What Is FIV in Cats: Understanding Feline Immunodeficiency Virus

As devoted cat owners, we cherish the companionship and love that our feline friends bring into our lives. Our duty to care for them goes beyond providing food and shelter; it extends to safeguarding their health and well-being. Unfortunately, just like humans, cats are also susceptible to various health conditions, one of which is FIV, or Feline Immunodeficiency Virus.

As we embark on this journey to comprehend what FIV in cats truly entails, we aim to equip ourselves with knowledge and understanding to better care for our furry companions.

In this article, we will delve into the ins and outs of Feline Immunodeficiency Virus, shedding light on its causes, symptoms, and available treatments. We’ll debunk common misconceptions and provide practical tips to protect our beloved cats from this silent threat.

Join us as we unravel the mysteries surrounding FIV in cats and empower ourselves to make informed decisions about our feline friends’ health. Let’s embark on this informative quest to ensure a brighter, healthier future for our purring pals.

What Is FIV in Cats?

If you are a cat lover, you may have heard of FIV, or feline immunodeficiency virus. FIV is a viral infection that affects the immune system of cats, making them more susceptible to various diseases and infections.

FIV is often compared to HIV, or human immunodeficiency virus, in humans, because they have similar effects on the body.

However, FIV is not contagious to humans or other animals, and can only be transmitted between cats through deep bite wounds or from mother to kitten.

According to the Cornell Feline Health Center, “approximately 2.5-5% of healthy cats in North America are infected with FIV, and the rate is higher (15% or more) in cats that are sick or at high risk of infection.”

Outdoor cats, especially un-neutered males who tend to fight with other cats, are at the greatest risk of contracting FIV.

FIV is a chronic and progressive disease that can affect cats of any age, breed, or gender. However, FIV symptoms may not appear for months or years after infection, and some cats may never show any signs of illness. FIV symptoms can also vary depending on the stage and severity of the disease, and may include:

• Poor coat condition
• Fever that keeps coming back
• Lack of appetite
• Inflammation in the mouth and gums
• Chronic or recurrent infections in the eyes, skin, upper respiratory tract, or bladder
• Constant diarrhea
• Persistent eye problems
• Seizures
• Behavioral changes
• Neurological disorders
• Slow and steady weight loss
• Cancer
• Blood disease

Because FIV symptoms are often vague and nonspecific, they can be easily confused with other conditions or diseases in cats. Therefore, it is important to have your cat tested for FIV if they show any signs of illness or if they have been exposed to a potential source of infection. Testing for FIV can also help you provide the best care and management for your cat if they are infected.

What Are the Symptoms of FIV in Cats?

FIV can have different stages and symptoms depending on how long the cat has been infected and how well their immune system is coping. Some cats may not show any signs of illness for months or years after being infected, while others may develop chronic or recurrent infections that affect various parts of the body.

The first stage of FIV infection is called the acute phase. This usually occurs 1-3 months after exposure to the virus and lasts for a few weeks. During this time, the virus is multiplying rapidly in the lymph nodes and spreading throughout the body.

The cat may experience fever, lethargy, loss of appetite, swollen lymph nodes and inflammation of the mouth and gums. However, these symptoms are often mild and transient, and may go unnoticed by the owner or attributed to other causes.

The second stage of FIV infection is called the asymptomatic phase or latent phase. This can last for months or years after the acute phase and is characterized by a lack of obvious symptoms.

The cat may appear healthy and normal during this time, but the virus is still present in their body and slowly damaging their immune system. The cat may have occasional bouts of illness or infection that resolve with treatment, but they are not yet severely immunocompromised.

The third stage of FIV infection is called the progressive phase or terminal phase. This occurs when the cat’s immune system is severely weakened by the virus and can no longer fight off other infections and diseases. The cat may develop various symptoms and complications that affect different organs and systems of their body, such as:

• Poor coat condition
• Weight loss
• Anemia
• Inflammation of the mouth and gums (gingivitis and stomatitis)
• Eye problems (conjunctivitis, uveitis, glaucoma)
• Skin problems (abscesses, ulcers, fungal infections)
• Respiratory problems (sneezing, nasal discharge, pneumonia)
• Urinary problems (cystitis, urethral obstruction)
• Diarrhea
• Seizures
• Behavior changes (aggression, depression)
• Neurological problems (ataxia, dementia)

Some cats with FIV may also develop cancers^[1] or blood disorders as a result of their weakened immune system. The most common types of cancer associated with FIV are lymphoma and leukemia, which affect the lymph nodes and blood cells respectively.

