Cat HIV (Infomation Supplied by Wikipedia) (Animal Advice Column)

+10 votes
asked Feb 22, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)

Feline immunodeficiency virus

Species of virus

"FIV" redirects here. For the Federazione Italiana Vela, see Italian Sailing Federation.

Feline immunodeficiency virus
Virus classification
Group: Group VI (ssRNA-RT)
Order: Unassigned
Family: Retroviridae
Subfamily: Orthoretrovirinae
Genus: Lentivirus
Species: Feline immunodeficiency virus

Feline immunodeficiency virus (FIV) is a lentivirus that affects cats worldwide. From 2.5% up to 4.4%[1][2] of cats worldwide are infected with FIV. FIV differs taxonomically from two other feline retrovirusesfeline leukemia virus (FeLV) and feline foamy virus (FFV), and is more closely related to human immunodeficiency virus (HIV). Within FIV, five subtypes have been identified based on nucleotide sequence differences coding for the viral envelope (env) or polymerase (pol). FIV is the only non-primate lentivirus to cause an AIDS-like syndrome, but FIV is not typically fatal for cats, as they can live relatively healthily as carriers and transmitters of the disease for many years. A vaccine is available although its efficacy remains uncertain. Cats will test positive for FIV antibodies after vaccination.[3]

FIV was first isolated in 1986 by Dr. Smith at the UC Davis School of Veterinary Medicine in a colony of cats that had a high prevalence of opportunistic infections and degenerative conditions and was originally called Feline T-lymphotropic Virus (FTLV).[4] It has since been identified as an endemic disease in domestic cat populations worldwide.[5]






FIV can attack the immune system of cats, much like the human immunodeficiency virus (HIV) can attack the immune system of human beings. FIV infects many cell types in its host, including CD4+ and CD8+ T lymphocytes, B lymphocytes, and macrophages. FIV can be tolerated well by cats, but can eventually lead to debilitation of the immune system in its feline hosts by the infection and exhaustion of T-helper (CD4+) cells.

FIV and HIV are both lentiviruses. However, humans cannot be infected by FIV, nor can cats be infected by HIV. FIV is transmitted primarily through saliva (bites)[citation needed], such as those incurred during territorial battles between males. Cats housed exclusively indoors are much less likely to be infected, provided they do not come in contact with infected cats.

A vigilant pet owner who treats secondary infections can assist an infected cat to live a reasonably long life. The chance that an FIV infected cat will pass the disease on to other cats within a household remains, and increases with serious fighting or biting.[6] There is a quantifiable risk that cats living outside of a home can spread the disease to others and can also spread the disease in a group setting in a shelter. Cats living alone as a single pet, rarely left to roam free, pose a diminished but existent risk.

FIV infects other feline species, and in fact is endemic in some large wild cats, such as African lions.

In the United States

Consensus in the United States on whether there is a need to euthanize FIV infected cats has not been established. The American Associations of Feline Practitioners (an organization in the United States), as well as many feral cat organizations, recommends against euthanizing FIV-positive cats, or even spending funds to test for the virus, as spaying or neutering cats seems to effectively control transmission (spayed / neutered cats are less likely to engage in territorial fights)[citation needed].



The virus gains entry to the host's cells through the interaction of the envelope glycoproteins (from the glycoprotein env) of the virus and the target cells' surface receptors. First the SU glycoprotein binds to CD134, a receptor on the host cell. This initial binding changes the shape of the SU protein to one that facilitates interaction between SU and the chemokine receptor CXCR4. This interaction causes the viral and cellular membranes to fuse, allowing the transfer of the viral RNA into the cytoplasm where it is reverse transcribed and integrated into the cellular genome through non-homologous recombination. Once integrated into the host cell's genome, the virus can lay dormant in the asymptotic stage for extended periods of time without being detected by the immune system or can cause lysis of the cell. (4,5) [7][8]

CD134 is predominately found on activated T cells and binds to OX40 ligand causing T-cell stimulation, proliferation, activation, and apoptosis (3). This leads to a significant drop in cells which have critical roles in the immune system. Low levels of CD4+ and other affected immune system cells cause the cat to be susceptible to opportunistic diseases once the disease progresses to feline acquired immune deficiency syndrome (FAIDS).[9]



The primary mode of FIV transmission is via deep bite wounds, where the infected cat's blood-tainted saliva enters the other cat's bloodstream. FIV may also be transmitted from pregnant females to their offspring in utero, however this vertical transmission is considered to be relatively rare based on the small number of FIV-infected kittens and adolescents .[3][9] This differs from FeLV, which may be spread by more casual, non-aggressive contact since the virus is also present at mucosal surfaces such as those in the mouth, rectum, and vagina, so casual contact cannot be ruled out as a potential transmission.

