What is FIV?
FIV (Feline Immunodeficiency Virus) is a common viral infection in cats that targets the immune system, especially certain white blood cells. Many cats live normally for years, but over time the weakened immunity can make them more vulnerable to secondary infections (things that a healthy immune system might usually handle easily).
Important reassurance: Many FIV+ cats can live average lifespans, especially if they’re not also infected with FeLV (Feline Leukaemia Virus) and are well cared for.
How do cats get FIV?
The main route: deep bite wounds
FIV is primarily spread through bite wounds from an infected cat — which is why it’s most associated with outdoor fights.
What doesn’t usually spread FIV
Casual contact is not considered an efficient route:
• sharing bowls
• grooming each other
• living together peacefully
In a stable home where cats don’t fight, the risk is considered low.
Mother-to-kitten?
It can happen, but is described as rare — risk increases if the mother becomes infected during pregnancy.
Who is at higher risk?
• unneutered males
• cats with outdoor access
• cats that fight/roam
These are repeatedly flagged as the highest-risk group.
Is FIV contagious to humans or dogs?
No. FIV is species-specific (felines). There is no evidence it infects humans.
It does not infect dogs either.
The stages of FIV (and why cats can look “fine” for years)
Cornell describes three phases:
1. Acute phase (often missed)
Typically 1–3 months after infection: mild fever, lethargy, reduced appetite, enlarged lymph nodes — sometimes so mild it’s mistaken for a “bug.”
2. Asymptomatic/latent phase (months to years)
Cat can look completely healthy while the virus replicates slowly. Some never progress to severe disease.
3. Progressive phase
Immune suppression becomes more significant and secondary infections and immune-related issues become more likely.
Common signs owners might notice
FIV itself isn’t always the visible problem — it’s what follows from a weakened immune system. Cornell lists issues such as:
• recurring/chronic infections (skin, eyes, urinary tract, upper respiratory)
• gum disease / gingivostomatitis and dental problems
• weight loss (often an early warning sign)
• occasionally neurological signs (seizures/behaviour changes)
• increased risk of some cancers and immune-mediated blood disorders
Key takeaway: an FIV+ cat with new symptoms should be checked early, because infections may need faster, longer, or stronger treatment.
Diagnosis & testing (what the results actually mean)
The common first test: antibody (ELISA) blood test
Most in-clinic screening tests look for antibodies — once infected, cats usually keep antibodies for life.
Why one test isn’t always the whole story
Because it’s an antibody test, special situations can cause confusion:
• a single positive may need confirmation (your vet may use a different confirmatory test)
• kittens can carry maternal antibodies for a period (your vet will advise timing/retesting)
• PCR testing (detecting viral genetic material) exists, but Cornell notes it can produce false positives and false negatives, so it’s not usually the first choice for screening, though it can help in certain confirmation situations.
Practical rule: If your cat is FIV+ on a screening test, ask your vet what confirmatory approach makes sense for that cat (age, history, symptoms, vaccination history, etc.).
Is there a cure?
There is no treatment that eliminates FIV from the body.
Care is about reducing infection risk, catching problems early, and supporting long-term health.
Treatment & management (what actually helps)
The big pillars of FIV care
1) Keep them indoors
This protects your FIV+ cat from picking up infections and prevents spreading FIV via fights.
2) Neuter/spay
Reduces roaming and fighting, lowers spread risk, and supports a calmer life.
3) Regular vet checks
Cornell recommends at least every 6 months, with close attention to gums, eyes, skin, lymph nodes, and weight trends. Annual bloodwork and urinalysis are commonly recommended.
4) Nutrition & food safety
Feed a complete balanced diet; avoid raw meat/eggs and unpasteurised dairy to reduce food-borne infection risk.
5) Act fast on illness
Because many problems are secondary infections, prompt vet care matters. Some cats may need longer antibiotic courses than non-FIV cats.
6) Dental care is not optional
Gum and mouth inflammation is common; proactive dental plans can dramatically improve comfort and quality of life.
Antivirals?
Cornell notes some human HIV drugs have been used in limited ways. For example, AZT (zidovudine) may help certain severe mouth inflammation or neurologic disease, but it has not been shown to prolong survival and can have significant side effects — it’s a vet-led decision, not a DIY option.
Prognosis (what to expect)
• Many cats stay stable for years, sometimes a normal lifespan, especially with indoor living and good preventive care.
• When severe secondary infections or cancers develop repeatedly, outcomes can become more serious — but this is not the path for every FIV+ cat.
The reality: FIV is often manageable. The goal is a low-stress, indoor, well-monitored life.
Living with other cats (household risk)
Can an FIV+ cat live with FIV-negative cats?
Often, yes — if the household is calm and there is no fighting. Since the main transmission is deep bite wounds, peaceful cohabitation is considered much lower risk.
Best practice precautions
• Test all cats in the household (your vet can advise timing).
• Reduce stress and competition: multiple bowls, multiple litter trays, safe resting areas. Stress may play a role in immune health, and many cats dislike sharing.
• If cats fight: separate and seek behavioural/vet support.
Vaccines: are there any for FIV?
FIV vaccines are not widely available and are only available in a few countries (and not available in some regions).
For most households, prevention relies on reducing exposure (indoor living, neutering, avoiding fights, testing newcomers).
Adoption: why you shouldn’t fear adopting an FIV+ cat
An FIV+ cat can be:
• affectionate, normal, playful
• a perfect single-cat companion
• safe to live with people and dogs
• safe with other cats in the right, stable home
If you can offer indoor safety, routine, and attentive care, adopting FIV+ is often not “taking on a burden” — it’s giving a cat the stable life that helps them thrive.
Quick “FIV owner checklist”
• ✅ Indoor-only
• ✅ Neutered/spayed
• ✅ Vet check every 6 months
• ✅ Annual blood/urine screening
• ✅ Excellent dental care plan
• ✅ Avoid raw diets
• ✅ Parasite prevention
• ✅ Rapid vet visit for any change (weight, appetite, breathing, mouth pain, recurring sneezing/UTIs/skin issues)
(Info is educational and can’t replace your own vet’s advice for your individual cat.)
