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    Do Indoor Cats Need So Many Vaccines?
    Will Draper, DVM posted:
    In my practice, we have what we refer to as our "Wellness Form." Clients who bring their pets in for their annual or bi-annual exams are asked to fill this out. It helps us tailor a pet's vaccine, dietary and other medical needs to their particular lifestyle. This is very important when considering outdoor versus indoor cat vaccination needs. I don't believe in "over-vaccination".

    Outdoor cats are exposed to lots of viruses and other health risks that indoor cats are not. One of the biggest is Feline Leukemia Virus FELV. This airborne virus is highly contagious from cat to cat -- and therefore imperative for an outdoor cat to receive regularly. While vaccinations don't completely prevent a pet from contracting the particular disease, it makes them much less likely to come down with it -- in many cases 80% less likely.

    Indoor cats are unlikely to contract diseases like FELV, unless they live in a household with a cat that goes outdoors. In that case, the indoor cat should be vaccinated for the same things as his or her housemate. If a completely indoor cat is the sole feline, I generally do not recommend FELV vaccinations.

    When a client brings a new kitten in and we start their first vaccination series, I always recommend adding the FELV vaccine. Sometimes, as these kittens grow to be adult cats, they don't work out in that particular household and are given away to another home or taken to a shelter. It's better to protect them in case things don't work out rather than put them at risk if they do go to another home where they can potentially be converted to an outside pet.

    Another annual feline vaccination is commonly called "Feline Distemper" or " 5-in-1 Combo." It includes protection against 5 different feline respiratory, neurological, and intestinal illnesses. This is also a vaccine to consider based on lifestyle. Rabies vaccinations are required by law, and should be given regularly to all cats, regardless of indoor or outdoor status.

    Is your cat indoor or outdoor? If so, what vaccinations does your veterinarian recommend?
    Dr. Will
    ponyrun2 responded:
    As I am (now) allergic to cats (and 1 breed of dog) I am a dog person... but have worked at local vet clinics in the past....

    What do you consider a cat who has access to a screened-in porch or kitty play area ? Or even access to an open (but screened) window ? Can't an airborne virus pass through the screen ?

    With my dogs my vet's vaccination schedule (after the initial puppy vaccination series) is the rabies every 3 years, the DHLPP2 combo every other year, and a single Leptospirosis every 2 years (in the years not given the combo)... As my dogs are rarely around other dogs (unfortunately) and don't get boarded I forego the Bordetella vaccine....

    I would much rather "over vaccinate" than risk losing my dog to these preventable diseases...

    PS - and all of my dogs, especially being in SW Florida, are on heartworm prevention....
    Will Draper, DVM replied to ponyrun2's response:

    You are correct that some airborne viruses can pass through some screens. If a patient is in an area where a significant amount of stray/feral cats reside, and if there is an issue with these cats potentially hissing at one another through the screen, you could have a good argument for vaccinating against viruses like feline leukemia. However, that's the reason for vets to get a good, thorough history...and then owner and vet can make the best educated decision. If there is very little risk of being infected, there may not be a reason to give the vaccination.

    There is also those arguments stating scenarios like "What if my house is robbed, the door is left open and my cat gets out?" One could come up with lots of those "what ifs". But we all know the likelihood of something like that happening is pretty slim, and again owner and vet have to decide if the vaccination is worth giving.

    Fantastic that you keep your dogs on heartworm meds. Very important, particularly here in the south.
    Dr. Will
    Violets_are_Blue responded:
    As someone who works in a vet clinic, I vaccinate my two cats against Felv and the distemper combo yearly even though both cats are 99% indoors. I always worry what I could possibly bring home to them on my shoes and scrubs. I'm also considering adding another cat or two to our household at some point since we do get litter drop-offs sometimes. While I do plan on testing the new additions for FIV/Felv when they're old enough, it's just easier to keep them vaccinated than rush back and try to prevent a widespread infection if one turns out to be positive for Felv. While it also is possible for me to do titers on them yearly, we honestly cannot draw blood on my younger cat without sedating her (we attempted to do a simple blood screen before we cleaned her teeth a month ago and weren't even able to get the syringe near her conscious).

