- Feline immunodeficiency virus
Taxobox
name = "Feline immunodeficiency virus"
virus_group = vi
familia = "Retroviridae "
subfamilia = "Orthoretrovirinae"
genus = "Lentivirus "
species = "Feline immunodeficiency virus""Feline immunodeficiency virus" (FIV), occasionally referred to as "Feline or Cat AIDS" is a
lentivirus that affects domesticated housecats worldwide. Approximately 11% [cite journal| doi = 10.1016/j.biologicals.2005.08.004| title = Feline immunodeficiency virus vaccine: Implications for diagnostic testing and disease management| year = 2005| author = Richards, J| journal = Biologicals| volume = 33| pages = 215 ] of cats worldwide, and about 2.5% of cats in the USA, [ cite journal| doi = 10.1016/j.biologicals.2005.08.012| title = Feline immunodeficiency virus vaccine: A rational paradigm for clinical decision-making| year = 2005| author = Zislin, A| journal = Biologicals| volume = 33| pages = 219] are infected with FIV. More than 90% of African lions in some zoos tested positive for the virus. FIV differs taxonomically from two other feline retroviruses, feline leukemia virus (FeLV) and feline foamy virus (FFV). Within FIV, five subtypes have been identified based on amino acid sequence differences coding for the viral envelope. FIV is not a death sentence for cats, as they can live relatively healthy as carriers and transmitters of the disease for many years. A vaccine is available although its efficiency remains uncertain, and cats will test positive for FIV after vaccination. [ [http://www.aafponline.org/resources/statements/felovax.htm Statement on Felovax] at www.aafponline.org]FIV was first discovered in 1986 in a colony of cats that had a high prevalence of opportunistic infections and degenerative conditions, and has since been identified as an endemic
disease in domestic cat populations worldwide [ cite journal| doi = 10.1016/j.biologicals.2005.08.012| title = Feline immunodeficiency virus vaccine: A rational paradigm for clinical decision-making| year = 2005| author = Zislin, A| journal = Biologicals| volume = 33| pages = 219] .Transmission
The primary modes of FIV transmission are deep bite wounds and scratches, where the infected cat's saliva enters the other cat's bloodstream. FIV may also be transmitted from pregnant females to their offspring in utero. It must be noted that such claims that FIV is transmittable by simply "touching noses" have been discreditedFact|date=September 2008.
This differs from
FeLV , which may be spread by more casual, non-aggressive contact, such as petting, 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 cause.Therefore, FeLV (feline leukemia virus) is often known as a "friendly cat disease" whereas FIV (feline immunodeficiency virus) is known as an "unfriendly cat disease."
Testing
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". Therefore, a positive test does not necessarily mean the cat is a carrier of FIV.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 life due 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 criteria foreuthanasia . [ [http://www.aafponline.org/resources/statements/felovax.htm Statement on Felovax] at www.aafponline.org]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. [KittyTest.com. http://www.kittytest.com/fiv.jsp]
The [http://www.catvets.com/ American Association of Feline Practitioners] , an organization of veterinarians with a special interest in the health of cats, urges regular testing but not euthanasia of infected cats. Infected cats can live for years if diagnosed early and managed properly.
Vaccine
A vaccine for FIV is available, and was developed using isolates of two of the five FIV subtypes (or clades): A and D. [Citation | doi = 10.1016/j.jfms.2008.03.002| title = 2008 American Association of Feline Practitioners' feline retrovirus management guidelines| year = 2008| author = Levy, J| journal = Journal of Feline Medicine & Surgery| volume = 10| pages = 300] The vaccine was shown to be moderately protective (82% of cats were protected) against subtype A FIV, [Citation | last1 = Huang | first1 = C. | last2 = Conlee | first2 = D. | last3 = Loop | first3 = J. | last4 = Champ | first4 = D. | last5 = Gill | first5 = M. | last6 = Chu | first6 = H.J. | year = 2004 | title = Efficacy and safety of a feline immunodeficiency virus vaccine | journal = Animal Health Research Reviews | volume = 5 | pages = 295-300 | doi = 10.1079/AHR200487] but a later study showed it to offer no protection against subtype A. [Citation | last1 = Dunham | first1 = S.P. | last2 = Bruce | first2 = J. |last3 = Mackay | first3 = S. | last4 = Golder | first4 = M. |last5 = Jarrett | first5 = O. | last6 = Neil | first6 = J.C. | year = 2006 | title = Limited efficacy of an inactivated