Talk to me about feline luekemia

[MonkeyPie]

I am in discussion with a woman that fostered a litter of kittens for the local shelter about adopting one of her gorgeous babies. He is negative for FL, but they think he will test positive soon because one of his brothers suddenly tested positive.

So tell me - what would this mean for me and this kitty? Other than keeping her inside and away from other kitties, does it require any special care?

This is him

 

[TooPatient]

Some interesting information -- especially the highlighted part.

link

What is feline leukemia virus?
Feline leukemia virus (FeLV), a retrovirus, so named because of the way it behaves within infected cells. All retroviruses, including feline immunodeficiency virus (FIV) and human immunodeficiency virus (HIV), produce an enzyme, reverse transcriptase, which permits them to insert copies of their own genetic material into that of the cells they have infected. Although related, FeLV and FIV differ in many ways, including their shape: FeLV is more circular while FIV is elongated. The two viruses are also quite different genetically, and their protein consituents are dissimlar in size and composition. Although many of the diseases caused by FeLV and FIV are similar, the specific ways in which they are caused differs.

How common is the infection?
FeLV-infected cats are found worldwide, but the prevalence of infection varies greatly depending on their age, health, environment, and lifestyle. In the United States, approximately 2 to 3% of all cats are infected with FeLV. Rates rise significantly—13% or more—in cats that are ill, very young, or otherwise at high risk of infection.

How is FeLV spread?
Cats persistently infected with FeLV serve as sources of infection. Virus is shed in very high quantities in saliva and nasal secretions, but also in urine, feces, and milk from infected cats. Cat-to-cat transfer of virus may occur from a bite wound, during mutual grooming, and (though rarely) through the shared use of litter boxes and feeding dishes. Transmission can also take place from an infected mother cat to her kittens, either before they are born or while they are nursing. FeLV doesn't survive long outside a cat's body—probably less than a few hours under normal household conditions.

What cats are at greatest risk of infection?
Cats at greatest risk of 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

Kittens born to infected mothers

Kittens are much more susceptible to infection than are adult cats, and therefore are at the greatest risk of infection if exposed. But accompanying their progression to maturity is an increasing resistance to FeLV infection. For example, the degree of virus exposure sufficient to infect 100% of young kittens will infect only 30% or fewer adults. Nonetheless, even healthy adult cats can become infected if sufficiently exposed.

What does FeLV do to a cat?
Feline leukemia virus adversely affects the cat's body in many ways. It is the most common cause of cancer in cats, it may cause various blood disorders, and it may lead to a state of immune deficiency that hinders the cat's ability to protect itself against other infections. The same bacteria, viruses, protozoa, and fungi that may be found in the everyday environment—where they usually do not affect healthy animals—can cause severe illness in those with weakened immune systems. These secondary infections are responsible for many of the diseases associated with FeLV.

What are the signs of disease caused by FeLV?
During the early stages of infection, it is common for cats to exhibit no signs of disease at all. However, over time—weeks, months, or even years—the cat's health may progressively deteriorate or be characterized by recurrent illness interspersed with periods of relative health. Signs can include:

Loss of appetite

Slow but progressive weight loss, followed by severe wasting late in the disease process

Poor coat condition

Enlarged lymph nodes

Persistent fever

Pale gums and other mucus membranes

Inflammation of the gums (gingivitis) and mouth (stomatitis)

Infections of the skin, urinary bladder, and upper respiratory tract

Persistent diarrhea

Seizures, behavior changes, and other neurological disorders

A variety of eye conditions

In unspayed female cats, abortion of kittens or other reproductive failures

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I understand there are two stages of FeLV infection. What are they?
FeLV is present in the blood (a condition called viremia) during two different stages of infection:

Primary viremia, an early stage of virus infection. During this stage some cats are able to mount an effective immune response, eliminate the virus from the bloodstream, and halt progression to the secondary viremia stage.

