Myths and Facts about FIV (Feline Immunodeficiency Virus)

There are many misconceptions and myths about FIV (Feline Immunodeficiency Virus) in felines.  It is often mixed up with FELV (FEline Leukemia Virus), because the test that is done to determine, called a Combo Test, looks for both diseases together.  FELV is a very serious, and often fatal, disease.  FIV, however, is not.  Here are some real facts and accurate information about FIV for potential adopters.  I would not hesitate to adopt a cat with FIV. 

FIV is only contagious among cats and difficult to transmit. It is also slow-acting, so cats generally do not show any symptoms until years after being infected. The amount of time it takes for the virus to make a cat become immune compromised can vary, but once symptomatic, FIV positive cats are more vulnerable to contracting other diseases. However, with the proper care, FIV positive cats can live healthy, happy lives.

The virus is primarily transmitted through bite wounds, and it can also be spread through blood. Although any feline is susceptible, un-neutered, outdoor males have the highest risk of being infected because of their propensity to fight. FIV is not usually transmitted through mating. Dr. Woyma explains, “Unlike HIV, it [FIV] is not typically spread through sexual contact and also very rarely transmitted from a mother cat to her kittens.” FIV is also rarely transmitted through casual contact, like sharing food bowls and litter boxes, social grooming, and sneezing. The unlikelihood of transmission, however, does not mean transmission isn’t possible and pet owners should always err on the side of caution.

It is extremely important to keep an FIV positive cat indoors. This not only decreases their exposure to secondary diseases, it also prevents them from spreading the disease to the rest of the feline population. Having your cat spayed or neutered is another important consideration in preventing the spread of disease, since altered animals are less likely to fight.

Feline Immunodeficiency Virus (FIV) has been associated with cats for many years, although it was only labeled as such as recently as 1986. The virus depletes the number of white blood cells, which eventually makes the cat less able to fight off infection. However, because it is such a slowacting virus many FIV positive cats can enjoy a normal lifespan with no apparent health problems resulting from the virus. FIV is species specific. It can only be transmitted from cat to cat, not to humans or other animals.

FIV belongs to the same group as Human Immunodeficiency Virus (HIV) and for this reason has received much greater attention than it would otherwise have done. The mere mention of FIV, and the fact that it is sometimes inaccurately known as 'Feline Aids', strikes unnecessary terror into the heart of many cat-owners, so it is worth taking time to consider the facts dispassionately. Firstly, the viral strains used in laboratories on experimental cats were very virulent, and much previously published information is based on this. However, FIV strains in cats living normal lives tend to be much more benign, and may never cause disease.

The virus is present in the blood and saliva of infected cats. But, like HIV, it is a very 'fragile' virus, and cannot survive for long outside the body. It also requires a high dose to establish an infection in another cat. Therefore, it is not easily passed from cat to cat. The main route of infection is through biting, when the virus in the saliva of an infected cat is injected directly into the blood stream of the cat it bites. Conversely, a cat which bites an infected cat, is a less risk of being infected, as the virus would not be injected straight into the blood stream, although there is still an element of risk. 

Cats who fight are most likely to be infected. Cat fights are most likely between entire toms and these are therefore the group most at risk. Since many feral cats are not neutered and have to compete for food, there is a higher incidence of FIV in feral cats. The take-home message is to prevent fighting - make sure your cat is neutered! Transmission between cats in a group who do not fight is unlikely as the virus can only survive a very brief time outside a cat's body, and it cannot be transmitted indirectly, such as on food, feeding equipment, clothes, shoes, hands etc. (unlike the situation with feline leukaemia). Recent research suggests the likelihood of cats passing on FIV to others in the same household is as low as 1-2%.  Thus it is considered safe for FIV and non FIV cats to live together in a home.

It has not been proved that the virus is transmitted sexually, although often the tom cat will hold onto the scruff of the female's neck with his teeth, so if the skin is punctured at that point, transmission is possible.

A cat who contracts FIV will usually still have a strong immune system for several years after infection, it is only over time, that the effects of the virus may start to show, and even then, most infections can be treated with the appropriate medications. With love and good care however, many FIV+ cats can live normal lifespans. These days, it's not unusual to find FIV+ cats reaching 15 years or more. Knowing what we now do of the prolonged nature of the condition, euthanasia is totally inappropriate and inhumane.

A healthy FIV positive cat can live for many years, and indeed can often outlive non-infected cats, but please be aware that this is not always the case. Due to their impaired immune system, the cat may succumb to illness earlier, and not reach their normal life expectancy. FIV cats will need prompt veterinary assistance for even minor symptoms. With good care however, many FIV+ .cats can live normal life spans. These days, it's not unusual to find FIV+ cats reaching 5 years or more.

More information on FIV can be found here: Cornell University College of Veterinary Medicine