FIV or Feline Immunodeficiency Virus is a much-misunderstood virus believed to affect 2.5-4.4% of cats globally. In the past, cats that have tested positive for FIV have been euthanised, but the more we learn about this condition the more apparent it has become that FIV cats can live happy and comfortable lives.

Here are the most common questions about FIV answered.

Is FIV fatal?

No - by itself, FIV is not a life-threatening disease. The virus has a very slow effect on a cat's immune system, potentially weakening it over several years, and sometimes making that cat more vulnerable to secondary infections in the long-term. Every cat's immune response is different however, and the right environment is the key to maintaining good health in an FIV cat; a balanced diet and a happy and suitable home. Many FIV positive cats live into their senior years and have a lifespan similar to that of non-FIV cats.

Is FIV very contagious?

No. FIV is actually very difficult to pass on, being spread mainly through deep bites. This is why it is most common among unneutered Tom cats, particularly strays, who are prone to serious fights over territory. Neutering greatly reduces the chances of transmission, and FIV positive cats who are happy to co-exist with other felines pose a minimal risk, with many people keeping both FIV positive and negative cats in the same household to no issues.

Can humans catch FIV?

Absolutely not! FIV is a species-specific virus that can be transmitted to felines only, and even this is difficult.

Which cats are most at risk of contracting FIV?

Unneutered male cats who are allowed to freely roam outside are most at risk of contracting FIV, as they are most prone to fighting with other unneutered male cats - and FIV is often spread through deep bites. At Catcuddles, we have never encountered a cat who was neutered when they developed FIV. This is one of the many reasons that neutering is essential for your cat's health, and should be undertaken before you let them outside for the first time.

Do FIV cats need special care?

FIV cats do not need daily medication or any special care as such. Their owners simply need to do their utmost to maintain good health in their FIV cats and keep their exposure to infections minimal. A high quality, balanced diet, and a stress-free environment, in addition to regular vet checks and worming and flea treatments, is key.

It has also been suggested that raw or uncooked meats should not be fed to FIV positive cats due to the potential presence of harmful bacteria, and that hunting live prey should be discouraged. A vet who is up to date on the most current FIV research is also very important.

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What are the symptoms of FIV?

Cats usually present with only mild symptoms following initial infection by FIV, and some cat owners may never discover that their cat has contracted the virus at all. In the first weeks or months, FIV may manifest in symptoms such as lethargy, a mild fever or enlarged lymph nodes. Once the initial infection phase has passed, there are no specific signs associated with FIV. The gradual weakening of a cat’s immune system over time, however, may result in a greater susceptibility to infections such as cat flu, stomach upsets, and so on.

Do FIV Positive cats need to be kept indoors?

At Catcuddles, we do generally recommend keeping FIV positive cats indoors to eradicate any risk of the virus being transmitted to neighbouring cats or strays in the area. As FIV is very difficult to pass on, however, providing the cat in question is neutered, the risk may be only be small.

For example, whether a cat continues to be defensive towards other cats after being neutered and whether there a lot of unneutered cats roaming in the area around the home may be factors that dictate to what extent an FIV cat will pose an infection risk to other cats.

There is also some debate about whether keeping FIV cats indoors-only reduces risks to their health from secondary infections. At Catcuddles, we feel that it’s better to be safe than sorry and that in a controlled, indoor environment, the pathogens and infections that a FIV positive cat will come into contact with will be limited.

Other organisations, such as the FIV Cat Project, do not deem this necessary, and view outdoor access as potentially stress-reducing, and therefore, important for the health of FIV cats.

Installing cat-proofing in your garden may provide a perfect solution to these issues - allowing your FIV positive cat outside space whilst restricting their access to any neighbouring or visiting cats.

Should FIV cats be vaccinated?

At Catcuddles, we typically do not vaccinate FIV cats, as their more vulnerable immune systems may increase the chances of a negative reaction to vaccines and the viruses that they introduce to the body. Many of the FIV cats that we rehome are also indoor cats and the only cat in the household, meaning they are unlikely to be exposed to the viruses that vaccines typically protect against.

There is some debate on this subject, however, and some vets feel that it is because FIV cats are more at risk to infections that they should be vaccinated. If an FIV cat is allowed access to the outdoors, or is sharing their home with other cats, particularly cats that have suffered cat flu infections in the past and may continue to be carriers for the virus, the potential benefits and risks involved in vaccination may need to be considered more carefully.

Can kittens contract FIV?

Kittens can contract FIV if they are born to an FIV positive mother, however, this is very rare, and is something that usually occurs only in large feral cat colonies. Kittens also often initially test positive for FIV, only to test negative at a later date. This is because the kittens have inherited their mother’s antibodies and the standard FIV test used by vet practitioners works by detecting the presence of antibodies, rather than the virus itself. As the kittens begin to grow older, the antibodies fade, leading to a negative test result. It’s imperative that a young kitten is not diagnosed as FIV positive on the basis of a single test in the early weeks or months of life, as this is unlikely to be accurate.

Is there a vaccine to protect against FIV?

An FIV vaccine does exist, however, it is not currently available in the UK. This is because the vaccine was unable to offer full protection against all strains of the virus, and could lead to cats testing falsely positive for FIV for life, since standard FIV tests detect the presence of antibodies, rather than the virus itself. There are also far less medically invasive and effective preventative measures to protect against FIV - like neutering your cat before you let them outside for the first time.

Why is FIV so misunderstood?

One major reason for misunderstandings about FIV may be the experiences of veterinary and animal care professionals with stray FIV positive cats. Living on the streets can take a big toll on any cat's health, as strays suffer from a poor diet, hunger, the cold, and often frequent untreated wounds caused by fighting with other cats. For an FIV cat, whose immune system is, as explained, a little more vulnerable than most, years spent homeless can take a more dramatic toll, causing a decline in health that would not be seen in an FIV cat living protected in a home. Encountering only unwell FIV positive cats, and never meeting the many happy and healthy FIV cats living in homes worldwide, may have painted an incorrect picture for vets and animal care professionals - that all of these felines are sickly. You can read more about this on the 1000 FIV Cat Project website.

In reality, no-kill charities have been successful in restoring even ex-stray FIV positive cats to health; these special cats simply need a good diet and quality of life, and to be shielded a little more than most from any potential risks to their health. Environment, rather than the virus itself, is what is most significant here, and careful and considered decisions about long-term care.

Another reason for misunderstandings about FIV may be the stigma around Aids or HIV, and FIV's reputation as 'feline aids', or outdated scientific studies which are still relied upon by some vets.

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