    Rabies vaccination is only required every 3 years in my state with the prerequisite that the pet has received 2 vaccinations 12 months to the day apart. Both of them are on the 3 year track now as well as my older Lab.
    Violets_are_Blue replied to Violets_are_Blue's response:
    I'm actually quite curious as well on what your thoughts on heartworm prevention for cats are and if you have a preferred oral prevention (Interceptor and Heartgard are the two I'm familar with). While our clinic does stock Revolution, I'm quite happy with the Frontline plus and would prefer an oral medication first.
    Will Draper, DVM replied to Violets_are_Blue's response:
    Violets: Good idea to vaccinate your indoor kitties for Felv, particularly if they go outside for even that 1%. As for transmitting Felv on your clothes...there is always that very, very slight possibility, but highly unlikely. Felv, which is what is known as a retrovirus, does not survive outside of the cat's body, in a dry environment, for more than a couple of hours (in a moist enviromnent, say a litter bowl or water dish, it has been shown to survive for up to 2 days). It is generally transmitted via feline saliva through cat bites, water bowls, shared grooming, water bowls, and litter boxes (the virus can also be present in urine). The likelihood that you'll transmit the virus to your cats from your scrubs is incredibly low. But, as you have shown, it is many times a personal choice as much as a medical one.
    Dr. Will
    Will Draper, DVM replied to Violets_are_Blue's response:
    Cats can be infected by heartworms, just as dogs can...and unfortunately there is no present treatment for cats that are infected with heartworms. Therefore I strongly recommend heartworm preventative for cats and dogs (and ferrets too) year 'round. We generally send Revolution home with our clients, because of ease of application to their cats. For those who use Frontline Plus (which I'm very happy with as well), we generally send home Interceptor for prevention against heartworms, and the intestinal parasites, hookworms and roundworms. Heartgard is also a great product for this...we just don't carry much of it in my practice. Some owners will ask for Heartgard Plus, however, and we do supply it to them through our online store.
    Dr. Will
    srstephanie responded:
    Hi Dr Draper,

    Haha! Vaccinations are one of my favorite topics! Wish I could just sit down and chat with you. I've learned a lot from CE talks by Dr Richard Ford (NCSU), Dr Mike Lappin (Colorado State), Dr Ron Schultz (Wisconsin), and Dr Margie Scherk ... all of whom are members of the AAFP Advisory Panel that wrote the 2006 AAFP Feline Vaccination Guidelines. I'm most influenced by Dr Ford after listening to about 10-12 hours of talks and attending one 4-hour session with him ... and corresponding a bit with him. He is coming to Montreal for a 3-day conference next April and I'm looking forward to seeing him. I'm on a number of lists and vaccine questions come up often with a lot of misinformation on the internet. I am still just a beginner but have tried to learn from those I trust and who know a ton more than I do.

    Just wondering, do you tailor your FeLV recommendations based on age? Dr Ford and others have stated that kittens with immature immune systems (i.e. under 8 months of age) are EXTREMELY susceptible to FeLV infection, but adult cats have a natural resistance to it and it is actually hard to infect an adult cat. He said that many experts feel that even when cats are first diagnosed with FeLV as adults, it is likely that they were infected as kittens but that the virus hid in the bone marrow cells (resulting in negative tests) for years and only caused disease as adults. The AAFP Guidelines strongly recommend that all kittens be vaccinated for FeLV (many call it "Core" for kittens) but it is considered Non-Core for adults ... i.e. only given, as you stated, if there is a known risk factor.

    When giving the the FeLV vaccine, do you use Merial's Purevax recombinant FeLV? There's a known connection between vaccine associated sarcomas (VAS) and adjuvanted Killed Virus vaccines in general, and KV FeLV and Rabies in particular. Thus, many strongly recommend the rFeLV (and rRabies) that has no adjuvant and little if any post-vaccination inflammation. Dr Ford points out that the transdermal rFeLV in the US is the only FeLV vaccine to give good Cell Mediated Immunity.

    What vaccines do you include in a "5 in one"? The usual Core vaccines are just 3 (Panleukopenia, Herpes, Calici - "FVRCP") plus Rabies. Do you add Chlamydophila? A retrospective study by Dr George Moore suggests that the risk of post-vaccine reactions increases with the number of antigens given at the same time, so my preference is not to give them all together. The AAFP Guidelines agree with you in not over-vaccinating, and they recommend the Core vaccines be boostered every 3 years (after the initial series and 1 yr booster). Most immunologists believe that with Panleukopenia, one injected Modified Live Virus vaccine as an adult will protect for life, though the Guidelines still recommend boosters every 3 years.

    My new kitten, Lisabelle, had Merial MLV FVRCP vaccines at 8, 12 and 17 weeks and her Rabies (Purevax Recombinant Rabies) at 20 weeks. Her vet will give her another FVRCP at one year after the last (i.e. this October) and then a rRabies booster three weeks later. She didn't get an FeLV. She was 22 weeks old when I got her and she is an only cat now in a 6th floor apartment near downtown Montreal ... and extremely low risk. I shared her vaccinations with Dr Ford who approved and said he would vaccinate his own the same way. He also feels that given her low risk, after the 1 yr booster, she probably doesn't ever need another vaccination (other than legal Rabies requirements). I agree with the general principle of the AAFP Guidelines ... give the vaccinations that are necessary, and no more than is necessary.

