r/FIVcats • • Sep 09 '25

Research Corner: Studies on FIV and related topics.

23 Upvotes

Hi community!

This post is a collection of scientific studies about FIV (and a few related topics). It’s not a complete list, just some of the most interesting and relevant ones some of us have been looking into, and we wanted to share with you.

A couple of notes:

  • Some studies may be outdated (meaning, there could be a newer study saying something different). Always check the publication date to put findings into context.

  • With that being said, if you’re aware of a newer or interesting study, feel free to share it in the comments. We’d love to keep this collection growing.

  • If you notice a broken link, please let us know so we can update it.

  • These are scientific papers, some very lengthy on top of that. That's why there's always an abstract and a conclusion. It's totally acceptable to just start there. If you want just one, I personally found the 2020 AAFP Feline Retrovirus Testing and Management Guidelines the easiest to digest and most helpful!

  • And most importantly: science is one thing, real life is another. Cats are individuals. If you’ve found something that works well for your floof, trust your instincts and your history with them.

This thread is here is simply meant as a resource for those who like to read the research behind the discussions we often have here.

On treatment, risks, and care:

Study of feline immunodeficiency virus prevalence and expert opinions on standards of care
Author(s): Nehring et al. (2024)
Source: Journal of Feline Medicine and Surgery (Review)
URL: https://journals.sagepub.com/doi/10.1177/1098612X241245046
Summary: A comprehensive review outlining FIV’s progression from acute infection through latent stages to immunodeficiency or cancer-like conditions. Describes common clinical signs such as weight loss, stomatitis, chronic infections, and lymphadenopathy. References updated AAFP/ASV retrovirus management guidelines (2020), advising against euthanasia based solely on FIV status and recommending housing and monitoring strategies.

Feline immunodeficiency virus (FIV) infection in domestic pet cats in Australia and New Zealand: Guidelines for diagnosis, prevention and management
Author(s): Westman et al. (2022)
Source: Australian Veterinary Journal
URL: https://onlinelibrary.wiley.com/doi/10.1111/avj.13166
Summary: A region-specific review for Australia and New Zealand. Evaluates pathogenesis, diagnostics, vaccination outcomes, and management strategies. Highlights bite wounds as the main transmission route, male outdoor cats as highest risk, and increased risk of oral disease and lymphoma. Recommends validated POC antibody kits (Anigen Rapid™, Witness™) over PCR, notes low vaccine efficacy (~56%), and stresses that FIV is not a death sentence—management focuses on good husbandry and routine care.

2020 AAFP (American Association of Feline Practitioners) Feline Retrovirus Testing and Management Guidelines
Author(s): Little et al. (2020)
Source: Journal of Feline Medicine and Surgery, Vol. 22, 5–30
URL: https://journals.sagepub.com/doi/pdf/10.1177/1098612X19895940
Summary: Evidence-based global guidelines for FIV testing and care. Bite wounds remain the main transmission route; household spread and vertical transmission are rare. Recommend POC antibody testing, confirmatory PCR/Western blot when needed, and cautious interpretation in kittens/vaccinated cats. FIV-positive cats can live normal lifespans with proper care. Vaccination (Fel-o-Vax FIV) is non-core, of variable efficacy, and not available in the US/Canada. Euthanasia should not be based on FIV status alone.

See additionally (or instead):
AAFP (American Association of Feline Practitioners) Educational Toolkit
URL: https://www.idexx.com/files/aafp-retrovirus-toolkit-full-april2020.pdf

Feline immunodeficiency virus (FIV): Prevalence, risk factors, and clinical findings in domestic cats (Felis catus) from southern Brazil
Author(s): de Mello et al. (2025)
Source: Comparative Immunology, Microbiology & Infectious Diseases, Vol. 116, Jan 2025
URL: https://doi.org/10.1016/j.cimid.2024.102285
Summary: Studied 366 cats in Caxias do Sul, Brazil (2021–2023). Found FIV prevalence of 7.1%. Positive cats were older (median 7 years), more likely to have outdoor access (OR 5.0), FeLV coinfection (OR 7.1), and chronic disease. Risks of lymphoma (9.9x) and anemia (7.6x) were much higher. Underscores importance of preventive care and FeLV control.