Risk factors for infection are being of the male sex, adulthood, and outdoor access. One case study conducted in São Paulo found that 75% of the FIV-infected cats were males. Higher rates of infection in males than females makes sense because the primary means of transmission is from biting and most instances of biting in cats occur in fights over territory, an activity more common for males than females.[8]


Disease stages

FIV progresses through similar stages to HIV in humans. The initial stage, or acute phase, is accompanied by mild symptoms such as lethargyanorexiafever, and lymphadenopathy.[9] This initial stage is fairly short and is followed by the asymptomatic stage. Here the cat demonstrates no noticeable symptoms for a variable length of time. Some cats stay in this latent stage for only a few months, but for some it can last for years. Factors that influence the length of the asymptomatic stage include the pathogenicity of the infecting virus and FIV subtype (A-E), the age of the cat, and exposure to other pathogens. Finally, the cat progresses into the final stage (known as the feline acquired immune deficiency syndrome (FAIDS) stage), wherein the cat is extremely susceptible to secondary diseases that inevitably are the cause of death.[8]



Veterinarians will check a cat's history, look for clinical signs, and possibly administer a blood test for FIV antibodies. FIV affects 2-3% of cats in the US and testing is readily available. It should be noted that this testing identifies those cats that carry the FIV antibody, and does not detect the actual virus.

False positives occur when the cat carries the antibody (which is harmless), but does not carry the actual virus. The most frequent occurrence of this is when kittens are tested after ingesting the antibodies from mother's milk, and when testing cats that have been previously vaccinated for FIV. For this reason, neither kittens under 8 weeks nor cats that have been previously vaccinated are tested.

Kittens and young cats that test positive for the FIV antibody may test negative at a later time due to seroreversion, provided they have never been infected with FIV and have never been immunized with the FIV vaccine.

Cats that have been vaccinated will test positive for the FIV antibody for the rest of their lives owing to seroconversion, even though they are not infected. Therefore, testing of strays or adopted cats is inconclusive, since it is impossible to know whether or not they have been vaccinated in the past. For these reasons, a positive FIV antibody test by itself should never be used as a criterion for euthanasia.[10]

Tests can be performed in a vet's office with results in minutes, allowing for quick consultation. Early detection helps maintain the cat's health and prevents spreading infection to other cats. With proper care, infected cats can live long and healthy lives.


Treatment options

In 2006, the United States Department of Agriculture issued a conditional license for a new treatment aid termedLymphocyte T-Cell Immunomodulator (LTCI).[11] Lymphocyte T-Cell Immunomodulator is manufactured and distributed exclusively by T-Cyte Therapeutics, Inc.[12]

Lymphocyte T-Cell Immunomodulator is intended as an aid in the treatment of cats infected with feline leukemia virus (FeLV) and/or feline immunodeficiency virus (FIV), and the associated symptoms of lymphocytopeniaopportunistic infectionanemiagranulocytopenia, or thrombocytopenia. The absence of any observed adverse events in several animal species suggests that the product has a very low toxicity profile.

Lymphocyte T-Cell Immunomodulator is a potent regulator of CD-4 lymphocyte production and function.[13] It has been shown to increase lymphocyte numbers and Interleukin 2 production in animals.[14]

Lymphocyte T-Cell Immunomodulator is a single chain polypeptide. It is a strongly cationic glycoprotein, and is purified with cation exchange resin. Purification of protein from bovine-derived stromal cell supernatants produces a substantially homogeneous factor, free of extraneous materials. The bovine protein is homologous with other mammalian species and is a homogeneous 50 kDa glycoprotein with an isoelectric point of 6.5. The protein is prepared in a lyophilized 1 microgram dose. Reconstitution in sterile diluent produces a solution for subcutaneous injection.



