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Oz: Feline leukemia virus

Make sure that the vaccinations that were given to your cat contain the FELV component.

Cancer has always been one of the most challenging areas in both human and veterinary medicine. One of the most common types of cancers in cats is feline leukemia, which is actually a result of a viral infection. Luckily with the right management this cancer may be prevented.

Feline leukemia virus (aka FELV) is a virus belongs to the retrovirus family. The disease spreads easily either by a contact between a carrier cat to unexposed cat, or from a carrier pregnant queen to her kittens through the placenta or in the milk. The virus can not be transmitted from cats to dogs, nor to humans.

Feline leukemia virus attacks the body’s lymphoid tissue (part of the immune system) and may cause either lymphosarcoma-tumors in various internal organs or leukemia (cancer of the white blood cells in the blood). The virus also leads to anemia and general weakness of the immune system, which alters the cat’s ability to fight any sort of infection.

The severity of the disease depends mainly on the timing of the exposure to the virus, and the strength of the cat’s immune system. The stronger the cat’s immune system is, the more likely that it will overcome the infection. Kittens younger than six months of age are the most prone to developing persistent infection.

The disease starts to be manifested by clinical sign only two to four years after the exposure. This fact makes it hard to prevent the transmission of the disease. Unfortunately your cat can get sick by being in contact with another cat that evidently seems healthy.

There are many different symptoms for the disease, depending on the location of the cancer developed. The symptoms showing will be related to the body system affected, for an example-intestinal tumor can lead to vomiting, changes in the stool, weight loss etc.

The disease is diagnosed and confirmed by a blood test. Most veterinary clinics carry an in-house test that can give you a result within only few minutes. Otherwise the blood can be sent to a laboratory.

If left untreated the infected cat will die within one to two months from the onset of the clinical disease. Most of the cancers that are caused by feline leukemia virus respond well to chemotherapy but only prolong the cat’s life by a few months.

Fortunately there is a vaccine available against feline leukemia virus. The vaccine is not risk free, and there is no vaccine that guarantees complete protection, but since people started to routinely vaccinate their cats against FELV, the prevalence of the disease has been markedly reduced. Please note, that some of the feline annual vaccines combination do not contain the vaccine against FELV.

Make sure that the vaccinations that were given to your cat contain that component. If your cat got vaccinated with a vaccine that does not contain the FELV component, it can be given separately. In other words, do not assume that your cat is vaccinated for FELV just because it got an annual vaccine, make sure the vaccine also included that part.

Kittens, as being the most prone to severe infection, should be vaccinated twice—the first vaccine at the age of eight to nine weeks followed by a booster three to four weeks later, and regularly as adults.

If you decide to adopt a new cat, I also recommend to first check the cat for the disease. Especially if there are other cats in the household or if you are planning on letting your cat roam around freely outdoors. If you do adopt an infected cat , it is not an immediate death sentence. This cat needs to get the same health care as any other cat, including routine vaccinations (for the other component of the vaccine, not the FELV part, because that will not be effective). It is important to keep infected cats away from other cats.

Because infected cats are more prone to severe infections, a routine physical exam by a veterinarian is recommended at least every six months.

Please consult your veterinarian about more information on feline leukemia virus and how to protect your furry friend from it.