By Lauren Giplin

It’s been a very busy year for most rescues – while COVID-19 and its related “stay home” orders have spurred an uptick in demand for adoption, it has also indirectly lead to a population boom in the outdoor cat community. The shuttering of vet clinics in March, April and May left TNR (trap/neuter/release) workers unable to spay and neuter feral cats during the peak of kitten season.

As a result, feral cats who would have been fixed in the spring instead went on to have a litter (or two) over the subsequent warm weather months. Rescuers are overwhelmed not only by the volume, but also by the percentage of cats and kittens entering shelters with life-threatening medical conditions.

If you’re a cat lover, you’ve probably heard of FIV, FIP, or FeLV. Maybe you thought they were all kind of the same thing – or at least similar. Maybe you thought they were all death sentences, and that cats with these illnesses should be avoided. The trepidation is understandable – they’re all scary-sounding abbreviations that begin with “F.” Let’s shed some light on what these illnesses are and how they differ from one another.

FIV (Feline Immunodeficiency Virus)

FIV Is often the easiest of the three viruses for humans to wrap our minds around, because it’s very similar to the “human” version of the virus: HIV. As in humans, the virus attacks and weakens the cat’s immune system, making her more vulnerable to other viruses and infections.

How is FIV contracted? FIV is most commonly spread by deep bite wounds. For this reason, it is more common in cats who roam (or used to roam) outdoors, where aggressive fighting and territorial behavior is commonplace. Kittens can also contract FIV from a FIV+ mother, although this is not always the case.

Big Daddy contracted FIV during his days on the streets. He’s cozy in his new home now!

What are the symptoms? Cats in the early stages of infection with FIV usually display enlarged lymph nodes and fever. Typically, these symptoms are temporary, and may not be noticeable. Lingering symptoms include those normally correlated with clinical immunodeficiency, including poor coat appearance, persistent low-grade fever, inappetence, and inflammation. FIV+ cats are more vulnerable to common bacteria, so they’re more likely to experience frequent colds and infections of the respiratory system, bowel, or urinary tract.

Is there a test for FIV? Yes! Cats adopted through FCS are given a combination ELISA test which detects both FIV and FeLV (more on that later). While these tests are not 100% accurate, a positive diagnosis can be confirmed by a more specific IFA test.

Is it contagious? FIV is much less contagious than originally thought. The experts at Cornell University’s College of Veterinary Medicine say that in a stable indoor environment, it is very unlikely for FIV to spread from an infected cat to an FIV-negative cat.

Is it curable? Currently, there is no known cure for FIV. However, there is a wide variety of effective treatments available for the symptoms that FIV+ cats experience, and when monitored appropriately, FIV+ cats can live just as long and healthily as normal cats.

What does it all mean? If you’re considering bringing an FIV+ cat home to foster or adopt, here’s the straight poop! FIV+ cats mostly live very normal lives, and they can safely cohabitate with non-FIV cats. It’s recommended that FIV+ cats see the vet a minimum of every 6 months (versus every 12 months for a “healthy” cat), so you might need to anticipate a little bit more stress on your wallet. You also will want to become familiar with the symptoms of various infections, as these can be more serious for your FIV+ kitty than they would be for an FIV-negative kitty.

If you’re fostering or adopting through FCS, don’t worry! We’ll provide you with tons of information about your new FIV+ kitty to make sure you’re properly prepared to care for her. Not only do you get a new feline companion, you get to give yourself a pat on the back for choosing a kitty that a lot of other people will overlook. Go you!

FIP (Feline Infectious Peritonitis)

FIP, which is caused by a mutation of a benign feline coronavirus (no, not COVID-19!), is the most deadly of the three viruses discussed in this article. The common feline coronavirus is much like the common cold viruses that humans experience, and the vast majority of cats infected with it experience mild to no symptoms. But for a small percentage of cats (as low as 1%, according to our friends at the VCA), that “no-big-deal” virus transforms inside of the body and becomes FIP. FIP is most common in young cats under 2 years of age, and historically it has always been a fatal disease.

How is FIP contracted? FIP occurs when a benign feline coronavirus mutates inside of a cat’s body. Scientists and veterinarians aren’t quite sure yet why some cats develop FIP while most others don’t, so the idea of “transmission” is difficult to apply to this virus.

What are the symptoms? FIP can present in two forms: a “wet” or effusive form that is characterized by the accumulation of fluid in the abdomen or chest, and a “dry” form that does not cause the aforementioned fluid accumulation. Both forms of the disease cause lethargy, decreased appetite, persistent fever, inflammation of organs, and anemia. Some cats will also experience ocular or neurological effects.

