There are a few diseases that every cat owner has heard of and has been warned against at veterinary appointments. Most of these have vaccines to protect kitties—feline herpesvirus and rabies to name a few. But one severe virus, feline immunodeficiency virus (FIV), does not have a vaccine and has the potential to cause lasting damage in unprotected cats.

What is FIV?

FIV is a dangerous retrovirus. This means it inserts copies of its genetic material into the DNA of your cat’s cells, allowing it to duplicate. Unfortunately, once this occurs, it’s not possible for the body to get rid of the virus completely.

FIV acts similarly to a widely known human disease called HIV. Just like HIV, over time, FIV can cause acquired immunodeficiency disease in cats because it erodes the immune system by taking over white blood cells. What this means is that your cat’s body is unable to produce a normal immune response to fight infection and illness, leaving them much more susceptible to disease.

One of the most dangerous parts about FIV is that it does not usually present symptoms right after your cat is infected. The virus replicates slowly within the body, gradually taking over more and more cells with its DNA. Therefore, it could take many months or more for your cat to begin exhibiting signs of illness.

If your pet does begin to appear sick, it will likely be because of a secondary infection and a lack of immune response to it. Common early symptoms include:

• Recurring gastrointestinal and respiratory illness
• Swollen lymph nodes
• Gum inflammation
• Eye disease
• Persistent diarrhea
• Recurring skin and ear infections
• Poor coat condition

More advanced stages of FIV may result in more severe symptoms, such as:

• Persistent fever
• Weight loss
• Lethargy and weakness
• Changes to vision and hearing
• Cancer

How is FIV transmitted?

FIV is spread from cat to cat through infected saliva. Most often, it’s spread through bite wounds and scratches. However, infected mothers can pass FIV to her kittens during birth.

Unless one of your domestic cats is positive for FIV, it is unlikely that they will contract FIV if they stay indoors. The risk is much higher if you allow your cat to roam outside unsupervised, since they could get into an altercation with an FIV-positive feral cat.

There is no vaccine for FIV. A vaccine was available for some time, but its use has largely been discontinued due to inefficiency.

The best ways to protect your cat from contracting FIV are to test all newly adopted cats for FIV before exposing them to your cats at home and to keep your cat indoors or only allow them outside when supervised. Spaying or neutering your cat can also reduce their chances of fighting to minimize the potential for infectious bites or scratches.

Can FIV be treated?

Until your cat begins showing symptoms of illness, typically on a recurring basis, there isn’t an easy to way to tell that they have been infected with FIV. Years could pass from the initial infection before symptoms emerge.

Once FIV is suspected, your vet will need to run a few tests to identify the presence of FIV in the blood. If your cat is positive, a thorough examination is usually to follow to establish a baseline for your pet’s health and to determine any current health problems your cat may be experiencing.

Unfortunately, there is no cure for FIV. Once your cat has it, they have it for life. A life-long management plan will need to be put into place to ensure your cat’s health and happiness.

Many cats go on to live long lives in spite of an FIV diagnosis. However, even mild infections and diseases can be extremely dangerous for immunodeficient cats. You will need to monitor your pet at home over time and take them for more frequent veterinary exams to ensure they remain as healthy as possible.

Heightened preventative care can ensure the health and happiness of FIV-positive cats for many years. Because even everyday bacteria and viruses can turn dangerous for cats with FIV, it’s important to protect the cat from parasites, potential infections from other cats, dental disease and more. A nutritious diet, stress reduction and indoor lifestyle are the best courses of action.

By taking good care of your cat’s health, they can go on to live a happy life in spite of their FIV diagnosis. However, if they appear to get sick, you’ll want to take them to the vet right away for treatment, since their immune system may not be able to fight illness on its own.