FeLV vs. FIV

By: Talin Seta Shahinian

You may have heard of the terms FeLV and FIV, but don’t know exactly what they are or the difference between them. They’re two different ailments that affect around 2 to 4% of the cat population of America. FeLV stands for feline leukemia virus, and FIV is short for feline immunodeficiency virus. Although they may be confused for each other, they’re two separate conditions with different symptoms and characteristics.

What Is FeLV?

FeLV is an infection caused by the feline leukemia virus, a retrovirus that becomes part of their DNA once in the cat’s system. It’s transmitted between cats by saliva, nasal secretions, urine, feces, and milk. A FeLV mother can pass it to her kittens through milk, or grooming them. It can also be transmitted by cats biting one another.

Symptoms and Diagnosis of FeLV

FeLV breaks down the cat’s immune system, leading to poor coat condition, weight loss, pale gums, yellowing within the mouth, and the whites of the eyes. However, FeLV can be tricky, as cats can present with differing symptoms, and some cats can be asymptomatic. Blood tests are necessary to detect the presence of the virus, whether the cat is presenting with symptoms or not.

Transmission of FeLV

Even without displaying any clinical symptoms, a FeLV cat can transmit the virus to another cat. FeLV can be transmitted by grooming and via shared food or water bowls. For this reason, a FeLV cat should only live with other FeLV cats. They can also live with FeLV-vaccinated cats, but there’s always some level of risk, even with vaccines. FeLV can’t be transmitted to humans or other animal species. So dogs, birds, reptiles, and other pets will be perfectly safe with a FeLV cat in the household.

The FeLV and Cancer Connection

In some cats, the virus can go dormant, and not present symptoms, and in other cases, it can cause fever, infections, blood disorders, and cancer. There’s a connection between leukemia, or lymphoma, a cancer of the white blood cells, and the feline leukemia virus, but not all FeLV infections end up causing cancer, and not all cats with these forms of cancer have FeLV.

Treatment and Prevention of FeLV

There’s no treatment for FeLV, but FeLV cats can live and have an average life span. However, the best way to deal with FeLV is to prevent your cat from getting it in the first place. Younger cats are the most susceptible and should be vaccinated against FeLV. If you choose to adopt a FeLV cat, or your cat gets FeLV after adoption, make sure to keep up with regular veterinary care every six months to stay on top of any symptoms, giving them the best chance of sharing a long life with you.

What Is FIV?

Feline immunodeficiency virus affects a cat’s immune system, and this causes inflammation, which can lead to some of the following symptoms:

  • Fever.
  • Wounds that don’t heal.
  • Poor appetite and weight loss.
  • Enlarged lymph nodes.
  • Diarrhea.
  • Anemia.
  • Inflammation of the gums (gingivitis).
  • Inflammation of the mouth (stomatitis)
  • Redness of the skin.
  • Disheveled coat/fur loss.
  • Sneezing.
  • Eye inflammation or eye infections.
  • Eye or nasal discharge.
  • Upper respiratory infections.
  • Behavioral changes and possible seizures.
  • Urinary issues, such as urinating outside the box, straining to urinate, or increased urinary frequency.

FIV Transmission, Diagnosis, and Prognosis

One of the primary sources of viral transmission of FIV from one cat to another is by bite wounds from cats fighting with each other. It tends to affect more unneutered male cats who live outdoors or indoor/outdoor cats, as before neutering, male cats are more prone to aggressive behavior in the wild. However, it can also be passed from an FIV mother to her kittens. A blood test diagnoses FIV, and there’s no effective vaccine to prevent FIV. There’s also no treatment for FIV, but many FIV cats can still have a long life.

FIV isn’t easily spread between cats through casual contact like grooming, shared food, water bowls, or litter boxes. An FIV cat can live with an uninfected cat, and it can’t spread to humans or other animals. FIV doesn’t typically cause severe illnesses. Rather it can affect a cat’s health by leaving them open to secondary infections due to their immunocompromised status. To help them stay healthy and live a long life, take them for routine veterinary care appointments and get them treated promptly if any secondary ailments crop up between regular visits.

The Differences Between FeLV and FIV

The main difference between FeLV and FIV is that FeLV is the more serious of the two conditions and is more easily transferable. FeLV can lead to more serious medical conditions, depending on the cat. FeLV is also a more rapidly developing condition, whereas it can take years for FIV to progress. The other difference is how both diseases affect communal living with multiple cats. FeLV cats should only live with other FeLV cats, while FIV cats can live with FIV or FIV- cats. Remember, neither condition affects humans or other animals.

Adopting a FeLV or FIV Cat

While both conditions pose challenges, both FeLV and FIV cats are worthy of loving, forever homes and can be wonderful companions for many years to come. So, don’t pass over a wonderful cat due to fear and misinformation. With good veterinary care and lots of TLC, you and your special feline friend can enjoy many joyful years together.

If you live in NW Wisconsin, Purple Cat Mobile Vet Clinic is here to help you keep your cat healthy and happy. We’re a high-quality, high-volume, low-cost spay/neuter clinic. We see cats exclusively. Find information for scheduling on our www.purplecatvet.com website. You can also look on our Facebook page for more helpful information on all things feline!


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