Is there a test for FIP? Currently, there is no test for FIP. There is a test which detects the presence of feline coronavirus antibodies, but many cats have these – regardless of whether or not they have FIP – so this is not considered a proper metric for diagnosing FIP. Veterinarians make FIP diagnoses based on a combination of presenting symptoms and analysis of bloodwork.

Is it contagious? No! While the feline coronavirus is contagious, it is benign to the vast majority of cats, and most cats will be exposed to it at some point in their lives. Cats with FIP can (and frequently do) safely cohabitate with non-FIP cats without a risk of transmission.

Is it curable? This is a bit of a gray area. Up until very recently, the answer was a definitive “no.” Historically, FIP has been considered fatal, and veterinarians have had only palliative care and euthanasia to offer their FIP-diagnosed patients. Recently, a promising treatment emerged in an off-label use of the human Ebola (and experimental COVID-19) treatment, Remdesivir, which was shown in a small clinical trial to cure 80% of FIP cases.

Ruth was diagnosed with FIP in July. She is flourishing under treatment!

Unfortunately, for a plethora of bureaucratic reasons, the treatment has not made it to market for veterinary use in the U.S. Currently, small local advocacy groups are working to connect owners of FIP-infected cats with this effective medication by any means possible. At the time of writing this, an FIP+ cat under the care of FCS is in her final 3 weeks of treatment with this off-label medication, and she is flourishing!

What does it all mean? It’s unlikely that you would adopt a cat knowing that she has FIP. Since there is no test, and the symptoms can be difficult to detect in their early stages, there is no way to know which cats will develop FIP. If you or someone you know has a kitty who has been newly diagnosed with FIP, don’t panic! Contact your nearest cat rescue organization and see if they might be able to connect you to someone who can help explain the treatment options to you.

FeLV (Feline Leukemia Virus)

If FIV is kind of the “no big deal” of the big scary “F” abbreviations while FIP is the “big bad,” FeLV can be looked at as somewhere in the middle. Contrary to its name, FeLV bears very little similarity to human forms of leukemia. It is an infectious disease which, similarly to FIV, weakens the immune system of infected cats. However, the severity of symptoms is graver in FeLV cats than in those with FIV, and FeLV can (and often does) eventually lead to cancer.

How is FeLV contracted? Cats contract FeLV via prolonged exposure to the urine, saliva, blood, or feces of an infected cat.

What are the symptoms? Many cats in the early stages of infection with FeLV show no symptoms at all. As the disease progresses, FeLV causes loss of appetite, weight loss, poor coat appearance, anemia, inflammation of the gums, persistent fever, enlarged lymph nodes, and increased susceptibility to respiratory and digestive infections.

Is there a test for FeLV? Yes! The aforementioned ELISA combo test that detects FIV also detects FeLV. As with FIV, the test is not perfect — but results can be confirmed with an IFA test.

Luna has FeLV and is loving life!

Is it contagious? While FeLV is not as contagious as scientists initially thought, the answer is yes. There is a risk of transmission even in stable, indoor environments, although it is small and requires prolonged interaction (grooming, sharing of food dishes, litter box, beds, etc.). Cats are most susceptible to FeLV when they are under one year of age, but cats of any age can contract FeLV under the right circumstances. An effective FeLV vaccine is available and can help to drastically reduce the chance of transmission to healthy cats.

Is it curable? Unfortunately, there is currently no cure for FeLV. However, new treatments are constantly emerging. While the documented life expectancy for FeLV+ cats is only 2.5 years post-diagnosis, the consensus in the animal welfare community is that FeLV+ cats can and do live longer with proper care, nutrition, and monitoring.

What does it all mean? Adopting or fostering an FeLV+ cat or kitten is an act of kindness and compassion. Because they tend to be stigmatized and overlooked, many shelters euthanize FeLV+ cats due to lack of placement. So when you adopt or foster an FeLV+ cat, you are truly saving that animal’s life! Cats with FeLV often develop strong bonds with their caretakers, and the relationship can be extremely rewarding.

That said, the care of FeLV+ cats can be complicated, and prospective adopters should be prepared to monitor their cat’s symptoms carefully. Even minor colds and infections should be treated quickly with veterinary guidance. Certain supplemental treatments can help to strengthen an FeLV+ cat’s weakened immune system, and a reputable veterinarian will likely be able to point you in the right direction.

If you’re considering adopting or fostering an FeLV+ cat through FCS, you’re in luck! Our team members are very knowledgeable about FeLV, and we’ll be here to help you and your new companion every step of the way. FCS currently has multiple FeLV cats under its care, all of whom are flourishing in foster homes and bringing their humans lots of joy.

If you are interested in fostering or adopting a cat with one of these diseases, or if you just want to learn more, please reach out to us! We need people like you!


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