Feline Immunodeficiency Virus Vaccine
The vaccine is an inactivated feline immunodeficiency virus, with an adjuvant to elicit an immune response. Vaccinated cats will produce antibodies against this inactivated virus. The inactivated vaccine does NOT produce infection.
Current studies have found the vaccine to be about 82% effective in preventing infection of FIV (which I am told is reasonably good for a first round of studies).
Vaccine regimen
Initially 3 vaccinations 2-4 weeks apart followed by a booster vaccination annually to ensure optimal immunity.
Should I vaccinate my cat?
Since FIV is mainly transmitted from biting from fighting cats, any cat that goes outdoors and regularly gets into fights (with strange or stray cats) should be vaccinated. Prevention of infection though is also stressed. If you can keep your cat indoors and limit his/her exposure to cats, then the vaccine shouldn’t be necessary.
Generally in multiple cat households there is the occasional “argument’ between cats. These fights aren’t usually violent enough to cause the skin lacerations for the transmission of the virus.
Side effects of the vaccine
Pain at vaccination site
lethargy, inappetance, depression
These are usually transient and subside over 24-48 hours.
As with any introduced drug or chemical, anaphylaxis can occur and may require antihistamine or adrenaline therapy.
Locally, there may be thickening of the subcutaneous tissue and some pain.
Although there is limited information for the FIV vaccine, vaccines with an adjuvant have been known to cause vaccine site sarcomas. Though rare, any killed or inactivated vaccine with adjuvant may produce this tumour years down the track.
FIV vaccinated cats and FIV positive cats
It is worth noting the in-clinic tests available for detecting FIV positive cats uses the detection of antibodies against FIV rather than actual FIV isolation. Cats that have been vaccinated, will test positive for FIV antibodies as will cats with FIV infection. In many animal refuges, a stray cat testing positive for FIV is immediately euthanased. To overcome this problem it is recommended all cats vaccinated against FIV also be microchipped as a means of permanent identification. Cats who test positive for FIV antibodies should have samples sent to the laboratory for virus isolation.
What if my cat has FIV?
Cats with FIV do not always succumb to feline AIDS. It is important, though to ensure your cat stays away from other cats, preferably kept indoors. Regular health checks are necessary to pick up minor infections (especially oral lesions) and to assess the cat’s general well-being. Other cats in the household can be vaccinated (after testing negative) to prevent the spread of infection.
Ok..this was typed up really quickly so if something isn’t explained well enough or anyone has any questions please feel free to leave them in the comment section.
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The vaccine only covers specific clades, and it is very hard to find labs that will establish what clades you are dealing with, as in our case where we took a positive, and neuron damaged cat into our home. According to the following study, the clades covered in the vaccine are not in our area, so are useless to the rest of our cats.
http://www.bentham.org/chivr1-1/burkhard/burkhard.htm
If the cat is not aggressive, and resides with other non aggressive cats, it can live naturally with other cats, with no problem, but will be vulnerable to opportunistic diseases if the cats are allowed outdoors.
I don’t have the site handy, however, the AVMA has come out with a statement suggesting the vaccine should not be used, and Marvistavet, which is a reliable internet source of information, had the following statement up on their site long before the AVMA took a stand. http://www.marvistavet.com/html/fiv_vaccine.html