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Cat FIV (Feline Immunodeficiency Virus)

Cats who are infected with feline immunodeficiency virus (FIV) may not show symptoms until years after the initial infection occurred. Although the virus is slow-acting, a cat's immune system is severely weakened once the disease takes hold. This makes the cat susceptible to various secondary infections. Infected cats who receive supportive medical care and are kept in a stress-free, indoor environment can live relatively comfortable lives for months to years before the disease reaches its chronic stages.

Many people confuse FIV with feline leukemia virus (FeLV). Although these diseases are in the same retrovirus family and cause many similar secondary conditions FeLV and FIV are different diseases.

What Are the Symptoms of FIV?

An FIV-infected cat may not show any symptoms for years. Once symptoms do develop, however, they may continually progress -or a cat may show signs of sickness interspersed with health for years. If your cat is demonstrating any of the following symptoms, please have examined by your veterinarian:

  • Enlarged lymph nodes
  • Fever
  • Anemia
  • Weight loss
  • Disheveled coat
  • Poor appetite
  • Diarrhea
  • Abnormal appearance or inflammation of the eye (conjunctivitis)
  • Inflammation of the gums (gingivitis)
  • Inflammation of the mouth (stomatitis)
  • Dental disease
  • Skin redness or hair loss
  • Wounds that don't heal
  • Sneezing
  • Discharge from eyes or nose
  • Frequent urination, straining to urinate or urinating outside of litter box
  • Behavior change

How Is FIV Transmitted?

FIV is mainly passed from cat to cat through deep bite wounds, the kind that usually occur outdoors during aggressive fights and territorial disputes-the perfect reason to keep your cat inside.

Another, less common mode of transmission is from an FIV-infected mother cat to her kitten. FIV does not seem to be commonly spread through sharing food bowls and litter boxes, social grooming, sneezing and other casual modes of contact.

Which Cats Are Most Prone to FIV?

Although any feline is susceptible, free-roaming, outdoor intact male cats who fight most frequently contract the disease. Cats who live indoors are the least likely to be infected.