Dog Vaccines and Vaccinations


Dog Vaccines and Vaccinations

Vaccination protocol update

Subscriber Question: Have been receiving info from different sources that the veterinarian schools are in the process of changing the protocol for vaccinating. All the information I've received states that vaccinations should be less frequent but they don't all give the same agenda. What is the proper protocol? I'm under the impression that adult dogs do not need yearly vaccinations and that rabies vaccines need be given only every three years. Also that in most cases Lepto and corona vaccines are not necessary. I must admit that I have not been giving either of these vaccines to my dogs for several years due to bad reactions in the past. Thank you, Jan

Answer: Jan- At the present time there is no universally accepted vaccination protocol for dogs or cats. Veterinarians are really divided over the best way to vaccinate.

These are the main camps:

1) Vets who think that vaccinations should be given every year. Their logic: a) The labels say to do that and following label directions lessens liability. b) There isn't much published information in refereed (scientifically reviewed) journals that refutes the once yearly vaccination schedule. c) It is the way things have always been done and there is an obvious decrease in distemper, parvovirus, etc, so why stop something that is working? d) Bacterial vaccines (leptospirosis, Bordetellosis, possibly Lyme disease) are not noted for long term protection -- they may not even provide a year's protection --- so these vaccines may be necessary yearly or more often if they are necessary in a particular area.

2) Vets who think that vaccines should be extended to every three years. Their logic: a) It is obvious that some dogs react badly to vaccinations, either at the time they are given or several weeks later by experiencing immune mediated hemolytic anemia (IMHA). There is a documented rise in the cases of IMHA for the month following vaccination in dogs but it is a slight rise -- just barely enough to be statistically significant. Therefore, it seems important to give vaccinations only as often as is necessary. b) There isn't enough information to tell how long vaccines really last (see b above) BUT it seems pretty obvious they last longer than one year -- so every three years seems like a reasonable bet. It is likely the vaccines last that long just based on clinical experience alone and it cuts down some on the reactions to extend the interval to every three years. c) The veterinary schools and organizations have settled on every three years as a good compromise between what is known and not known, for the most part, so there is support for this approach in the literature, making it fairly safe from a liability standpoint. d) The duration of immunity provided by vaccinations probably varies from one vaccine to the next, depending on the strain of virus/bacteria used, the adjuvents used in the vaccine and the production methods -- therefore, until each vaccine is tested for duration of action, it will be hard to make blanket judgments about how long vaccine intervals should be.

3) Vets who think that it is OK to go to much longer vaccination intervals based on the available information which is primarily derived from unpublished studies that have been widely publicized at meetings and other information sources, but who believe strongly in the value of vaccination. Their logic: a) This information can be found despite its non-published status. The researchers are respectable within the profession. b) It is highly likely that parvovirus vaccine provides lifelong immunity and that distemper vaccine provides protection for more 5 to 7 years. It is reasonable to assume that other vaccinations for viral illnesses work as well. c) Vaccines can cause harm. Therefore, the individual risk to a particular illness AND of the vaccine should be compared for each individual patient and a vaccine schedule designed to fit the patient's needs. By doing this, the veterinarian is serving the best interest of the patient. With this in mind -- there will always be room for controversy about vaccine intervals if the logic of this argument is persuasive -- but it still could work out to be the best approach for most patients. d) Liability arguments don't seem to have much effect on this group of vets but that might change if pets are accorded a status somewhere between property and humans and things like "pain and suffering" are allowed in law suits concerning pets. Currently, this isn't the case in most states but is being considered in several localities.

