FELINE LEUKEMIA VIRUS VACCINATION
Whitecourt Veterinary Clinic
Box 1769
Whitecourt, Alberta T7S 1P5
Telephone: 780-778-5767 - Fax: 780-778-5452
wctvet@telusplanet.net
Feline Leukemia Virus (FeLV) was one of the leading causes of death in cats until the development of a vaccine in the mid-1980's.
What is
Feline Leukemia Virus (FeLV)?
Feline leukemia virus (FeLV) is one of the most important viruses infecting cats. FeLV tends to become a persistent infection and depresses the immune system of cats. FeLV is an important cause of anemia in cats and can cause cancers of several types.
How common is FeLV?
FeLV infection is found worldwide. Because cats become persistently infected and may carry the virus for long periods before showing any clinical signs, your cat may be exposed to FeLV without you realizing it.
What diseases does the virus cause?
FeLV invades and replicates in various cells of the cat's immune system and blood-forming cells, as well as other cells. The results include suppressed immune responses making the FeLV-infected cat more susceptible to chronic or recurrent infections. Death or dysfunction of infected cells may give rise to enteritis (inflammation of the intestine) or anemia (low red blood cell numbers). FeLV infection can also change the genetic code in infected cells. The genetic code programs the cell's functions. Changes in genetic code as a result of FeLV infection may sometime later give rise to cancers such as leukemia, lymphosarcoma or other tumors. These tumors may affect one or many tissues, organs or body sites.
FeLV is usually fatal. Studies have shown that 80-90% of FeLV-infected cats will die within 3 to 4 years of the initial diagnosis.
Is there any treatment for FeLV infection or disease?
There is currently no specific treatment for FeLV-infected cats. Treatment is usually
aimed at easing the symptoms and treating secondary infections. Most FeLV-infected cats
will eventually die of diseases related to their infection or require euthanasia.
Is there a test for FeLV infection?
Special blood tests have been developed. Most tests are designed to detect the presence
in the cat's blood for components of the virus. In general the test is very reliable
although occasionally a misleading result occurs. In some situations it may
be necessary to confirm
infection with the virus through repeated blood testing.
Does my cat need to have a blood test before vaccination?
For the vast majority of cats, this is highly recommended. Remember not all FeLV-infected cats that blood test positive become sick. Some FeLV-infected cats may not show signs of disease for months or even years.
How safe is the vaccine?
FeLV vaccines have been specially developed so that they do not contain any infective virus material and they are considered very safe. You are unlikely to see any ill effect of the vaccine apart from some mild sluggish behavior a day or two after the vaccine is given. A very few cats may have a mild allergic reaction. Most vaccine reactions occur almost immediately and your veterinarian will provide appropriate treatment. If you are concerned that your cat is experiencing an abnormal reaction in the hours or days following any vaccination, please call us.
How effective is FeLV vaccination?
FeLV vaccines have now been available for many years and they have been continuously improved. They are clearly helpful in preventing infection with FeLV and thus controlling FeLV-related disease. Unfortunately, no vaccine is 100% protective. Where possible do not allow your cat, particularly a kitten, to come into close contact with known FeLV-infected cats or cats of unknown vaccination history.
How often is revaccination necessary?
Revaccination is necessary in the initial course of vaccines to provide strong lasting immunity. Even so, immunity does decline over time and your veterinarian will advise you of the recommended revaccination schedule for your pet.
This client information sheet is based on material written by Ernest E. Ward Jr., DVM.
© Copyright 2002 Lifelearn Inc. Used with permission under license. October 16, 2003.