Yes, a vaccinated cat can still get FIV (Feline Immunodeficiency Virus) because the vaccine offers limited protection, especially against different viral strains, and the best defense is preventing bites from infected cats, ideally by keeping cats indoors. Vaccination causes vaccinated cats to test positive on FIV tests, making diagnosis tricky, so most vets don't recommend it, preferring prevention like neutering and indoor living to avoid deep bite wounds, the main transmission route.

How did my indoor cat get FIV?

Feline immunodeficiency virus (FIV) is yet another nasty cat disease caused by a retrovirus. FIV is transmitted through the introduction of infected bodily fluids into the tissues. Most often this happens through a bite wound, making outdoor male cats who are prone to fighting at the highest risk.

Can vaccinated cats get FIV?

Vaccinated cats will test positive for FIV on common screening tests — making it hard to tell if they're truly infected. This can cause major issues for cats who move homes, end up in a shelter, or need a definitive diagnosis down the road. That's why we do not recommend the FIV vaccine for most cats.

Can a cat get FeLV if they are vaccinated?

Vaccination is not totally effective in every case. If you have several cats and discover that one of your cats is infected with FeLV, vaccination of the others does not guarantee that they will not become infected. The only way to ensure that infection is not transmitted is by isolating your infected cat.

How to tell if a cat has FIV?

Symptoms Can Be Subtle

1. Recurring infections (especially in the mouth, eyes, or skin)
2. Weight loss.
3. Poor coat condition.
4. Fever.
5. Swollen lymph nodes.
6. Dental issues.
7. Overall tiredness or changes in behavior.

Feline Leukemia Virus (FeLV)

Are most stray cats FIV positive?

Prevalence in healthy cats from the United States and Canada with antibodies to FIV can be as low as 1.2% (6). Free-living, unowned cat populations in North America may have prevalence rates for antibodies to FIV ranging from 2.3% to 22% (7–10).

Why was the FIV vaccine discontinued in the USA?

It is important to know that the one existing FIV vaccine was discontinued in the United States and Canada because it is notorious for causing false positives on FIV tests.

What is the 3 2 1 rule for cat vaccination?

The "3-2-1 rule" for cat vaccines is a guideline to monitor for rare, but serious, injection-site sarcomas (cancers): if a lump at the injection site lasts 3 months or longer, is bigger than 2 centimeters, or is growing larger after 1 month, it needs a biopsy to rule out cancer, as recommended by the American Animal Hospital Association (AAHA) and American Association of Feline Practitioners (AAFP) guidelines, the American Veterinary Medical Association (AVMA), and the ABCD vets (ABCD cats & vets).
 

Is FIV in cats a big deal?

FIV initially results in a short-lived illness that's often not even noticed by a cat's owner. Cats then enter a stage of progressive immune system decline, but many remain without symptoms for many years. In fact, research shows that FIV cats may have a similar life expectancy to uninfected cats.

What are the neurological symptoms of FIV?

Specific neurological changes included anisocoria, delayed righting reflex and delayed pupillary reflex, as well as delayed visual and auditory evoked potentials, and marked alterations in sleep patterns similar to those reported for human immunodeficiency virus (HIV)-positive individuals.

What is worse, FIV or FeLV?

FeLV (Feline Leukemia Virus) is generally considered worse and more immediately life-threatening than FIV (Feline Immunodeficiency Virus) because it more directly causes cancers (like lymphoma) and severe immune suppression, leading to shorter survival, while FIV weakens the immune system, allowing for long, comfortable lives with proper care, though it eventually leads to AIDS-like symptoms. FeLV is also more contagious, spreading through saliva and shared items, making management in multi-cat households harder, whereas FIV spreads through deep bite wounds, making it easier for indoor cats to coexist, notes VCA Animal Hospitals and Purple Cat Vet. 

Can cats get FIV from a litter box?

How is it transmitted? FIV is spread between cats through blood transfusions, deep bite wounds, and less commonly, through intercourse or an infected mother's milk to nursing kittens. Sharing a litter box, sleeping area, toys, water bowl or other items will NOT transmit FIV between cats.

What happens if a cat with FIV bites you?

At least one such study has been conducted (and I was one of the guinea pigs), and no evidence of infection was found in anyone, even those who'd been bitten by FIV infected cats or accidentally injected with virus.

Can my cat get FIV if vaccinated?

There is an FIV vaccine, but Best Friends does not recommend it because the vaccine does not have the best efficacy, and after a cat is vaccinated for FIV the cat will test positive for the virus.

What is the 3:2:1 rule in cats?

The "3-2-1 Rule" for cats is a guideline for monitoring injection sites for lumps after vaccinations, indicating potential Feline Injection-Site Sarcomas (FISS); a lump needs veterinary investigation if it's present for 3 months, is larger than 2 centimeters, or grows after 1 month, prompting a biopsy to rule out cancer. This helps differentiate normal inflammation from aggressive tumors, with biopsy recommended for concerning signs, especially since FISS are serious but rare.

Are cats with FIV more affectionate?

An important part of adopting an FIV+ cat is understanding that these kitties are just as loveable and affectionate as non-infected kitties. They need to be loved and cherished in return, maybe even more than an FIV negative kitty since, as mentioned above, keeping them happy and stress-free is good for their health.

Can my cat get feline leukemia if vaccinated?

Although there is always a slight risk of a cat developing feline leukemia even after vaccination, this risk is low and is very uncommon for most pet cats. Generally, this negative result is seen in cats who are strays. Otherwise, this injection is an excellent way to provide some protection for your feline friend.

Can you tell if kittens have FIV?

To clarify their infection status, kittens younger than six months of age that test positive for FIV should be retested at 60-day intervals until they are at least six months old. If their antibody test remains positive after six months old, they almost certainly have a true infection.

Should feral cats with FIV be euthanized?

ACR does not recommend euthanizing cats with FIV and has cared for many healthy FIV feral cats. However, for conditions that require long-term, in-house care and where treatment is not possible, it is more humane to euthanize the cat than it would be to release her back outside.

What is the 3-3-3 rule for stray cats?

The 3-3-3 rule for new cats (including strays or rescues) is a guideline for their adjustment, suggesting 3 days to decompress (scared, hiding), 3 weeks to learn routines and start settling in, and 3 months to feel truly at home, build bonds, and show their true personality, emphasizing patience and creating a calm, consistent environment for a smooth transition.
 

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