Feline immunodeficiency virus (FIV) is a lentivirus that attacks a cat’s immune system much like HIV does in humans. However, FIV only infects cats it isn’t transmissible to people or dogs. The virus slowly weakens the immune response, making infected cats prone to secondary infections and illnesses. According to the RSPCA Knowledgebase, about 9-20 % of cats with outdoor access in Australia test positive for FIV, with a national average of around 15 %. Un neutered males that roam and fight are at highest risk because the virus is mainly transmitted through deep bite wounds. Indoor cats and desexed pets rarely become infected.
FIV should not be confused with the feline leukaemia virus (FeLV). FeLV spreads more easily through grooming or sharing bowls, whereas FIV requires blood-to-blood contact such as biting. Cats living with FIV can enjoy long, happy lives when provided with good nutrition, a safe environment and regular veterinary care.
How FIV Spread in Cats?
The primary route of FIV transmission is through deep bite wounds. An infected cat’s saliva enters another cat’s tissues during fights, particularly among un neutered outdoor males. Vertical transmission from a pregnant queen to her kittens can occur but is uncommon. Because casual contact doesn’t spread the virus, FIV positive cats generally can share food bowls and groom each other without infecting housemates so long as they don’t fight.
Risk Factors Include:
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Outdoor Lifestyle: roaming cats encounter unfamiliar cats and may fight over territory. Providing a stimulating indoor environment with a cat tree or perches helps keep cats entertained and reduces the desire to roam.
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Male Sex and Intact Status: males, especially un neutered toms, are more territorial and more likely to bite. Desexing your cat reduces aggression and roaming.
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Mixed Households: introducing new cats gradually and supervising interactions minimises the chance of fighting. Use a spacious Michu XXL Stella Deluxe Cat Litter Box to give each cat plenty of room to toilet comfortably.
Phases and Symptoms of FIV
FIV progresses slowly through three stages:
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Acute Phase: Shortly after infection, some cats develop transient fever, enlarged lymph nodes, lethargy or poor appetite. These signs may be mild and go unnoticed.
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Asymptomatic Phase: The virus remains in the body but may not cause symptoms for months or even years. During this stage, cats appear healthy and can live normal lives.
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Progressive or FAIDS Stage: As the immune system weakens, cats become susceptible to chronic infections, dental disease, weight loss, diarrhoea and anaemia. Mouth inflammation, recurrent respiratory infections, poor coat condition and neurological problems may occur. Secondary infections such as urinary tract disease are common. Monitoring urine pH with health monitoring tofu cat litter or health monitoring pellets can help detect early signs of bladder problems.
Because FIV signs are non specific, any chronic illness, recurrent infection or unexplained weight loss in a cat particularly one with outdoor history should prompt a veterinary examination.
Diagnosing FIV
Veterinarians diagnose FIV using blood tests that detect antibodies against the virus. A screening ELISA or SNAP test can be performed in the clinic, often with results in minutes. Positive results should be confirmed with a second test such as Western blot or PCR to rule out false positives. Kittens may carry maternal antibodies for up to six months and vaccinated cats will also test positive, so testing should be interpreted with caution and repeated if needed.
When bringing a new cat into your home, ask your veterinarian to test for FIV and isolate the newcomer until status is known. Routine testing is also advisable for cats showing clinical signs or those that have been in fights. Keeping a cat grooming kit on hand helps you notice sores, dental problems or ear infections early.
Is There a Cure for FIV?
There is no cure for FIV. The virus integrates into the host’s DNA and cannot be eliminated. Management focuses on supportive care and preventing secondary infections:
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Indoor Lifestyle: Keeping an FIV positive cat indoors protects them from pathogens and prevents transmission to other cats. Provide enrichment with interactive cat toys and climbing structures to reduce boredom.
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Nutrition: Feed a high quality diet rich in moisture to support kidney and urinary health. Consider wet cat food and ensure fresh water is always available. Balanced nutrition helps maintain weight and coat condition.
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Regular Veterinary Care: Schedule wellness exams at least twice a year. Early treatment of dental disease, skin infections or gastrointestinal issues improves outcomes. Discuss the need for bloodwork, urinalysis and dental cleanings with your vet. Our article How to Cure UTI in Cats explains how prompt veterinary care is essential when urinary infections develop.
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Parasite Prevention: Use flea, tick and worm preventatives as recommended. A compromised immune system makes cats more susceptible to parasites.
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Stress Reduction: Provide hiding spots and vertical territory (such as a sturdy cat tower) to minimise stress, which can trigger illness. Clean their litter regularly with low dust natural tofu cat litter to reduce respiratory irritation.
An FIV infected cat can live many years when cared for properly. They should not be euthanised solely based on a positive test. In fact, shelters and rescue organisations including many in Australia successfully adopt out FIV positive cats.
Vaccination and Prevention
A commercial FIV vaccine has been available in Australia since the early 2000s. It contains inactivated FIV strains and provides moderate protection; studies suggest cats vaccinated with dual subtype vaccines were protected against some FIV strains. However, the vaccine is considered non core and may not protect against all virus subtypes. Vaccinated cats will test positive for FIV antibodies for life, making future testing difficult. Discuss the benefits and risks with your veterinarian.
Preventive Strategies Include:
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Neuter Your Cat: Desexing reduces roaming and aggression, decreasing the chance of bites.
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Containment: Keep cats indoors or build a secure outdoor enclosure. Use a deluxe container litter box and negative ion deodoriser to maintain a clean, odour free home.
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Routine Health Monitoring: Check your cat’s mouth, ears and coat weekly. Offer cat grass kits to aid digestion and prevent hairballs, and reward them with nutritious treats for cooperative behaviour.
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Vaccination: If your cat goes outdoors or lives with FIV positive cats, discuss vaccination with your vet. An initial series of three injections followed by annual boosters may be recommended. Even vaccinated cats should be kept indoors and monitored for fights.
Living with an FIV Positive Cat
Cats with FIV deserve loving homes and can cohabit peacefully with non infected cats if there is no fighting. To minimise risk:
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Provide Resources: Use multiple litter boxes and food stations to prevent competition. A deluxe cat litter box with high sides helps elderly or arthritic cats. Scoop daily and use health monitoring pH litter to detect urinary issues early.
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Hygiene: Wash bowls and bedding regularly. Use a cat grooming brush to remove loose fur and monitor for sores.
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Monitor Appetite and Elimination: Changes in appetite, weight, urine or stool can signal illness. Articles like Why Is the Cat Urinating Blood? and How Long Can Cats Go Without Pooping? provide guidance on when to seek veterinary advice.
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Love and Enrichment: Spend quality time playing with your cat using safe toys and provide cosy bedding. Mental and physical stimulation strengthen the bond and support immune health.
Take Home Message
Feline immunodeficiency virus is a significant but manageable condition in cats. It is chiefly spread through bite wounds; male outdoor cats are most at risk. Early testing, desexing, containment and vaccination together with good nutrition and regular veterinary care dramatically improve outcomes. Michu encourages Australian pet parents to stay informed about FIV, provide a safe indoor environment and monitor their cat’s health using innovative tools like our health monitoring litter and cat health pellets. With attentive care, FIV positive cats can enjoy the same love, comfort and companionship as any other feline.