“Cats of any age can develop lymphoma, although most affected animals are 10 to 12 years of age.  Unvaccinated outdoor cats are at greater risk than indoor cats due to their greater exposure to FeLV infection”, according to Cornell Feline Health Center.

Other types of cancer that may occur in FIV-positive cats are squamous cell carcinoma^[2], which affects the skin and mouth, and mammary gland tumors, which affect the breast tissue.

The symptoms and complications of FIV in cats can vary widely depending on the individual cat, the strain of the virus, the co-infection with other diseases, and the environmental factors. Some cats may have mild or no symptoms for a long time, while others may have severe or fatal symptoms in a short time.

The average life expectancy of FIV-positive cats is about 5 years after diagnosis, but some may live longer or shorter depending on their condition.

Diagnosis of FIV in Cats

The diagnosis of FIV in cats is based on blood tests that detect antibodies to the virus. Antibodies are proteins produced by the immune system to fight off foreign invaders, such as viruses or bacteria.

However, antibodies do not necessarily mean that the cat is currently infected with FIV, as they can also indicate past exposure or vaccination.

“A cat bitten by another with an unknown medical history should be tested for FIV approximately two months after the bite” suggests, Malcolm Weir, DVM, VCA Hospitals.

There are different types of blood tests available for FIV diagnosis, such as:

• ELISA (enzyme-linked immunosorbent assay): This is a simple and quick test that can be performed in a veterinary clinic or laboratory. It uses a small sample of blood from the cat’s ear or leg and a special device that changes color if antibodies are present. However, this test can sometimes give false positive results, especially in kittens who may have inherited antibodies from their mother or in cats who have been vaccinated against FIV.

• Western blot: This is a more accurate and reliable test that can confirm or rule out an ELISA result. It uses a larger sample of blood from the cat’s vein and a special gel that separates the antibodies by size and shape. A positive result means that the cat has been exposed to FIV at some point in their life.

• PCR (polymerase chain reaction): This is a newer and more sensitive test that can detect the genetic material of the virus itself. It uses a small sample of blood from the cat’s vein and a special machine that amplifies and identifies the DNA or RNA of the virus. A positive result means that the cat is currently infected with FIV.

However, none of these tests are perfect or foolproof. They can sometimes give false negative results, especially in cats who have been recently infected but have not yet developed antibodies or in cats who have advanced disease and have lost their ability to produce antibodies. They can also cross-react with other viruses or vaccines that may cause similar symptoms in cats.

Therefore, it is important to interpret the test results carefully and consider other factors such as:

• The cat’s age, health status, history, and risk factors
• The type and quality of the test used
• The possibility of retesting at a later time or using a different test

It is also important to consult with your veterinarian regularly and monitor your cat’s health closely if they are suspected or confirmed to have FIV.

How Is FIV in Cats Treated?

There is no cure for FIV in cats, but there are ways to manage the condition and improve the quality of life of infected cats. The main goals of treatment are to support the cat’s immune system, prevent or treat secondary infections and complications, and relieve any pain or discomfort.

Some of the treatment options for FIV in cats are:

• Keeping the cat indoors to prevent exposure to other infections and injuries. Indoor cats have a lower risk of contracting other diseases and a longer life span than outdoor cats.

• Providing a balanced diet and fresh water to maintain good nutrition and hydration. A high-quality commercial cat food that meets the cat’s nutritional needs is recommended. Some veterinarians may also prescribe supplements or special diets for cats with specific conditions, such as kidney disease or diabetes.

• Giving regular parasite prevention and vaccinations to prevent other diseases. Parasites such as fleas, ticks, worms and mites can cause skin problems, anemia and infections in cats. Vaccinations can protect cats from diseases such as rabies, feline leukemia virus (FeLV), feline panleukopenia (FPV), feline calicivirus (FCV) and feline herpesvirus (FHV). However, some vaccinations may not be effective or safe for FIV-positive cats, so they should be discussed with the veterinarian before administration.

• Monitoring the cat’s health and weight regularly and reporting any changes to the veterinarian. A regular physical examination and blood test can help detect any signs of illness or infection early and provide appropriate treatment. Weight loss can indicate malnutrition, dehydration or disease in cats

• Treating any secondary infections or complications promptly with antibiotics, anti-inflammatories or other medications as prescribed by the veterinarian. Secondary infections can be bacterial, viral, fungal or protozoal in nature and can affect various parts of the body.
  