Secondary viremia, a later stage characterized by persistent infection of the bone marrow and other tissue. If FeLV infection progresses to this stage it has passed a point of no return: the overwhelming majority of cats with secondary viremia will be infected for the remainder of their lives.

How is infection diagnosed?
Two types of FeLV blood tests are in common use. Both detect a protein component of the virus as it circulates in the bloodstream.

ELISA (enzyme-linked immunosorbent assay) and similar tests can be performed in your veterinarian's office. ELISA-type tests detect both primary and secondary stages of viremia.

IFA (indirect immunofluorescent antibody assay) tests must be sent out to a diagnostic laboratory. IFA tests detect secondary viremia only, so the majority of positive-testing cats remain infected for life.

Each testing method has strengths and weaknesses. Your veterinarian will likely suggest an ELISA-type test first, but in some cases, both tests must be performed—and perhaps repeated—to clarify a cat's true infection status.

How can I keep my cat from becoming infected?
The only sure way to protect cats is to prevent their exposure to FeLV-infected cats.

Keep cats indoors, away from potentially infected cats that might bite them. If you do allow your cats outdoor access, provide supervision or place them in a secure enclosure to prevent wandering and fighting.

Adopt only infection-free cats into households with uninfected cats.

House infection-free cats separately from infected cats, and don't allow infected cats to share food and water bowls or litter boxes with uninfected cats.

Consider FeLV vaccination of uninfected cats. (FeLV vaccination of infected cats is not beneficial.) Discuss the advantages and disadvantages of vaccination with your veterinarian. FeLV vaccines are widely available, but since not all vaccinated cats will be protected, preventing exposure remains important even for vaccinated pets. FeLV vaccines will not cause cats to receive false positive results on ELISA, IFA, or any other available FeLV tests.

I just discovered that one of my cats has FeLV, yet I have other cats as well. What should I do?
Unfortunately, many FeLV-infected cats are not diagnosed until after they have lived with other cats. In such cases, all other cats in the household should be tested for FeLV. Ideally, infected and non-infected cats should then be separated to eliminate the potential for FeLV transmission.

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How should FeLV-infected cats be managed?


Confine FeLV-infected cats indoors to reduce their exposure to other infectious agents carried by animals, and to prevent the spread of infection to other cats in the neighborhood.

Spay or neuter FeLV-infected cats.

Feed nutritionally complete and balanced diets.

Avoid uncooked food, such as raw meat and eggs, and unpasteurized dairy products because the risk of food-borne bacterial and parasitic infections is much higher in immunosuppressed cats.

Schedule wellness visits with your veterinarian at least once every six months. Although a detailed physical examination of all body systems should be performed, your veterinarian should pay special attention to the health of the gums, eyes, skin, and lymph nodes. A complete blood count, serum biochemical analysis, and a urine analysis should be performed at every examination. Additionally, your cat's weight should be accurately measured and recorded, as weight loss is often the first sign of deterioration.

Closely monitor the health and behavior of your FeLV-infected cat. Alert your veterinarian to any changes in your cat's health immediately.

There is no scientific evidence that alternative, immunomodulator, or antiviral medications have any positive benefits on the health or longevity of healthy infected cats.

How long can I expect my FeLV-infected cat to live?
It is impossible to accurately predict the life expectancy of a cat infected with FeLV. With appropriate care and under ideal conditions, infected cats can remain in apparent good health for many months, although most succumb to a FeLV-related disease within two or three years after becoming infected. If your cat has already experienced one or more severe illnesses as a result of FeLV infection, or if persistent fever, weight loss, or cancer is present, a much shorter survival time can be expected.

My FeLV-infected cat died recently after a long illness. How should I clean my home before bringing in a new cat?
Feline leukemia virus will not survive outside the cat for more than a few hours in most environments. However, FeLV-infected cats are frequently infected with other hardier infectious agents, and these may pose some threat to a newcomer. Thoroughly clean and disinfect or replace food and water dishes, bedding, litter pans and toys. A dilute solution of household bleach (4 ounces of bleach in a gallon of water) makes an excellent disinfectant. Vacuum carpets and mop floors. Any new cats or kittens should be properly vaccinated before entering the household.

