Feline immunodeficiency virus (FIV) in cats: a guide

A diagnosis of feline immunodeficiency virus – more commonly known as FIV – in your cat isn’t as scary as it might sound. An FIV-positive cat can live happily for many years with no sign of illness. The virus is also non-transferable to humans

Feline immunodeficiency virus – more commonly known as FIV – is a condition that weakens a cat’s immune system. It makes cats susceptible to other infections in a similar way that HIV does in humans.

FIV is among the most widespread cat diseases worldwide. In the UK, an estimated 4% of cats have the virus.

When first infected with FIV, a cat develops a short-lived illness as the virus spreads to the lymph nodes around their body. They may have a fever and swollen glands, lose their appetite and become lethargic for a few weeks. However, it’s not unusual for owners to miss these initial signs of FIV infection.

The cat then enters an asymptomatic stage of FIV infection, which can last for months or even years. They look and behave just like an uninfected cat, but can still spread the virus. Over time, FIV weakens the cat’s immune system by targeting white blood cells. This eventually makes them susceptible to secondary infections from bacteria, viruses and other germs – even ones that are normally harmless to cats.

The infected cat is now at risk of developing a range of diseases, including mouth and gum inflammation, respiratory infections, skin problems, eye infections, blood disorders, stomach upsets and cancers. They’re likely to lose weight and could also develop neurological and behavioural disorders.

If you suspect your pet might have FIV – for example, if they’ve recently been bitten in a cat fight and are showing early symptoms – keep them indoors, away from other cats, and contact your vet. FIV is diagnosed through a simple antibody test. If your pet tests positive, you must have any other cats they regularly have contact with tested as well.

FIV is most common in unneutered tom cats who fight rivals. It tends to be spread through bite wounds that introduce an infected cat’s saliva into another cat’s bloodstream. The virus may also be spread through sexual contact, although this is less common.

Pregnant FIV-positive cats can pass the virus on to their kittens in the womb, during birth or through their milk but, remarkably, the majority of kittens aren’t affected. Only around a third of kittens born to FIV-positive mothers develop the condition themselves.

The FIV virus cannot survive for long outside the body. This means FIV transmission is extremely unlikely through cats grooming one another, sharing food bowls or even using the same litter tray (although owners of an FIV-positive cat should take every possible measure to prevent transmission).

Rest assured that FIV cannot pass from cats to humans or other animal species. Cats also can’t get FIV from HIV-positive people.

And don’t worry about stroking an FIV-positive cat – there’s no risk of transferring the virus to other cats, pets or people via your hands.

Sadly, there’s no cure for FIV, but many infected cats live a happy and healthy life for years before their immune system becomes compromised by the virus. If an FIV-positive cat does become ill with a secondary infection, it’s vital they see a vet straight away to get appropriate treatment for that condition

In the main, you look after an FIV-positive cat just as you would look after any other pet cat! Cat welfare organisations recommend keeping FIV-positive cats indoors, or only letting them outside in a secure enclosure, to minimise their risk of infecting other cats. If you adopt an FIV-positive cat, your rescue centre and vet will give you advice on caring for them.

A few common-sense measures will help protect your FIV-positive cat’s immune system and reduce their risk of contracting secondary infections. Ensure your pet is neutered and fully vaccinated, control parasites, prevent contact with other cats or vermin, provide a nutritious diet and take them to the vet for check-ups at least twice a year.

Some catteries will take cats who are FIV-positive, provided they have no symptoms. Bear in mind, however, that staying in a cattery could increase their chance of catching a secondary infection.

One study found that cats with FIV typically live for five years after diagnosis. Another concluded, however, that an FIV-positive cat is more likely to die of other causes – such as old age or being run over – than any illness linked to their condition.

If you adopt a cat with FIV, this will usually be classed as a ‘pre-existing condition’ in your insurance policy. You won’t be able to claim for vet costs connected to the FIV, although you could claim if your cat needs unrelated treatment (for a broken leg or burn, for instance). If you have If you adopt a cat with FIV, this will usually be classed as a ‘pre-existing condition’ in your insurance policy. You won’t be able to claim for vet costs connected to the FIV, although you could claim if your cat needs unrelated treatment (for a broken leg or burn, for instance). If you have a Covered for Life® Petplan policy in place before your cat is diagnosed, then you’ll be able to claim for FIV treatment costs on your insurance. On average, Petplan receives at least 100 FIV-related claims a year.