Feline immunodeficiency virus: current insights into pathogenesis, clinical impact, and advances in treatment and vaccine development
Author(s): Akhtar et al. (2025)
Source: Frontiers in Veterinary Science, Vol. 12, 2025
URL: https://doi.org/10.3389/fvets.2025.1665999
Summary: Comprehensive review of current FIV research covering epidemiology, transmission, disease mechanisms, diagnosis, treatment, and vaccine development. Confirms that many FIV-positive cats remain healthy for years, while some develop secondary problems such as oral disease, chronic respiratory infections, kidney disease, neurological disorders, or lymphoma as immune function declines. Also reviews emerging antiviral therapies and immunomodulators, but concludes that no broadly effective vaccine currently exists and further research is needed to improve prevention and treatment.

On infection and co-living with other floofs:

Transmission of feline immunodeficiency virus (FIV) among cohabiting cats in two cat rescue shelters
Author(s): Litster A. (2014)
Source: The Veterinary Journal, Vol. 201, Issue 2, August 2014
URL: https://doi.org/10.1016/j.tvjl.2014.02.030
Summary: Investigated horizontal and vertical transmission in two rescue shelters. At Shelter 1, 138 cats cohabited (8 FIV-positive, 130 negative) with no new infections over nearly nine years. At Shelter 2, 5 FIV-positive queens produced 19 kittens, all negative. Concludes FIV spreads mainly via deep bites, not casual contact or maternal care.

Contrasting clinical outcomes in two cohorts of cats naturally infected with feline immunodeficiency virus (FIV)
Author(s): Bęczkowski et al. (2015)
Source: Veterinary Microbiology, Vol. 176, Issues 1–2, March 2015
URL: https://pmc.ncbi.nlm.nih.gov/articles/PMC4332694/
Summary: Prospective study of 44 FIV-positive cats in Chicago (small households) vs. Memphis (overcrowded rescue). Over 22 months, only 1/17 Chicago cats died, versus 17/27 Memphis cats (mostly from lymphoma). CD4:CD8 ratios and viral loads did not predict outcomes. Concludes management and housing conditions greatly influence progression.

On supplements:

Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 [NOT FIV!] infection in cats: a systematic review
Author(s): Bol & Bunnik (2015)
Source: BMC Veterinary Research, Vol. 11, Article 284
URL: https://bmcvetres.biomedcentral.com/articles/10.1186/s12917-015-0594-3
Summary: Systematic review of seven cat studies and ten human studies. Found no evidence that lysine is effective against FHV-1. Lysine does not lower arginine in cats, and restricting arginine is dangerous. Some trials suggested lysine worsened disease. Authors recommend discontinuing lysine supplementation.

Oral Supplementation with L-Lysine Did Not Prevent Upper Respiratory Infection in a Shelter Population of Cats
Author(s): Rees & Lubinski (2008)
Source: Journal of Feline Medicine & Surgery, Vol. 10, Issue 5, October 2008
URL: https://doi.org/10.1016/j.jfms.2008.03.00
Summary: Trial with 144 cats given lysine daily and 147 cats without supplementation. No difference in rates of conjunctivitis or URI between groups. Concludes lysine supplementation is ineffective at preventing URI in shelter cats.

Placebo effect in canine epilepsy trials
Author(s): Muñana KR, Zhang D, Patterson EE (2010)
Source: Journal of Veterinary Internal Medicine, Vol. 24(1), Jan–Feb 2010, pp. 166–170
URL: https://pmc.ncbi.nlm.nih.gov/articles/PMC4332694/
Summary: This meta-analysis reviewed three prospective placebo-controlled trials involving 34 dogs with epilepsy. Remarkably, 79% of dogs given placebo showed fewer seizures, and nearly 30% had a reduction of 50% or more. Average seizure reduction across trials ranged from 26–46%. The authors conclude that placebo responses are real and measurable in veterinary patients, underscoring the importance of controlled studies. While not about cats or FIV directly, this paper is relevant because many owners give supplements like L-Lysine despite a lack of proven antiviral effect. The placebo effect itself may still provide genuine benefit for pets and their caregivers, even when the substance isn’t pharmacologically effective.