    As you stated, there is no ONE vaccination protocol and every cat's individual situation and risk factors need to be taken into account.

    Just a few thoughts.

    Stephanie in Montreal
    srstephanie replied to ponyrun2's response:
    Hi Ponyrun2,

    Just a comment on your saying you would rather "over vaccinate" than risk losing a dog.

    We compliment one another well, since I know mostly cats, where you know dogs better. I just wanted to comment that in cats, there is the added factor of Vaccine Associated Sarcomas (VAS) which are very aggressive and often fatal cancers. I know they "can" occur in dogs but are much rarer than with cats. So, with cats, there is an added incentive not to "over vaccinate". From the little I know about dogs, the smaller breeds have a much higher risk of negative post vaccination reactions, so people with small dogs may want to avoid unnecessary vaccinations.

    In cats, VAS is caused by inflammation at the vaccination site ... which, in some cats with a genetic predisposition, can lead to a mutation in the p53 gene (a tumor suppressor gene) and result in a sarcoma. It still isn't all that common, with an estimate of 1 in every 1,000 to 10,000 vaccinations ... but when it is one's own cat, that is still too frequent.

    Anything that causes inflammation in cats can lead to a sarcoma, e.g. other injections (antibiotics, insulin, even subcutaneous fluids), or even inflammation from trauma. I recently saw an abstract of an article about a cat that developed a sarcoma after a surgical sponge was accidentally left in a cat after surgery. When the tumor was removed, they found the sponge in the center. However, Killed Virus vaccines are felt by most to be the greatest risk in cats because they cause a long-term chronic inflammation at the vaccination site. So, most experts recommend avoiding Killed Virus vaccines in cats, and avoiding over vaccination in general. It requires a genetic predisposition, but it is not possible to know what cats are predisposed until they develop a VAS.

    One other aspect in cat vaccinations has to do with the cell cultures that the vaccines are grown on. Many vaccine viruses are grown on a type of feline kidney cells called "Crandell Rees Feline Kidney cells (CRFK). Minute traces of the CRFK cell culture is found in feline vaccines. Dr Mike Lappin at Colorado State Univ discovered that cats do develop antibodies to the CRFK cells, though a connection hasn't been found between the anti-CRFK antiobodies and feline kidney disease. In one study by Dr Lappin in which some cats were given injections of CRFK cells monthly for a year, then a booster one year later, some did develop kidney disease ... but no one vaccinates cats monthly. However, while Dr Lappin feels that vaccines are essentially safe and their benefits outweigh the risks ... he also recommends avoiding over vaccination in cats.

    Just sharing some thoughts.

    Stephanie in Montreal
    srstephanie replied to Violets_are_Blue's response:
    Hi Violets_are_Blue,

    Just a couple comments. Even if you were able to do titers, I'm not sure how helpful they would be. For Panleukopenia, titers DO correlate well with protection. So titers can be helpful there ... though all immunologists believe that cats that receive one injected Modified Live Virus Panleukopenia vaccine as an adult will be protected for life.

    But with the two upper respiratory viruses, Herpes and Calici, the new 2010 Vaccination Guidelines of the World Small Animal Veterinary Association (WSAVA) state:
    "It is not anticipated that a titre test for serum antibody to FCV nor FHV-1 will ever be of value in measuring vaccine immunity in the cat."

    With FeLV, there is no correlation between antibody titers and immunity ... so that there is no (the last I heard) commercial titer test for FeLV.

    Titers are also useless for FIV because currently (as far as I know) none of the FIV tests in N America can distinguish between antibody titers to the vaccine virus and those of the actual disease. I've heard there is one test in Japan that can distinguish the two, but it isn't available in N America. For that reason, many vets choose not to give FIV vaccinations. If an FIV vaccinated cat ended up in a shelter and tested positive for FIV antibodies, the cat may well be euthanized.

    With Rabies, while the titers do correspond to protection ... it is important to know that the presence of Rabies antibody titers is NOT considered proof of protection according to US LAW. If a cat or dog bites someone and the Rabies vaccine is not up-to-date, the cat/dog may be killed to check for Rabies. The legal system does not accept titers as proof of protection (even if, immunologically titers do indicate protection).

    So in cats, titers for:

    1) Panlukopenia - are indication of immunity, but most cats vaccinated as adults are considered protected for life anyway
    2) Herpes & Calici - are not indicative of immunity
    3) FeLV - are not indicative of immunity and not even available
    4) FIV - can't distinguish between immunity from the vaccine virus and actual infection
    5) Rabies - correlate with immunity but are not recognized by law, so boosters must still be given.

    So, you are probably right to just decide when you want to booster and go ahead without the titer tests.

