What is FIV and FeLV? | How is FIV and FeLV spread? | How will I know if my cat has FIV or FeLV? | How do you treat a cat with FIV or FeLV? | How can I prevent my cat from contracting FIV or FeLV? | Can people become infected with FIV or FeLV?
WHAT IS FIV AND FeLV?
FIV and FeLV belong to a family of viruses called retroviruses. All retroviruses (including the Human Immunodeficiency Virus) produce an enzyme which allows them to insert a part of their own genetic material into that of the cells they have infected. Although the FIV and FeLV are related, they are different from one another in shape, genetic makeup and the way in which they cause disease. Cats infected with FIV and FeLV can be asymptomatic for many years; hence many owners will not even realise their cats have either virus as they may show no signs of being ill.
HOW IS FIV AND FeLV SPREAD?
Both FIV and FeLV are shed in high quantities in the saliva. There are slight differences in the way in which the two viruses are transmitted:
FIV is transmitted primarily through biting, as occurs during territorial fights. Transmission through intimate contact can occur but is unlikely, hence one cat in a multi-cat household may test positive for FIV while the rest remain negative for the virus. Infected queens may pass the virus on to her kittens in utero (in the uterus) and through infected milk.
FeLV may be transmitted through a bite wound, but more likely through mutual grooming, shared litter boxes and feeding dishes. As with FIV, infected queens can also transmit the FeLV virus to her live and unborn kittens. FeLV is easily transmitted between cats in a multi-cat household.
HOW WILL I KNOW IF MY CAT HAS FIV OR FeLV?
FIV and FeLV infect the white blood cells of cats causing an immune deficiency. This state of immune deficiency will result in your cat being vulnerable to any number of secondary viral, bacterial and fungal infections. Cats infected with either virus may have recurrent illness interspersed with periods of relative health. Cats with FIV or FeLV usually have a slow recovery period and may succumb to chronic infections. Cats infected with FIV have an increased risk of developing cancer such as lymphoma. Signs of illness will also vary with the stage of the disease. In the initial infection stage cats may have a fever and enlarged lymph nodes.
Later stages of the disease may show the following symptoms:
- Loss of appetite
- Slow, progressive weight loss
- Poor coat condition
- Enlarged lymph nodes
- Persistent fever
- Pale gums
- Mouth infections
- Infections of the skin, bladder and respiratory tract
- Persistent diarrhoea

HOW DO YOU TREAT A CAT WITH FIV OR FeLV?
Unfortunately, there is no cure for either FIV or FeLV. Treatment is aimed at keeping your cat free of secondary diseases and treating them appropriately as they occur. Ensure your cat has a healthy immune system by feeding a balanced and nutritious food, scheduling routine visits with your vet and closely monitoring the health of your cat. Should you notice any change in his/her health, alert your veterinarian about these changes immediately. Anti-viral therapy used routinely for patients with HIV is not routinely used in cats as some of these drugs are toxic to cats and are very expensive. Immune modulator therapy such as interferon can be used to try and improve the immune system of infected cats.
HOW CAN I PREVENT MY CAT FROM CONTRACTING FIV OR FeLV?
Owners can prevent their cats from being exposed to either virus by preventing their cats from roaming. Neutering of male cats decreases roaming as well as territorial fighting which aids the transmission of these viruses. Cats can be vaccinated against FeLV. This is usually advocated in townhouse complexes where cats come into close contact with one another.
CAN PEOPLE BECOME INFECTED WITH FIV OR FeLV?
Although FIV, FeLV and HIV belong to the same family of viruses they are very different. Both FIV and FeLV are feline specific viruses which do not infect humans.
Reference: Bayer HealthCare