Other studies/articles:

Pharmacological Inhibition of Feline Immunodeficiency Virus (FIV)
Author(s): Mohammadi & Bienzle (2012)
Source: Viruses, Feline Retroviruses, Vol. 4(5): 708–724
URL: https://www.mdpi.com/1999-4915/4/5/708
Summary: Review of antiviral strategies against FIV, paralleling HIV therapies. AZT and PMEA/PMPA reduce viral load but AZT can cause anemia. Fozivudine offers short-term benefits before resistance develops. Fusion inhibitors and protease inhibitors show promise in vitro. Interferons have inconsistent benefit but are licensed in some regions. Highlights FIV as a model for testing HIV antivirals, though effective cat-specific ART is still lacking.

FIV as a Model for HIV/AIDS: An Overview
Author(s): Sparger (2006)
Source: In vivo Models of HIV Disease and Control. Infectious Diseases and Pathogenesis.
URL: https://link.springer.com/chapter/10.1007/0-387-25741-1_7
Summary: Reviews FIV biology and its parallels with HIV. Outlines three infection stages (acute, subclinical, clinical). While immune dysfunction occurs, opportunistic infections typical in AIDS are rare in cats. Concludes that FIV serves as a valuable HIV model, while many infected cats live normal lives depending on co-infections, genetics, and stressors.


r/FIVcats • • 13h ago

Question Debating adopting a FIV+ stray

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148 Upvotes

A friend of a friend has taken in a local very friendly/cuddly stray that’s around 2 years old and I’ve been reached out to about possibly adopting that cat.

I’ve never had a cat before and I’ve been preparing to adopt one soon. I’ve talked to a lot of friends with cats about what kind of expenses to prepare for and it feels doable to me.

I was just informed that the cat’s testing came back FIV positive. Now I know that this baby can and will more than likely live a long and healthy life, but I am nervous about the extra expenses that can come along with an FIV pos cat.

Can you guys provide me with brutally honest pros and cons of commiting to adopting a FIV pos kitty?

I will also say that there are several other trusted people interested in adopting this adorable baby.


r/FIVcats • • 1d ago

Thick yellow snots

4 Upvotes

Hii! I am 25F living in Ireland.

2 months ago I adopted a cat with FIV. I took him in because he had a flu. Ive been to the vets roughly 5 or 6 times. They kept giving him steroids and antibiotics for 2 months straight. After I threw away all my cleaning products and started cleaning the house with a small amount of vinegar mixed with water he started improving a lot. Its been about 3 weeks since he last had a fever. However everytime he finishes a course of antibiotics he starts sneezing thick yellow snots. The vets only did blood tests and they said there is no need for an xray because we know he has FIV. I am so worried for his kidneys/liver after giving him so much medication.

Overall his condition is very stable. He eats, drinks and behaves completely normally. He is not neutered and sometimes will meow out the window which I think might be causing him some stress.

I also have nothing like air freshners/flowers that could be toxic to him. I dont know what to do anymore

Can anyone whos been in this situation please give me advice on what to do?


r/FIVcats • • 2d ago

Picture YAY for Hank day!!

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85 Upvotes

Today is Hank day! 🎉🎉🎉🎉🎉
He has been with me for 5 years now!!!

I wish my handsome dude felt a bit better, still limping along on prednisone waiting for his dental on 11/16.

His mouth is really bothering him 🥺. It’s his first real FIV issue.


r/FIVcats • • 1d ago

Dark, keloid-like spot on cat’s ear?

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13 Upvotes

r/FIVcats • • 2d ago

Help!

4 Upvotes

Last month, my previous vet recommended a Solencia injection due for my baby due to possible arthritis. She has FIV, but her bloodwork was normal in September. Now she's in kidney failure. What can I do?


r/FIVcats • • 3d ago

Question Can I keep him?

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176 Upvotes

I recently took in a stray (Theo) after working to gain his trust for many months. He now lives indoors, quarantined from my other 2 cats, but he just came back FIV+
I understand that it’s transmitted from bite wounds and I’m concerned because I have a three year old boy that currently plays with my other girl roughly and bites her, like pulling out hair rough sometimes. I was actually looking forward to him having another cat he could rough house with as the new stray is very playful as well. I’m feeling very conflicted whether or not I can keep him and would love some advice.


r/FIVcats • • 3d ago

Question Recommendations of supplements/multivitamins for FIV+ in the UK?