As with HIV, the development of an effective vaccine against FIV is difficult because of the high number and variations of the virus strains. "Single strain" vaccines, i.e. vaccines that only protect against a single virus variant, have already demonstrated a good efficacy against homologous FIV strains. A dual-subtype vaccine for FIV released in 2002 called Fel-O-Vax (ATCvet code: QI06AA10 (WHO)) made it possible to immunize cats against more FIV strains. It was developed using inactivated isolates of two of the five FIV subtypes (or clades): A Petaluma and D Shizuoka.[15] The vaccine was shown to be moderately protective (82% of cats were protected) against subtype A FIV,[16] but a later study showed it to offer no protection against subtype A.[17] It has shown 100% effectiveness against two different subtype B FIV strains.[18][19] Vaccination will cause cats to have positive results on FIV tests, making diagnosis more difficult. For these reasons the vaccine is considered "non-core", and the decision to vaccinate should be made after discussion with a veterinarian and consideration of the risks vs. the effectiveness.[20]



Genome structure of FIV based on available data 2013.

FIV displays a similar structure to the primate and ungulate lentiviruses. The virion has a diameter from 80 to 100 nanometers and is pleomorphic. The viral envelope also has surface projections that are small, 8 nm, and evenly cover the surface.[7]

The FIV virus genome is diploid. It consists of two identical single-strands of RNA in each case about 9400 nucleotides existing in plus-strand orientation. It has the typical genomic structure of retroviruses, including the gagpol, and env genes. The Gag polyprotein is cleaved into matrix (MA), capsid (CA) and nucleocapsid (NC) proteins. Cleavage between CA and NC releases a nine amino acid peptide, while cleavage at the C-terminus of NC releases a 2kDa fragment (p2). The Pol polyprotein is translated by ribosomal frame-shifting, a feature shared with HIV. Cleavage of Pol by the viral protease releases the protease itself (PR), reverse transcriptase (RT), deoxyuridine triphosphatase (dUTPase or DU) and integrase (IN). The Env polyprotein consists of a leader peptide (L), surface (SU) and transmembrane (TM) glycoproteins. In common with other lentiviruses, the FIV genome encodes additional short open reading frames (ORFs) encoding the Vif and Rev proteins. An additional short ORF termed orfA (also known as orf2) precedes the env gene. The function of OrfA in viral replication is unclear, however the orfA-encoded product may display many of the attributes of HIV-1 accessory gene products such as Vpr, Vpu or Nef.

The capsid protein derived from the polyprotein Gag is assembled into a viral core (the protein shell of a virus) and the matrix protein also derived from Gag forms a shell immediately inside of the lipid bilayer. The Env polyprotein encodes the surface glycoprotein (SU) and transmembrane glycoprotein (TM). Both SU and TM glycoproteins are heavily glycosylated, a characteristic that scientists believe may mask the B-cell epitopes of the Env glycoprotein giving the virus resistance to the virus neutralizing antibodies.[7]


Lentiviral vector

Like HIV-1, FIV has been engineered into a viral vector for gene therapy.[21] Like other lentiviral vectors, FIV vectors integrate into the chromosome of the host cell, where it can generate long-term stable transgene expression. Furthermore, the vectors can be used on dividing and non-dividing cells.[21][22] FIV vectors could potentially be used to treat neurological disorders like Parkinson's disease, and have already been used for transfer RNAi which may find use as gene therapy for cancer.[23]

Your answer

Your name to display (Optional - DO NOT USE YOUR REAL NAME):
Privacy: Your email address will only be used for sending this notification and will be deleted after it is sent. Login or become a registered user to avoid having to enter your e-mail again and skipping the verification step below.
Anti-spam verification:
To avoid this verification in future, please log in or register.

Related questions

+10 votes
0 answers 666 views

Canine parvovirus This article is about canine parvovirus type 2. For canine parvovirus type 1, see canine minute virus. Canine parvovirus 2 Electron ... ARTICLES Parvovirus genus of viruses Feline panleukopenia Canine coronavirus species of virus

asked Feb 22, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+9 votes
3 answers 88 views

Hello, everyone. This is the Animal Advice Column Show, and so I'm going to tell you how this works! There is no TV required, just your device. I am your host ... host, GemHeart, and we are closing up for tonight. Bye, and enter your requests below!

asked May 22, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+8 votes
3 answers 143 views

This is my Animal Advice Column logo: Try one for your column! Go to (but don't press "make me business cards". Just copy and paste at the end.). :)

asked Mar 19, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+8 votes
1 answer 56 views

More info on Fancy Rats:

asked Feb 22, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+11 votes
1 answer 63 views

A young fainting goat in the midst of a myotonic "fainting" spell

asked Feb 19, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
1 answer 72 views
+9 votes
1 answer 192 views