    One other aspect of antibody titer tests that one should be aware of ... even when there is NO measurable antibodies present ... the dog/cat may STILL be protected. One of the chief functions of vaccination is to "teach" the immune system's "memory cells" so they will recognize future exposure to the antigen and produce antibodies as needed. Often, even with no titer when challenged, the memory cells will quickly "remember" the disease and produce protective antibodies. But there is no way to be certain that the memory cells will respond to a challenge, so when titers are not measurable, boosters are usually recommended.

    And a couple final comments on Rabies vaccines. Boosters (after the initial series and one year booster) must be given according to the label on the Rabies vaccine used ... either 1 or 3 years. It sounds good to use a 3 year vaccine and vaccinate less frequently, but all 3 yr Rabies vaccines are Killed Virus vaccines with a known connection to vaccine associated sarcomas (in genetically predisposed cats). KV vaccines must contain an adjuvant to stimulate the immune system to respond to a dead vaccine virus and adjuvants cause chronic inflammation which is a risk factor in VAS.

    The ONLY non-adjuvanted Rabies vaccine is the Merial Recombinant Rabies. However, it only has a 1 year label (though it is known to protect for at least 3 years). It is unknown if an annual booster with a recombinant vaccine is "safer" than every 3 years with a KV vaccine ... but most feel that it is better to avoid KV vaccines.

    As always it is a decision of risk vs benefit.

    ponyrun2 replied to srstephanie's response:
    But isn't the issue with the sarcomas is that it could happen with any vaccine regardless of how many vaccines are given ?

    For example, say you only gave your pet the law required rabies vaccine... if your pet is sensitive to the vaccines wouldn't your pet have the same chance of getting the sarcoma as another sensitive pet who receives all of the other vaccines ?

    I hope what I'm trying to ask makes sense.....
    Violets_are_Blue replied to srstephanie's response:
    That is really interesting on the titers. I do wonder if the U.S. will start allowing titers as I know a few other countries require a titer test for rabies and tell the owner after the results if the pet needs to be re-vaccinated or not.

    With the KV vaccines, would there be less risk if the vaccine is used every 3 years following the yearly booster or yearly? Our clinic honestly cannot carry 2 different rabies vaccination because of space issues which is the reason I'm asking. It would seem using less of the same vaccine would be safer (for example, a 15 year old cat receiving 6 KV rabies vaccinations versus 15 vaccinations).
    Will Draper, DVM replied to srstephanie's response:
    Stephanie...I am not surprised in the least bit to learn of your knowledge of vaccines and protocols...again, when are you moving to Atlanta? .

    We do use the Merial Purevax FELV vaccine. The non-adjuvanted nature does lend to fewer reactions, such as the vaccine asscoc. sarcomas you mentioned to ponyrun2. I do recommend this vaccination to kittens in the last 2 parts of their kitten vaccination series. Since the purpose of vaccinations is to "trick" the body into thinking there is some threat, therefore making it produce antibodies to protect itself from said threat, it is important to make sure the patient's immune system has developed some. Also, I recommend it to kittens because many times that kitten does not work out in the household and may go to a new home- where they may be an outside instead of inside cat. It's better to have the vaccination on board in that case- even if it is not considered a "core vaccine". As for Lisabelle, I'd bet just about anything that there is nothing that would lead you to "re-home" her like some less-dedicated feline owners might do (i.e. scratching furniture, marking in the home, etc.). So, your choice not to vaccinate her against Felv is one I would support completely. Again, the protocol followed should be designed with both the patient and owner in mind.

    I mentioned "5-in-one" distemper vaccine because that's what a lot of my clients refer to the feline distemper vaccine as- because it's what they've heard it called throughout their pet-owning lives. We also use Merial Purevax Feline Distemper vaccine, which, as you noted, protects against 3 viruses: herpes virus (also referred to as feline rhinotracheitis virus), calici virus, and panleukopenia (or distemper) virus.
    Dr. Will
    Will Draper, DVM replied to Violets_are_Blue's response:
    Violet- because of the fact that some titers have not been proven to assure that the patient in question is totally protected, it may be a very, very long time before we see that sort of approval in the U.S.

    As for KV vaccines and the safety factor (giving KV every 3 yrs as opposed to recombinant, non-adjuvanted rabies), the latter annually is generally safer than the KV rabies given every 3 years in relation to the potential of VAS. We only given the Purevax Rabies (and Felv) in my practices.
    Dr. Will
    Will Draper, DVM replied to ponyrun2's response:
    Ponyrun2- it would depend on the vaccine given. If it is a non-adjuvanted one (like the Purevax Rabies), the likelihood of VAS is much lower than if it were a KV vaccine. In the latter case, if your pet is sensitive to the vaccines (or, as Stephanie noted, "genetically predisposed") I would say that the risk is less if you're giving only the law-required rabies as opposed to all vaccines.

    (I hope I understood the question and made sense myself...)
    Dr. Will

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