feline immunodeficiency virus vaccine. | journal = Veterinary Record | volume = 158 | pages 561-562] It has shown 100% effectiveness against two different subtype B FIV strains. [Citation | last1 = Kusuhara | first1 = H. | last2 = Hohdatsu | first2 = T. | last3 = Okumura | first3 = M. | last4 = Sato | first4 = K. | last5 = Suzuki | first5 = Y. | last6 = Motokawa | first6 = K. | last7 = Gemma | first7 = T. | last8 = Watanabe | first8 = R. | last9 = Huang | first9 = C. | last10 = Arai | first10 = S. | last11 = Koyama | first11 = H. | year = 2005 | title = Dual-subtype vaccine (Fel-O-Vax FIV) protects cats against contact challenge with heterologous subtype B FIV infected cats. | journal = Veterinary Microbiology | volume = 108 | pages = 155-165 | doi = 10.1016/j.vetmic.2005.02.014 ] [Citation | last1 = Pu | first1 = R. | last2 = Coleman | first2 = J. | last3 = Coisman | first3 = J. | last4 = Sato | first4 = E. | last5 = Tanabe | first5 = T. | last6 = Arai | first6 = M. | last7 = Yamamoto | first7 = JK. | year = 2005 | title = Dual-subtype FIV vaccine (Fel-O-Vax FIV) protection against a heterologous subtype B FIV isolate. | journal = Journal of Feline Medicine and Surgery | volume = 7 | pages = 65-70] 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. [Citation | doi = 10.1016/j.jfms.2008.03.002| title = 2008 American Association of Feline Practitioners' feline retrovirus management guidelines| year = 2008| author = Levy, J| journal = Journal of Feline Medicine & Surgery| volume = 10| pages = 300-316]
Approved Treatment
In 2006, the
United States Department of Agriculture issued a conditional license for a new treatment aid termedLymphocyte T-Cell Immune Modulator [United States Department of Agriculture. Veterinary Biological Products; Licensees and Permittees, December 2006. [http://www.aphis.usda.gov/vs/cvb/RegsGuidance/CurrentProdCodeBook.pdf] ] . Lymphocyte T-Cell Immune Modulator is manufactured by T-Cyte Therapeutics, Inc. and sold by IMULAN BioTherapeutics, LLC.Lymphocyte T-Cell Immune Modulator 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 oflymphocytopenia ,opportunistic infection ,anemia ,granulocytopenia , orthrombocytopenia . The absence of any observed adverse events in several animal species, suggests that the product has a very low toxicity profile.Lymphocyte T-Cell Immune Modulator is a potent regulator of CD-4
lymphocyte production and function. [Beardsley, et al. "Induction of T-Cell Maturation by a Cloned Line of Thymic Epithelium (TEPI) Immunology 80: pp. 6005-6009, (Oct. 1983). ] It has been shown to increase lymphocyte numbers andInterleukin 2 production in animals. [Beardsley, Terry R. Patent # 7,196,060; Method to enhance hematopoiesis. [http://www.google.com/patents?id=wE1_AAAAEBAJ&dq=7,196,060 Method to enhance hematopoiesis - Google Patents ] at www.google.com] Lymphocyte T-Cell Immune Modulator is a single chainpolypeptide . It is a strongly cationicglycoprotein , and is purified with cation exchange resin. Purification of protein from bovine-derivedstromal 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. [Beardsley, Terry R. Patent # 5,616,554; Immune-enhancing agent for therapeutic use in immunocompromised hosts. [http://www.google.com/patents?id=TXMbAAAAEBAJ&dq=5,616,554 Immune-enhancing agent for ... - Google Patents ] at www.google.com]Other Unapproved Treatments
FIV TREATMENT(Probably helps with FELV too)Helps strengthen immune system to fight the virus. Enables FIV cat to live longer. The effect likely to vary depending on state of cat’s immune system and present disease progression. As with most treatments, start as early as you can in the disease progression. Cellular Forte Max Inositol Hexaphosphate (IP6) Capsules Inositol Hexaphosphate (IP-6) is derived from soybeans, rice, sesame seeds, beans, legumes and cereals. IP-6 is a polysaccharide (long-chain sugar) found in fiber that has anti-oxidants. Agaricus Bio Capsules for Dogs and Cats Contains Beta Glucans from the Agaricus blasei mushroom. Beta glucans have the ability to stimulate macrophage activity which could help reduce the impact of viruses, bacteria and malignant cells. The proper does is 300 mg/day in one dose. Agaricus LiquidLiquid form of Agaricus Bio. The dosage is One drop per pound/day. Milk ThistleHelps prevent depletion of glutathione, raises glutathione levels up to 35 percent and protects the liver from damage. It can be used in pets on chemotherapy to help the liver process and detoxify drugs. T-CyteTerry Beardsley, Ph.D., is the researcher and the driving force behind this recently FDA approved product. The active protein in this injectable product serves as a growth factor to restore lymphocytes which are depressed by retroviral infections.