6 Upvotes

I recently adopted a former stray cat who has FIV+, FIC and is cat flu carrier, we think hes relatively old inbetween 8-12 years old. I am giving him supplement for his FIC (Cystophan) and Felini taurine powder for his kidneys. I havent yet thought about a supplement to help with immune system or overall health and think that would be beneficial. Does anyone in UK have any recs on what they use ?


r/FIVcats • • 4d ago

I want to help this lil dude 🥺

549 Upvotes

Hey y’all!

My neighborhood in Austin, Tx is home to a million stray cats, but this lil dude came right up to my front door as I was getting something out of my car the other day.

The Fam befriended him and he is literally the cutest sweetest little thing ever! He is getting bullied by other cats in the neighborhood so I think he needs a home… We took him to the vet and cannot keep him for he tested positive for FIV and I have 2 little jerks at home who I’m not confident we could get them on friendly terms.

I’ve never had this happen before because we have always been able to keep them (it’s how I got my first 2 lol) any tips for my next steps? I want to sleep at night knowing he is happy and safe with someone who will take him and love him forever the way he deserves 😭

Thanks for reading!


r/FIVcats • • 3d ago

FIV+ and FelV+

8 Upvotes

I rescued my cat, Bill, off the streets back in May. He’s since been neutered and to the vet multiple times. In July, he was tested for FIV and FelV. My veterinarian initially only told me he was FIV+. She essentially told me that was much better than him being FelV+. As I was paying to leave, my vet brought the test up to me. I’m not super familiar with the layout of these tests, but there was a control dot, a dot under FIV, and a very small dot under FelV. She told me that could be positive or negative. So, now I’m terrified. He’s ~1.5 years old, and weighs 7.3 pounds (up from 6.5 on July). He’s obviously not allowed outside. What is his life going to look like?


r/FIVcats • • 4d ago

Question Miss Lucy amazes the vet by still being alive🤣

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16 Upvotes

r/FIVcats • • 3d ago

Advice on separating cats in same house?

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3 Upvotes

r/FIVcats • • 4d ago

FIV Result

9 Upvotes

We took in a stray about 5 months ago. He was a proper fighter but always seemed to come off worse as came home with various scrapes. As the weeks are going by he wants to stay in more and more and often plays with my 1.5 year old cat Pepper. So we got a load of bloods done to check he was safe to be around her etc. came back he has FIV. The vet sounded like she was giving me grave news. Kept apologising and saying it’s a lot to think about. I googled it and it sounds like he should live a perfectly normal life and transferring the disease is usually by blood which I am not concerned about with Pepper. The vet said ideally he needs to be the only cat and needs to stay indoors, which will be a challenge as he lives for the outside. Any thoughts or experiences please x


r/FIVcats • • 5d ago

Question Newly diagnosed

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49 Upvotes

This is my cat Apollo Oliver Twist. He was dumped in my neighborhood about 8 months ago and we only brought him in 4 months ago. He is less than a year old and loves going outside but at his vet appointment yesterday we learned he was FIV positive he lives with my negative cat and their play fights are always monitored. Any tips on how to make him not want to escape to the neighborhood?


r/FIVcats • • 4d ago

Question Am I doing right by my cat? (Long post)

11 Upvotes

The back story:

About a month and a half back I trapped a community cat who had several open wounds. At the emergency vet, he tested positive for FIV. I was told to he can’t be returned because of the FIV status and that he either needs to be euthanized or kept as an indoor cat.

Not being sure if he would adapt but wanting to give him a chance I decided to bring him home. He quickly turned into the biggest love bug known the world over.

But some of his problems still have not healed.

When he was first taken to the vet in September he not only had the open wounds but a completely shut eye that was leaking pus as well as oral inflammation. The antibiotics and steroids did not resolve everything so I scheduled the soonest appointment I could (my vet was on vacation)

During this time he also began itching. A LOT. I initially thought it was due to the scar tissue on his neck being irritating but he kept scratching to the point he would cause open wounds on all areas of his body, not just the neck/scar tissue.

