Feline Immunodeficiency Virus

GENERAL DESCRIPTION

Feline immunodeficiency virus (FIV) is a retrovirus that infects cats throughout the United States. In the United States, 1-3% of healthy cats become infected with this virus. About 5% of FIV infected cats also have a disease called Feline Leukemia Virus. FIV is related to the HIV virus in humans however these diseases are typically species specific, meaning that HIV is spread only from human to human and FIV is spread only from cat to cat. FIV is most commonly found in outdoor cats and male cats that are 3 to 5 years old. This disease effects the immune system of infected cats, making them unable to fight off other viruses, parasites, fungi, bacteria, or other pathogens. These secondary infections often build up over time, resulting in the death of the infected cat. However, cats often live to an old age before they die of FIV or FIV-related infections or diseases.

SOURCE & CAUSE(S)

The feline immunodeficiency virus is a relatively difficult virus to pass from cat to cat. This virus cannot live outside of it’s host for more than a few hours and is easily killed by using ultraviolet light, heat, detergents, and drying. This disease is shed in saliva, and cat bites are the most common route of infection. Prolonged contact with an infected cat increases the chance that your cat will contract FIV. Mothers may infect their young in utero if they become infected with FIV during their pregnancy, as well as during nursing.

SIGNS & SYMPTOMS

• Fever
• Loss of appetite
• Poor coat condition
• Oral infections in about 50% of infected cats
• Ear infections
• Sneezing and nasal discharge
• Changes in behavior
• Enlarged lymph nodes
• Infertility or other reproductive issues
• Eye problems
• Diarrhea

Symptoms of FIV may never occur or take years to occur. Regular testing will ensure that your cat is FIV free.

DIAGNOSIS & TESTS

Diagnosis begins with a complete history and a physical exam. Your veterinarian will be most likely do the following:

• ELISA testing - This stands for "enzyme-linked immunosorbent assay" is a test used to determine if a pet has been exposed to a certain pathogen by seeing if it’s body has produced antibodies against the pathogen. It can be used to test for viruses, bacteria, microbes, or other material. In this case, the veterinarian would take a blood sample and test it for the antibodies to FIV. The ELISA test is a fast, economical test that is widely used in diagnosis of FIV. This test can likely be done in under 20 minutes at your vet clinic and is often grouped with a test for Feline Leukemia Virus. A positive test result may be confirmed by an immunofluorescence or western blot test, though your veterinarian may wait 6 months to perform another ELISA before recommending these tests. False positives may occur due to the killed virus being present in a vaccinated cat’s blood.
• Immunofluorescence - This is a technique used to illuminate either viruses or their antibodies in a tissue or culture using a fluorescent dye. It is typically used to confirm a positive ELISA test. In this case, your veterinarian will make expose your pet’s white blood cells to the feline leukemia antigen. The virus will attach to any cell displayed in the sample and show under a microscope as a bright green spot on the slide. If your cat tests positive in this test, it means he is shedding virus and is infective to other cats. This test usually has to be analyzed at an outside veterinary lab, and may take 1-2 days to return results.

TREATMENT & MANAGEMENT

Drugs similar to those used in the treatment of human AIDS can benefit cats infected with FIV, though some drugs are more toxic to cats than they are to humans.  Treatments include the use of AZT, a common human AIDS drug; alpha interferon, a drug which reduces viral replication and assists in symptom relief; and bone marrow transplantation, which replenishes lost white blood cells can help your FIV infected cat. There are also experimental drugs in the works that seem promising. Other treatments your veterinarian may use are dependent on the symptoms your cat is showing. Intravenous fluids, antibiotics, and maintaining a stress-free, healthy environment can help your cat avoid secondary infections and live a happy life.

PREVENTION & HELPFUL TIPS

Feline immunodeficiency virus can be prevented by:

• Preventing your indoor-outdoor cats from roaming or fighting with other cats
• Neuter male cats to reduce incidence of fighting
• Test all cats in a multi-cat household and test strays and new cats before introducing them to your home
• Do not let kittens feed from an infected mother cat
• There are vaccines available, but discuss with your veterinarian before vaccinating (vaccinated cats will likely test positive for the disease)