Sugar Gliders. With built-in parachutes, sugar gliders--marsupials from Australia and New Guinea-- can leap from a tree and glide, sometimes as far as half a football ... . Instead, all of the females have babies after mating with one or more males.

asked Feb 19, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 53 views Strange Animal Sleeping Habits! Enjoy, and request a video as well!

asked Feb 18, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 42 views Rats: What, When & How! Enjoy the video, and be on the lookout for more to come!

asked Feb 18, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 247 views

My Animal Advice Column is now in business as an official advice column! These are the questions you can ask: How to do a mouth-to-nose resuscitation and ... from the internet or the ©2007 Merck/Merial Manual for Pet Health. All rights reserved.

asked Feb 18, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 75 views

Hey! Do you have a pet, and do you care about his wellbeing? Then muddle no more, and stop here, for your friendly neighborhood KidzSearch Veterinarian has COME! I can help from ... feel worthy to note) Thanks! If you feel it is fatal, GO TO A VET!

asked May 3, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+6 votes
1 answer 57 views

I've had it up and running for about half a month, and no one's asked any questions in it! Please check it out! You can ask any questions about animals, like how ... a vet book, research about pets, etc). So, please! - GemHeart, Animal Advice Column

asked Mar 10, 2017 in Pets / Animals by -GEMHeart- (278,660 points)
+12 votes
1 answer 149 views

Animals Frozen Alive, Crudely Gassed at Petco, PetSmart Supplier Y ou know those plastic tubs that people use to store holiday decorations, old blankets, and clothes in the attic ... TAKE ACTION BY VISTING PETAKIDS.COM OR PETA.COM (!!!

asked Mar 15, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+8 votes
3 answers 950 views

Animal Cruelty Cases By K. Michelle Welch In the last two years, following the much-publicized dogfighting case involving pro football player Michael Vick, animal cruelty ... know or have seen people who abuse animals, report the case to officials!

asked Mar 13, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+9 votes
1 answer 107 views You will cry. This is a disturbing video. Find out the facts of animal abuse in this video:

asked Mar 12, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 65 views

Try using various logo creator websites!

asked Mar 18, 2017 in All Advisors by -GEMHeart- (278,660 points)
+10 votes
3 answers 53 views

I will try to make a video for the show! My face will not be shown, and I hope you'll enjoy it! I will be doing unicorns first, and I hope that I'll be able to upload it! It is called: Animal Advice Column Show: Unicorns and Horses.

asked May 23, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
2 answers 441 views This video is called Gift- Director's Cut. It is about a girl, but you'll see why I put it under my Column when you watch it!

asked Mar 28, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+9 votes
0 answers 53 views

#Animalnation is a project about stopping animal abuse. Join the movement! Post your reasons and how to stop animal abuse under the hashtag #Animalnation and in the Animal ... ! Join the movement!!! And be on the lookout for more from #Animalnation.

asked Mar 13, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+11 votes
0 answers 52 views Amazing Rat Tricks. More videos to come!!! Tell us how much you like this video below!

asked Mar 12, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
2 answers 893 views

5 SECRETS ZOOS DON'T WANT YOU TO KNOW Can you imagine spending your entire life in a small space that isn't big enough to do anything you enjoy doing, ... the Americas in New Orleans died after the power failed and employees were forced to leave.

asked Mar 12, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+8 votes
1 answer 254 views

SURPRISING FOODS THAT ARE POISONOUS TO DOGS AND CATS When we welcome animal companions into our families, it means making a promise to take care of them as well as ... be found in sugar-free products like gum, candy, toothpaste, and peanut butter.

asked Mar 12, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 146 views

10 THINGS TO THINK ABOUT BEFORE GETTING A HAMSTER Some parents let kids get hamsters because they think that they're good starter pets. But that's just not true. Caring for a ... live to be between 2 and 3 years old, which can be very sad. *****

asked Mar 12, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 109 views

4 THINGS PET STORES DON'T WANT YOU TO KNOW Pet stores cause countless dogs, cats, birds, rabbits, reptiles, and other animals to endure extreme pain and suffering ... the hashtag #animalnation and place in under Animal Advice Column! More to come!!!

asked Mar 12, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)
+10 votes
0 answers 58 views

asked Feb 22, 2017 in Animal Advice Column by -GEMHeart- (278,660 points)

Recent Badges

Popular Question
- #Cindystrong-Sky -
Nice Question
- jellyfishlover -
Nice Answer
- arkzo -
Nice Comment
- ArtistGirl -
Nice Answer
- WelshTerriersssCS -