  Anti-inflammatories can help reduce pain and inflammation in cats with arthritis or stomatitis. Other medications may be used to treat specific conditions, such as steroids for allergies or asthma, anticonvulsants for seizures or antidepressants for behavior problems.

• Antiviral drugs such as AZT (zidovudine) or Tenofovir (tenofovir disoproxil fumarate) can inhibit the replication of the virus and reduce the viral load in the blood. However, these drugs are not widely available, expensive and may have side effects such as anemia, nausea or liver toxicity. They should be used with caution and under the supervision of a veterinarian.

• Immune modulators such as interferon or L-lysine can stimulate the immune system and enhance its ability to fight off infections. However, these drugs are not proven to be effective or safe for FIV-positive cats, and they may have side effects such as fever, lethargy or allergic reactions. They should be used with caution and under the supervision of a veterinarian.

How Can FIV in Cats Be Prevented?

The best way to prevent FIV in cats is to avoid contact with infected cats or potential sources of infection. Some of the prevention measures

for FIV in cats are:

• Spaying or neutering cats to reduce their tendency to roam and fight. Spayed or neutered cats are less likely to engage in territorial or sexual behaviors that may lead to bite wounds and transmission of FIV. They also have other health benefits, such as reduced risk of mammary gland tumors or uterine infections.

• Keeping cats indoors or supervised when outdoors to prevent encounters with stray or feral cats. Indoor cats have a lower risk of contracting FIV and other diseases than outdoor cats. If outdoor access is necessary, it should be limited and supervised to avoid contact with unknown cats. Alternatively, a secure enclosure or a harness and leash can be used to provide safe outdoor access for cats.

• Testing new cats for FIV before introducing them to other cats in the household. New cats should be tested for FIV before they are allowed to mingle with other cats in the home. This can prevent the spread of FIV among the resident cats and allow appropriate care and isolation for the infected cat. Testing should be done at least 8 weeks after exposure to ensure accurate results.

• Separating infected cats from uninfected cats to prevent transmission through bite wounds. Infected cats should be kept in a separate room or area from uninfected cats to avoid contact and fighting. They should have their own food bowls, water bowls, litter boxes and toys to prevent sharing of saliva or blood. They should also receive regular veterinary care and monitoring to maintain their health and well-being.

There is also a vaccine available for FIV in some countries, but it is not widely recommended because it has some limitations and drawbacks, such as:

• It does not protect against all strains of FIV. The vaccine only covers a few subtypes of FIV that are prevalent in certain regions, but not others. It may not provide adequate protection for cats that are exposed to different strains of FIV.

• It may interfere with the accuracy of the antibody test for FIV diagnosis. The vaccine stimulates the production of antibodies to FIV, which may cause false positive results on the antibody test. This can make it difficult to distinguish between vaccinated and infected cats, and may lead to unnecessary euthanasia or isolation of healthy cats.

• It may cause adverse reactions or side effects in some cats. The vaccine may cause local reactions at the injection site, such as swelling, pain or abscesses. It may also cause systemic reactions, such as fever, lethargy or allergic reactions. In rare cases, it may induce a type of cancer called injection site sarcoma, which is a malignant tumor that develops at the site of vaccination.

Therefore, it is important to discuss with your veterinarian whether the vaccine is suitable for your cat and weigh the benefits and risks carefully. The vaccine should only be given to healthy cats that are at high risk of exposure to FIV, such as outdoor cats or those who live in areas where FIV is prevalent. The vaccine should also be accompanied by a microchip or a tattoo that identifies the cat as vaccinated.

FAQ

Well, That’s a Wrap

FIV in cats is a serious but manageable condition that affects the immune system of cats. It can cause various symptoms and complications that may affect the cat’s health and well-being. FIV can be diagnosed by a blood test, but it may require confirmation by a veterinarian.

FIV can be treated by supportive care, medications and regular monitoring, but there is no cure. FIV can be prevented by avoiding contact with infected cats or potential sources of infection, and by considering vaccination in some cases. FIV-positive cats can still live long and happy lives with proper care and attention.

Reference:

1. Blackwood, L. (2013, April 19). Cats with Cancer. Journal of Feline Medicine and Surgery. Retrieved July 31, 2023, from Sage Journals
2. Dickinson, K. (2022). Squamous cell carcinomas in cats. PetMD.