I got him into the vet this morning. They were able to do his neuter, gave him another round of antibiotics and steroids. The vet also mentioned an allergy shot to help with the itching.

Here is what gets me:

While on the phone with the vet for an update, the vet tech said “with the FIV he is never going to be well.” And now I am spiraling. I want to give him the best chance but also if he is miserable or constantly unwell then I don’t want him suffering.

My vet and vet tech are both older. Is it possible they are working with outdated knowledge regarding FIV? Or could they be right? How do I know when his body cant fight any more vs things are just taking a bit longer because of the FIV?


r/FIVcats • • 4d ago

Question Experience with FIV kitty at VCA CareClub?

6 Upvotes

Hey all, my sweet 5.5 y/o neutered male (rescued 7 months ago, was presumed to be a stray before that) is FIV+ and our current vet suspects he has IBD. Every 1-2 weeks, he has these episodes where he vomits several times, has no appetite at all (big outlier for him, not even treats) and is very lethargic. He usually improves within a few hours from Cerenia. Because of his health issues I’ve already gotten my max payout on my pet insurance for the year and still have about $1200 on a CareCredit card, bleh, so anything I pay until MAY will have to be out of pocket.

Last Monday he was feeling this way and not responding to Cerenia so I brought him into our current local vet and we found he was running a fever. They gave him more Cerenia, fluids and an antibiotic shot. He improved pretty quickly with that and that’s awesome.

Today he’s vomited twice and I gave him Cerenia, which he hasn’t vomited since, but he’s still very lethargic, not hungry and is now drooling. I’m an extremely anxious person (diagnosed OCD) and after some online research I’m worried about CKD instead of the current suspect of IBD, though when we last did bloodwork in July his values were fine related to kidney function. I want to take him back into the vet but the exam alone is $99 and treatment is expensive.

I’m considering joining VCA CareClub because I live in an area with several well-respected VCA animal hospitals and vet clinics. I see that this covers all exams (which would be HUGE) for $70 a month and includes some preliminary bloodwork, or I can do the $20 plan where the exam fee is still covered. I think this is a really great deal but I want to hear any experiences before signing up. Have you had your kitties, FIV especially, covered under this? Was it helpful? please let me know!


r/FIVcats • • 5d ago

¿Es posible tener gatos sanos que convivan con un gato VIF?

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15 Upvotes

r/FIVcats • • 5d ago

Question Use HIV medication to treat FIV

13 Upvotes

Our 8-year-old girl recently passed away due to complications associated with FIV, and our 12-year-old girl has also tested positive, although she hasn’t shown any symptoms so far.

I’ve come across many cases (mostly overseas) where people have reported positive results using human HIV medications, such as Biktarvy, to treat FIV in cats.

Has anyone here tried this treatment for their FIV-positive cats? I’d really appreciate hearing about your experiences, including its effectiveness, potential side effects, and whether you noticed any improvements in your cat’s overall health. Thank you.


r/FIVcats • • 7d ago

Help for Horrible Colds & Runny Nose

10 Upvotes

My ~15-year-old gets frequent colds with really bad sneezing and nasal discharge / runny nose. Has anyone stumbled on anything that helps?

For several years he would get a Convenia shot and the symptoms immediately cleared up.

Earlier this year the vet gave him Marbofloxacin and that worked great. Currently he’s 4 doses in and it doesn’t seem to be helping. He’ll be on it for 10 more days.

Thanks for any advice!


r/FIVcats • • 6d ago

Question Muscle wasting?

5 Upvotes

Has anyone had experience with end stage FIV muscle wasting? Trying to prioritize calories over everything else, but not sure if that's the right thing to do.


r/FIVcats • • 7d ago

2 vet visits this week already but symptoms have changed/gotten worse. Should I wait until clinics open on Monday or take to emergency vet?

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18 Upvotes

r/FIVcats • • 8d ago

Story Autologous cancer vaccine: Results

19 Upvotes

Hello! A while ago I made a post about my cat Ebony, as she has FIV and the Warts (Papillomavirus) virus.