Effects
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, neither can infect the other's usual host: humans cannot be infected by FIV nor can cats be infected by HIV. FIV is transmitted primarily through saliva (bites), 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.
Consensus whether there is a need to euthanize FIV infected cats has not been established, although this is a pragmatic approach towards protecting the general population and is a wise option for cats testing positive turned in to animal shelters. The American Associations of Feline Practitioners, as well as many feral cat organizations, recommend against euthanizing FIV+ cats, or even spending funds to test for the virus, as spaying or neutering cats seems to effectively control transmission - as neutered cats are less likely to engage in territorial fights. A vigilant pet owner who treats secondary infections can assist an infected cat 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 Harv|American Association of Feline Practitioners|2002. 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 not non-existent risk.
The disease occurs in three stages: First is the Acute Stage (1-2 months after transmission) in which fever, depression, and generalized
lymphadenopathy are observed Harv|Wise|2005. Second is the Subclinical Stage (4 weeks to X months after transmission), in which symptoms of the disease decrease or disappear; however, all cats remain viremic for life. Third is the Chronic Stage, in which cats eventually succumb to chronic infections due to suppressed immune system function. Cats may incurstomatitis ,odontoclasia ,periodontitis ,gingivitis ,rhinitis ,conjunctivitis ,pneumonitis ,enteritis , anddermatitis in the later stages of infection. FIV+ cats are less likely to develop AIDS-like symptoms than HIV+ humans.FIV infects other feline species, and in fact is endemic in some large wild cats, such as
Africa nlion s. Unlike domestic cats, these species do not necessarily exhibit symptoms, perhaps because they have developedevolution arymutation s that confer resistance.See also
*
Feline vaccination References
*Harvard reference | last=American Association of Feline Practitioners | first= | authorlink= | year=2002 | title=Feline Immunodeficiency Virus | periodical= | volume= | issue= | pages=| url=http://www.vet.cornell.edu/fhc/brochures/fiv.html | access-date=2006-01-23
*Harvard reference | last=Johnson | first= | authorlink= | year=2005 | title=Proceedings | periodical= | volume= | issue= | pages=| url=http://www.ivis.org/proceedings/acvp/2005/Johnson/chapter.asp?LA=1 | access-date=
*Harvard reference | last=Might | first=Jennifer Lynne | authorlink= | year=2004 | title=Feline Immunodeficiency Virus (FIV) | periodical= | volume= | issue= | pages=| url=http://www.blackgiraffe.com/jmight/fiv/fiv.html| access-date=2006-01-23
*Harvard reference | last=Wise | first= | authorlink= | year=2005 | title=Chapter | periodical= | volume= | issue= | pages=| url=http://www.ivis.org/advances/carter/Part2Chap15/chapter.asp?LA=1#fel_immuno | access-date=
*Harvard reference | last=American Association of Feline Practitioners | first= | authorlink= | year=2005 | title=AAFP guidelines on FIV and FeLV | periodical= | volume= | issue= | pages=| url=http://www.aafponline.org/resources/guidelines/Felv_FIV_Guidelines.pdf | access-date=2008-07-22
*Harvard reference | last=The Lion Research Center | first= | authorlink= | year=2005 | title=FIV in African Lions| periodical= | volume= | issue= | pages=| url=http://www.lionresearch.org/current_docs/fiv.html | access-date=2008-07-22
*Harvard reference | last=Alley Cat Allies| first= | authorlink= | year=2001 | title=Should we release FIV+ cats? | periodical= | volume= | issue= | pages=| url=http://www.alleycat.org/pdf/shouldwerelease.pdf | access-date=2008-07-22External links
* [http://www.thepurrcompany.com/cat-articles/feline-immunodeficiency-virus-(FIV).php An article on FIV]
* [http://www.imulan.com/felv-fiv-treatment.html Lymphocyte T-Cell Immunomodulator (LTCI)]
* [http://www.kittytest.com/ KittyTest.com, a site where cat owners can check the prevalence of FIV and other feline diseases in their areas]
* [http://www.lionresearch.org/current_docs/fiv.html FIV in lions]
* [http://www.aafponline.org/resources/guidelines/Felv_FIV_Guidelines.pdf American Association of Feline Practitioners guidelines on FeLV and FIV]
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