Can people become infected with FeLV?
Epidemiological and laboratory studies have failed to provide evidence that FeLV can be transmitted from infected cats to humans. Regardless, FeLV-infected cats may carry other diseases. At greatest risk of infection are elderly or immunosuppressed people (e.g., those with AIDS, or receiving immunosuppressive medications such as chemotherapy), infants, and unborn children. It is recommended that pregnant women, people with suppressed immune systems, the very young, and the very old avoid contact with FeLV-infected cats.

 

[MonkeyPie]

I'm actually worried about the last bit, about transfer to humans. I do NOT want Micah to get sick.

 

[TooPatient]

Even if your kitty tests positive, it doesn't mean she'll have it forever. A number of infected cats are able to fight it off and are okay (and naturally immune for awhile).


Info from Cat Fancy

When a cat is exposed to FeLV, there are four possible outcomes. In about 30% of cats, an effective immune response is produced and the infection is resisted. These cats then become naturally immune to FeLV infection for an unknown period of time. In about 40% of cats, the virus is successful and the cat eventually becomes persistently infected and excreting virus in its saliva. Another 30% of cats do not produce immunity but also do not become persistently infected immediately. In these cats, the virus hides in the bone marrow for up to 30 months. Eventually, these cats either overcome the virus or become persistently infected. Finally, some cats can develop latent or sequestered infection. This probably happens to less than 5-10% of cats. These cats, whose virus is hiding in sites such as the bone marrow, will rarely be contagious and are unlikely to develop illness. They will not test positive on routine testing. In general, young cats, especially those under 4 months of age, have the least ability to mount an effective immune response and so are most susceptible to FeLV.

 

[athenaworth]

I just had a false alarm with my new kitten, and from what I read about it, if kittens get it they can usually fight it off with antibodies that adult kitties don't have. There's hope.

 

[rhbgirl24]

I adopted a kitty when I first got my own apartment. She was positive, but I didn't know this. A little over a year old, she collapsed and I rushed her to the vet. She was well progressed but didn't show any normal symptoms up until that day - none of the weight loss, sluggishness, nothing. It was a horrible experience, I will still cry over it, and this was 5 years ago. We could have kept her and they would have done biweekly transfusions, but I couldn't see making her go through that for me, so I could have her a little longer. We had her put down that night.... less than 12 hours from the collapse.

It was one of the most heartbreaking things I have EVER gone through. She was a fantastic cat. I adopted my dear black kitty Raven a few months after my Luna's death and I MADE SURE she was negative. I never ever ever want to go through that again. Plus its so communicable that I won't even have her socialize with other animals, or stay where others are without knowing they tested negative. I constantly check my Raven's gums to make sure they are nice and pink the experience traumatized me that much!

 

[MonkeyPie]

I'm so sorry rhb That's terrible.

I would hate to NOT adopt this kitty though, when he could otherwise have a happy life with me. I know a lot of people would turn him down, despite his beauty, just because of the leukemia, and I think he deserves a chance. I just don't know.

I'm going to meet him Friday unless something changes my mind between now and then. I'll be doing a lot of research to be certain!

 

[rhbgirl24]

He is gorgeous! Yes, do your research. I know there can be carriers that will never progress into full blown symptoms. But remember, even with that - you wouldn't be able to ever have another cat with this little one......

Best of luck, I'm hoping that there was just a false positive somewhere in the testing and that beauty is all clear. I wouldn't want you to have to go through all that heartbreak....

 

[MonkeyPie]

I'm crossing my fingers, too. He hasn't tested positive, but a litter mate did, and they think it's guaranteed that this one will have it, too. I'm hoping they will be wrong!

If I take him, he will be tested again in January.