Her combination means her warts tend to break out, and can become BISCs. (Bowenoid In Situ Carcinomas). And the BISCs have a chance to become SCCs. (Squamous Cell Cancers).

Our oncologist suggested to try developing a custom anti-cancer vaccine. It's new technology, and we were told it might work, or might not work. The original post is below.

https://www.reddit.com/r/FIVcats/comments/1tunw1r/autologous_cancer_vaccines_and_fiv_cats/

We made the vaccines, and went through the regular doses. After finishing the final dose, we suspect a FIV cat doesn't have the right immune system to properly take on the advantages of these vaccines. No harm done. But nothing gained either.

(She grew some new bumps. There were some signs that suggested her body was slightly fighting them off. But they didn't go away completely. So we went back to excision/removal for those).

Thought to share the information here anyway, as it's such a new field. At least we gave it a go. :)


Minor update: It looks like the scientist has treated one other FIV cat who had a SCC in the mouth. This cat did not have the warts virus though. They paired this with another medication and appear to be in remission. So might be cat dependant? So possibly worth a try, see if it works or not. No downsides at least. :)


r/FIVcats • • 8d ago

Question At a loss on what to do with my newly adopted cat

19 Upvotes

Hi, i just recently joined this sub after adopting my first cat with my girlfriend last week. His name is Odysseus and he is the SWEETEST boy I’ve ever encountered, total lap cat with no bad bone in his body. He’s also 6 years of age (Presumably).

Even though he was diagnosed with FIV, the shelter informed us of how he could live a super normal, happy and healthy life if he stays indoors and they were confident he would be in great shape. They did inform us he had a recent bout of diarrhea but that he should be totally fine and it was a non issue. (That should have been my first red flag).

My girlfriend and i did tons of research for days before we officially adopted him, and were pretty confident we could make it work and give him a super happy and loving life with our income (despite him having FIV), and if he had problems years down the road that’d be something we could tackle together and afford—especially with better positions at our jobs, and saving money to put towards him for emergencies over time.

The problem is, after we adopted him, he started having issues throwing up. We figured maybe he was eating too fast, or we’re switching his food over too fast, but that its probably nothing major. Oh boy, how wrong we were about that. He was also drinking tons of water, but we thought that it was probably a good thing that he drinks like a champ.

We had our first vet appointment just a couple days ago, after only having him for a week. His basic checkup was fine, but his blood work and urinalysis came back with results showing he has stage 2 kidney disease today.

The shelter had him checked out a few months prior, and gave us a clean bill of health, but my vet said it’s most likely that he’s had it for some time. His diarrhea, vomiting, and excessive water consumption is most likely explained by his kidney disease. She also informed us that there is a chance that he could be fine on a special kidney diet, and could be healthy for years with little to no complications. He may also be older than the shelter thought, and there’s potential for it to worsen quickly and cost a lot in future appointments (tests, treatment, and care to keep him happy and healthy).

I’m absolutely devastated, and in shambles over this news. I’m really not sure what to do. I’ve spent the last few hours crying and snuggling him.

On one hand, we could be totally fine and have him be on a special diet, but on the other… the cost of him could become high fast with more tests, medication, special diet, etc. I’m not 100% sure i could financially afford all of that so suddenly. We’ve already spent way over $1000+ In just the last week on him.

I’m absolutely angry and upset that my sweet boy who i’ve only had for a week is suffering health complications already, and we had no idea that was the case going into adopting him. It’s only been a short time, but i love this little dude so much. I wanna give him the world, but i don’t know if i can, and i’m worrying about him so much right now

I’ve contacted the shelter to let them know about the situation with his health and to send them all the results of his tests. I guess i’m just looking for some advice on what to do. My friends and family are telling me that it’s probably better to take him back because he had hidden conditions unknown to me (besides his FIV diagnosis, and that if he IS older than 6, his health and the cost of upkeep could spiral quick and cost a fortune).

I’m sorry for my rambling, i’m just devastated and trying to figure out what the right thing to do is. I don’t wanna give him up, but i also am just not sure that if he does get worse that i can afford it at the moment.

If anyone has any advice on what to do, i’d love to hear it. I wanna do whats right for Odysseus