By: Dr. Linda Jacobson, President, Ontario Shelter Medicine Association
This is a repeat of a blog Dr. Jacobson guest-wrote for the OSPCA recently. The content is mostly geared toward prospective adopters, but should be of interest to other shelter staff, including medical staff. (Photos – Toronto Humane Society).
FIV stands for “feline immunodeficiency virus”. This is a virus in the same group as HIV, but it is specific to the cat family and can’t cross over into people or other animals.
There are many misconceptions about FIV, the most extreme being that every cat with FIV is sick and/or highly contagious, and should be euthanized. This is not supported by the facts, and fortunately this kind of thinking is rarely encountered these days.
Let’s start with what an initial positive FIV test means, because this can cause a lot of confusion. The most common test is a point-of-care rapid test, conceptually similar to the COVID rapid antigen test. Unlike the COVID rapid test, though, it detects antibody, a footprint of the immune response to the virus, and not parts of the virus itself. This is important because, in a kitten under 6 months of age, a positive antibody test means that the kitten almost certainly obtained these antibodies by drinking milk from its (FIV-positive) mother. These kittens are nearly always truly FIV-negative, because it’s almost unheard of for this particular virus to pass directly from the mom to the kitten. Here’s some great information about this from the Kitten Lady.
If a cat has a positive antibody test after 6 months of age, in most cases they really do have FIV infection. FIV is usually spread through deep bite wounds, and is overwhelmingly a disease of adult cats, especially sexually active males.
One of the first questions adopters ask is, will this cat give FIV to my other cat/s?
The answer is no. FIV can’t spread easily. The virus dies very quickly outside the cat’s body, usually within minutes. Just living with another cat with FIV, in a normal home environment, does not result in spread. Even if cats don’t like each other, it’s extremely unlikely that their dislike will result in the kind of deep bite wounds that FIV requires to infect another cat. (This is, of course, assuming that the cats are spayed or neutered. If they are intact and breeding, that’s another matter altogether.) Check out Dr. Annette Litster’s webinar to learn more about her groundbreaking research about this.
Another question that is frequently asked is, what does this diagnosis mean for me and my cat? Does having FIV mean my cat is sick, or will definitely get sick at some point?
There’s good news here, too, but first the bad news. Cats with FIV do have the potential to develop immune deficiency, and this can lead to chronic or unusual infections. The good news is that many cats with FIV will never develop clinical immune deficiency.2 In my experience with shelter cats at Toronto Humane Society, when cats with FIV do have clinical signs of infection, it’s typically a mild intermittent cold, or sometimes an incision infection after a “dirty” surgery like dental extractions. We have just not seen the same kind of disease progression that do see in some cats with feline leukemia virus (a totally different virus with some similar features). And when our FIV-positive cats do get sick with regular cat ailments, they respond well to standard treatments.
Do FIV-positive cats make good companions?
Well, they are all different, so there’s no one answer. That said, there certainly is a “type” that we in the sheltering world all know and love. The “typical” FIV-positive cat is a big tom, with big cheeks, a can-do attitude, and a collection of scars from his life outdoors. Those who are comfortable around people are likely to be cats who were socialized when young, and were later lost or abandoned. They have big hearts and big personalities, and make wonderful and loving family members.
Should cats with FIV be managed differently from other cats?
Not really. What we want for all cats is regular veterinary visits, to be up-to-date on vaccinations and deworming, and to receive a high-quality, balanced diet. Good primary health care is particularly important for cats that might have immune deficiency. We also generally recommend that these cats should not have access to the outdoors, to limit their exposure to infectious diseases. However, the American Association of Feline Practitioners (AAFP) guidelines point out that, for cats that will be highly stressed with an indoor-only lifestyle, being allowed outdoors, including a working cat placement, can be considered. This does not pose a risk to other cats they may encounter – again assuming they are first spayed or neutered to prevent high-risk behaviours.
Adopters may worry that an FIV-positive cat will soon get sick and die. This is unlikely, as these cats typically have a normal lifespan. If they do develop signs of FIV-related immune suppression, it’s up to each family to decide how they want to proceed. There are a few medications that might help to suppress the virus, but the benefits for cats have not been proven as they have been in people. We counsel adopters to focus on maintaining a good quality of life for their FIV-positive cats, and that heroics are not required, although some families might choose to pursue intensive and expensive treatments. There should be no guilt involved in saying goodbye after you have given an animal a wonderful second chance – a good quality of life in a loving home.