Feline Leukemia (FeLV) and Feline Immunodeficiency Virus (FIV)

Cat owners often hear of FeLV and FIV but aren’t too sure exactly what they are and how they may affect their beloved fact. We’ve put together this blog to help explain and break down what each of these viruses are and how they can cause great damage to our pets and our lives.

Feline Leukemia Virus (FeLV) is usually transmitted through grooming and social behaviors – sharing water dishes, food bowls, litterboxes etc. Kittens become infected during either development in mom or when mom starts to groom and nurse her kittens. Saliva and nasal discharge is how this virus is transferred among cats. Cat’s often do not primarily pass away due to FeLV, but they instead acquire an infection or cold that their body cannot fight off and pass away from the infection they acquired, due to their body being unable to fight it off because of FeLV.

Feline Immunodeficiency Virus (FIV) transmission is usually associated with cats that fight over territory and roam outdoors. As the name implies, FIV is similar to the human form of HIV, where the virus primarily attacks the immune system – therefore these cats generally present to the veterinary hospital with signs not directly associated with the virus. Like FeLV, the cat typically acquires an infection or wound that will not heal which leads to the cat’s death.

Both of these feline viral diseases are preventable. While neither of which have a “cure”, cats with these diseases can live relatively normal lives until they become clinically sick and show signs of illness. Usually secondary illnesses are what “unmask” their underlying condition (you may notice your cat sneezing, you bring him or her into the veterinarian and after some blood work is done, it is learned that while your cat is sick [sneezing], the bigger issue is that he or she also suffers from FeLV or FIV).

Approximately 5% of cats can be infected with both FIV and FeLV. Cancer risks increases 6x with FIV, 60x with FeLV and 80x with FeLV and FIV infections. In the United States approximately 2 – 3% of cats are infected with the leukemia virus. Infection rates increase when cats are very young and sick, or have increased exposure to viruses. The age groups commonly affected are cats between 1 to 6 years of age with a median age of 3 years.

Prevention: keeping cats indoors is one way to prevent your cat from exposure. When introducing new cats to the household, temporary segregation is always recommended to reduce residents from becoming exposed to bacterial and viral disease present at shelters. Vaccines are also available to prevent both of these viruses to be picked up by your cat (please continue reading for more information).

Disinfection: both viruses are easily killed by household detergents and do not last in the environment.

Vaccination: Generally FeLV vaccination can be administered to kittens at 8 – 9 weeks of age with a second booster 3 – 4 weeks later. Vaccine booster is administered once yearly. A vaccine is available for FIV cats, however this particular vaccine will yield a positive result on routine testing. Therefore, young kittens that test positive are generally retested at 6 months of age.

In conclusion, these viruses are not a death sentence for your cat and you can prevent your cat from obtaining these viruses. Annual blood work, exams and indoor only cats will help your cat stay healthy, virus free and alive! If you would like to discuss your cat’s health, please schedule an appointment with Dr. Jill Christofferson, Dr. Blythe Jurewicz or Dr. Wendi Aengus today: (925) 937-5000

Caroline Li, DVM