Information about the Kentucky State University Cooperative Extension Program 2021

Dr. Jerusha (Jessie) Lay, Assistant Professor of Animal Health

Feline Leukemia Virus and Feline Immunodeficiency Virus are both viruses that are contagious between cats that have, at this time, no cure. These viruses are most commonly transmitted between cats through cats fighting, although feline leukemia can also be transmitted through close contact. Cats are solitary hunters and are territorial in the wild (especially males), which lends this disease to be more common in populations of feral cats and cats that live or spend much time outdoors. Infected mothers may also transmit to her kittens. All newly acquired cats should be tested. Vaccines are available and may be recommended by a cat owner's veterinarian depending on risk factors, such as indoor versus outdoor or exposure to other cats.

Feline Immunodeficiency Virus is NOT contiguous to humans but does act similarly in cats as the Human Immunodeficiency Virus acts in people. The virus causes a weakened immune system, which makes infected cats more susceptible to all other infections. Infected cats may appear healthy and show no symptoms; it may be years before they succumb to another disease. The primary transmission or way cats become infected is through bite wounds. As cats, especially male cats, are territorial, fighting promotes the spread of the virus. There is no cure or treatment once a cat is infected. A vaccination is available but not effective for all cats and not considered a core vaccine. The best prevention is to avoid bite wounds. This is much easier when cats are strictly indoors versus outdoor or feral cats.

FIV causes the immune system to be suppressed and not fight off diseases as it should. This causes infected cats to be affected more often and more severely to other viruses, bacteria or fungus. These cats may have long periods of health and intermittent periods of illness. Some symptoms may include recurrent infections of the mouth, eyes or bladder, and occasionally persistent diarrhea.

periods of health and intermittent periods of illness. Some symptoms may include recurrent infections of the mouth, eyes or bladder, and occasionally persistent diarrhea.

Feline Leukemia Virus may also be transmitted through bite wounds; however, it is much more contagious because it is also shed through mutual grooming, sharing water or food bowls or sharing litter boxes, or from an infected mother to her kittens. Feline Leukemia Virus is also the most common cause of cancer in cats. Unlike FIV, the leukemia virus itself does cause disease; however, it may be years between infection and clinical symptoms. In the late stages of disease, cats may show progressive or reoccurring weight loss, poor appetite, fever, poor hair coat, enlarged lymph nodes, pale gums/anemia, severe inflammation of the mouth or eye conditions, respiratory infections, or other infections. Most infected kittens/cats will only live a few years after diagnosis.

Your local veterinarian will likely recommend FIV/Feluk testing of any newly acquired cats.