What is FeLv?
FeLV stands for feline leukemia virus. As the name implies, it is a viral infection of cats that affects a cat’s immune system and bone marrow.
How does a cat get FeLv?
FeLV is passed along from cat to cat through bodily fluids and requires repeat exposure (i.e. bite wounds, mating, some cats are born with FeLv if they have a positive mother). Repeat exposure can also include cats sharing a household or living together in the same room at a shelter. Mutual grooming, sneezing, the sharing of dishes and litter pans can all spread the virus to non-FeLv vaccinated cats. (winnfelinehealth.org)
FeLv is typically not spread in urine or feces. It can be transmitted from a mother cat to a kitten in utero or during nursing.
How long can FeLv+ (feline leukemia positive) cats live?
FeLv+ cats are documented as having lived 22+ years- as long as cats who test negative.
40% of the cats exposed to FeLV will successfully shed the virus from their systems. (greenbriervet.com) This occurrence is more common with an adult cat, then it is for a kitten. If the virus is not shed, there are two other outcomes. 30% of the time, the cat will become persistently infected. In this case, both the ELISA test and IFA test will be positive for feline leukemia and remain positive for the cat’s whole life. Cats that are infected will typically remain healthy two to three years after exposure and then eventually succumb to a FeLV-related disease such as lymphoma, leukemia, or an untreatable infection. 15% of FeLV+ cats do, however, make it past the four year mark.
Life With Cats shares, “There are people who believe that euthanizing cats that are positive for FeLV is helping to prevent an epidemic against the whole feline population. This is incorrect. An epidemic of feline leukemia would only be likely to happen in a hoarding situation. Cats that live outside (even in feral colonies) do not live in close enough proximity to each other to spread the virus. For instance, it is estimated that only 2-3% of cats in the United States carry the virus at any given time.”(vet.cornell.edu)
Should I euthanize a cat or kitten who has tested positive for FeLv+?
No! As previously stated, 40% of cats exposed to FeLv will successfully shed the virus from their systems. Kittens who are tested too young can test falsely positive for the virus. Tests can be wrong. In addition, Life With Cats shares:
“When you have a household of both feline leukemia negative and positive cats as I do, you can do two things. First, you can keep the cats separated. In other words, the positive cats can be kept in one room or on a separate floor to prevent exposing the negative cats to the virus. This is the safest option. Second, you can have the cats that tested negative vaccinated against feline leukemia. This is what I opted to do and it has, so far, been successful. Those cats that are negative stayed negative. The vaccine is not considered 100% effective but it can work by creating an immune response to the virus that will protect the exposed cats. Some vets will suggest euthanizing a cat that carries FeLV, though not all vets do. If you opt to euthanize, you must realize that you are destroying a cat that only has the potential to be ill but is not necessarily currently ill or in any distress. Doing this is not giving the cat’s immune system the chance to possibly shed the virus.” Also, if you euthanize a cat because of a positive test(s), you will never know if the cat could have been one of the many that may have lived a long, healthy, quality life.
How serious is FeLv+?
40% of the cats exposed to FeLV will successfully shed the virus from their systems. (greenbriervet.com) See above question/answer for additional details. Less than 3% of all cats ever test positive for FeLv, and again, not all positive tests are accurate as many cats will shed the virus or later test negative.
Can FeLv+ transfer to humans?
No! FeLv only impacts cats – it cannot transfer to humans, dogs or others in anyway, shape or form.
Is FeLv the same as FIV in cats ?
No. FeLv and FIV in cats are different.
FeLV is a retrovirus that only infects cats. The virus spreads by inserting copies of its own genetic material into the host cat’s cells. The cells are then transformed into cancer cells or cells which do not function the way that they should. (greenbriervet.com)
FeLV is passed along from cat to cat through bodily fluids and requires repeat exposure such as that which occurs in cats sharing a household or living together in the same room at a shelter. Mutual grooming, sneezing, the sharing of dishes and litter pans can all spread the virus. FeLV is sometimes confused with FIV, which is more like human HIV. With FIV, white blood cells called T helper cells are destroyed, leading to a depression of the cat’s immune system. FIV is mostly spread through bite wounds and mating and so is more common in unneutered males. (winnfelinehealth.org)
If a cat/kitten tests positive for FeLv is it possible that they will test negative at a future date?
Yes! 40% of the cats exposed to FeLV will successfully shed the virus from their systems. (greenbriervet.com)
Should I adopt a FeLv+ cat? What do I need to know?
There is no specific treatment for FeLV, so most of the treatment of FeLV-positive cats involves supportive care. Because FeLV-positive cats can have weaker immune systems, they do need to be treated for upper respiratory infections (or any illness/infection) right away, if this occurs. Some veterinarians tend to recommend the need for dentals at a younger age than other cats, as a measure of keeping the cats in top health.
FeLV+ cats should always be kept indoors for their own safety.
Click here to read one individual’s experience with adopting/raising an FeLv+ cat along side her healthy (negative tested) cats.
Can FeLv+ cats live with those who have tested negative?
A negative and positive cat can certainly live in the same house, as long as they do not have contact with each other (i.e. separated). If cats share the same space/environment, veterinarians recommend that negative cats be vaccinated against FeLv annually.
Can FeLv cats have a good life?
Yes! FeLV-positive cats can live perfectly happy lives, and they deserve to do so. If you share your home with an FeLV-positive cat(s) it’s important to understand that it’s a possibility the cat may have a shorter life span (but this is not always the case, as many cats live 14+ years- the average life span of a cat who tests negative). It is important to remember that FeLv+ cats should be taken to a veterinarian if any health issues arise, as quick treatment is essential for their well-being and ongoing health.