by Aneta Rog from Pixabay
Thanks for this information. Hopefully, one day, there might be a cure for this.