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FIV: To Vaccinate or Not to Vaccinate?

FIV: To Vaccinate or Not to Vaccinate?The Feline Immunodeficiency Virus was first discovered in the year 1986 when stray cats living together in a cattery in Northern California started showing symptoms of immunodeficiency. Since the only virus known to weaken the immune function at that time was the Feline Leukemia Virus (FeLV), all cats were tested for it, but none of them got a positive test result.

They were soon able to identify that a new virus was causing the illness and initially referred to it as the Feline T-Lymphotropic Virus. However, they later changed it to Feline Immunodeficiency Virus or FIV because of how it resembles the Human Immunodeficiency Virus or HIV in humans.

In 2002, the first commercial vaccine for FIV called Fel-O-Vax® FIV was released in the US. The vaccine was then introduced to other countries, namely, Canada in 2003, Australia and New Zealand in 2004, and Japan in 2008. The vaccine was warmly welcomed by the masses, but the hype was short-lived. People began noticing the negative effects of the FIV vaccine and started advocating against it.

So, should you get your cat vaccinated against FIV? Here are five reasons why you shouldn’t.


The Prevalence of FIV Is Low

In the United States, only 1.5 to 3 percent of cats are infected with FIV. On top of that, the disease is quite difficult for cats to contract as long as proper preventative measures, such as spaying and neutering, are in place.


The FIV Vaccine Doesn’t Protect Against All Forms of FIV

There are currently five subtypes of FIV across the world: A, B, C, D, and E, and an ideal vaccine should be able to protect against all subtypes. However, that’s not the case with the FIV vaccine, which can only protect against two FIV subtypes: A and D. So, vaccinated cats will still be able to contract the virus, especially those residing in countries that are exposed to other strains of FIV.


Constant Booster Shots Increase the Risk of Sarcoma

Another thing about the FIV vaccine is that it needs to be administered on a yearly basis, which isn’t much of a problem with other vaccines. However, since the FIV vaccine is adjuvanted, meaning it contains chemical enhancers that prompt an even stronger immune response, it puts cats at risk for developing injection-site sarcomas (tumors that develop in areas where cats receive injections).


FIV Vaccination Leads to False-Positive FIV Test Results

Since FIV tests are made to detect antibodies (cells produced by the body after being exposed to a certain pathogen) and not antigens (foreign substances, such as bacteria and viruses), vaccinated cats will most likely test positive for FIV despite not having the virus.

This can be a problem for vaccinated cats that end up in shelters or somebody else’s backyard. Without a medical record, there’s no way of telling whether a cat is just vaccinated or actually infected. So, either way, they’re going to be labeled as FIV-positive, which can keep them from getting adopted, or worse, get them mistakenly euthanized.


There Are Safer Ways to Prevent the Spread of FIV

We already know that FIV is mainly transmitted to deep bite wounds. So, instead of getting cats vaccinated, it’s better to focus all our efforts on minimizing the incidence of catfights. The best way to do that is through spaying and neutering since fixed cats are less aggressive and less likely to pick fights with other cats.

It’s also best to keep house cats indoors. If that’s not an option, you can build a secure catio in your backyard where they can safely enjoy the outdoors or train them to wear a harness for supervised neighborhood strolls. That way, you’ll be able to keep an eye on them during their outdoor adventures and make sure they’re out of harm’s way.