What Is Feline Immunodeficiency Virus (FIV)?
By Dr. Amanda Page
What is Feline Immunodeficiency Virus?
Feline Immunodeficiency Virus (FIV), also known as Feline AIDS, is a serious viral disease that affects ONLY CATS. Fortunately, there are many ways we can protect our cats from exposure to this disease. It is estimated that 3.5% of cats in the western United States are infected with FIV.
How does FIV cause disease?
FIV causes suppression of the immune system by attacking important cells of the cat’s immune system which protect the cat from common infectious agents (bacteria, viruses, etc). Many of the infectious agents are found in the everyday environment but don’t cause disease in healthy cats. However if a cat’s immune system is weakened, as with FIV, these same organisms can cause disease – known as secondary or opportunistic infection. The disease is comparable to the human HIV but ONLY AFFECTS CATS. However, it is recommended that immunocompromised people (i.e. chemo patients and human AIDS patients) not reside with FIV + cats because these cats are more likely to harbor opportunistic infections that could be transmitted to immunocompromised humans.
What is the outcome of disease?
The acute phase of disease is the period following initial infection. The acute (beginning) phase of the disease may last days to weeks and the cat may have a fever, be depressed, have diarrhea or vomiting, inflamed mouth, or swollen lymph nodes. However, many owners may not notice this phase of disease. Following the acute phase, the cat usually enters an asymptomatic phase where the cat is free of signs of disease and lives a healthy life for 6-10 years. Some cats will never develop the terminal / acquired immune deficiency (AIDS) phase but some will. If the cat’s disease progresses into this AIDS phase, the immune system cannot fight off bacteria, virus, or fungi that won’t affect normal cats, and the cat can become very ill and not recover. Infection is for life but it is important to remember many cats with FIV can live a happy, healthy life for many years. FIV positive cats must be kept indoors only, have good nutrition, avoid raw diets, be provided with low stress environments and need regular visits to the veterinarian.
How does a cat get FIV?
The most common way cats get the disease is through bite wounds from an infected cat. Cats who are most commonly infected with FIV are intact (not neutered) male cats that are allowed outdoors; this is because intact animals tend to roam and get into fights with other cats. On rare occasions the virus can be transmitted from mother to kittens. Sexual transmission is unusual although the semen of infected cats frequently contains the virus. Cats living together are unlikely to contract the virus from casual contact provided the cats get along and do not fight.
How do we test for FIV?
A simple in-house blood test can be performed to test for FIV. If the test is positive it could mean that the cat has FIV, the cat has been vaccinated for FIV, or the cat is a kitten and should be retested. A positive test should be confirmed by a Western Blot. If the test is negative it could mean that the cat is not infected with FIV or the cat was recently infected (up to 60 days ago) but won’t test positive yet.
How can we protect our cats from FIV?
- Keep cats exclusively INDOORS
- SPAY & NEUTER (reduces urge to roam and fight)
- ISOLATE & TEST NEW CATS for FIV before allowing them to interact with your existing pets
- A VACCINE is available BUT only protects against some subtypes of the virus and will cause the cat to test positive for FIV on the blood test. If a cat is vaccinated for FIV it should have a microchip that is linked to information stating the cat was vaccinated for FIV.
Read Part 1 of the Truth About FeLV/FIV Testing – Feline Leukemia Virus