4) Vets who think that all vaccines are bad. I have to admit that I can't come up with any good logical reasons for vets to think this way, so it is hard for me to provide the logic that these vets use, unless it is simply that they have experienced some bad reactions and haven't been through a parvovirus, distemper, leptospirosis, etc. epidemic in their practice area. With all this in mind, this is what I do for my canine patients: I stick to a mostly every three year vaccination schedule for the rabies (after the initial one year vaccine) and DA2PP (distemper, parvovirus, adenovirus and parainfluenza) vaccine. I don't use coronavirus vaccine, leptospirosis (but I would as soon as I see enough cases to convince me it was a problem in my area), Lyme disease vaccine (probably would use this if I saw lots of cases but I'm not sure -- fortunately, I haven't had to make this decision) or giardia vaccine. I advise using Bordetella (kennel cough) vaccine on an "as needed basis", basically prior to boarding or for dogs that go to lots of shows or other events where there are other dogs. When a dog reacts badly to the DA2PP combination vaccine and they have had at least the puppy series and one booster, I just don't give it again. I figure the risk to that individual from the vaccine probably exceeds the risk of the diseases during their lifetime (at least where I practice). If there are reactions to the rabies vaccine we pre-treat with antihistamines or corticosteroids and just give the vaccine, because it is required by law and because the risk to the dog of not being vaccinated is high --- not only from rabies but from the public health laws if it bites someone and isn't properly vaccinated. In Virginia, fortunately, 3 year duration vaccines are accepted for rabies protection. As long as the vaccine is being boostered instead of being given for the first time, corticosteroids do not cause significant interference with the production of an immune response to the vaccine. You didn't really ask about cats, but this is how we handle cat vaccinations: We give the kitten series for RCP (rhinotracheitis ( or feline herpes) , calcivirus and panleukopenia (feline distemper)) and rabies at >12 weeks of age. We vaccinate for feline leukemia in kittens, unless the owner is certain that the kitten will be an indoor only cat and there is little chance for contact with other cats who might carry the disease. We don't use any other vaccines at the present time. We booster the vaccinations that seemed necessary at one year of age. At this point we go to an every three year schedule for RCP and rabies but we don't give feline leukemia vaccination to cats again. Our logic is that most studies show that cats have a strong natural resistance to feline leukemia after they are about 18 months old, so vaccination doesn't seem warranted given the risk of vaccine associated sarcoma (cancer) in cats and the low risk of acquiring the infection as an adult. This is probably the most controversial decision we make about vaccinations (stopping the FeLV vaccine). We use the every three year rabies vaccines but it is possible to make a very good case for using PureVax (tm, Merial) rabies vaccine, which is thought to be less likely to cause cancer at vaccine sites. PureVax has to be given yearly as it is only approved for one year use. One thing you have to remember about our vaccine protocol is that we developed it for our area. We live in a very rural community and we don't have dog parks or limited areas that lots of dogs play in --- we have mostly stay at home dogs who interact with a few dogs in their neighborhood. Our cat patients may also be less likely to interact with lots of other cats compared to suburban or urban cats, as well. So we made our vaccine protocol decisions with this situation in mind. Other vets have to make their decisions based on different circumstances that influence their decision making about the risks and benefits of specific vaccines in their practice area. I hope that this was helpful. Mike Richards, DVM 8/6/2003

Revising Vaccination Schedules

Question: I recently read an article written by a vet that reported that annual pet vaccinations may NOT be necessary and could cause problems. He further reported there is a test called TiterChek (for dogs) that can show if they are already immune against life threatening diseases. What is your opinion? My 2 dogs are ages 14 and 8. Thank You Sherrie

Answer: Sherrie- I don't think that annual vaccinations are necessary (hopefully that was clear in the latest newsletter). I do think that it is important to effectively vaccinate puppies and kittens and to booster these vaccinations a year later, then to go to longer intervals if desired. We currently use an every three year schedule for most vaccinations in our practice and we use an "as needed" schedule for less effective vaccinations such as Bordetella (kennel cough) and leptospirosis. I don't think that checking titers is worthwhile, either, though. There are two problems with titer checks. The first is that the immune system is a complex system which relies on several different methods of attacking viruses and bacteria. Antibody production and maintenance is just one part of the system. It is entirely possible for a dog or cat to have a 0 titer to a virus, but to be protected well against infection by the virus. In addition, it is possible for a pet to have a strong titer -- even a very strong titer like 1:3200 and to be unprotected against a virus because the particular virus is controlled by cellular immunity or mechanisms other than antibodies. The best that we can do right now, for determining the interval that is necessary between vaccinations is to use data generated in challenge tests (where a vaccinated dog or cat is exposed to the actual virus after vaccination, at various intervals, until it becomes infected). These give us a good idea of the average duration of protection in a group. Then we decide how much risk we want to take (how close to the average we want to push the interval) and set up guidelines. This isn't a perfect approach either, but it is cost effective and it should provide good "herd" immunity --- keeping enough pets vaccinated to break the spread of a virus in a community. This is going to be a controversial subject for some time in veterinary medicine, so expect to hear a lot of conflicting information until the profession comes back to some consensus on the best way to handle vaccinations. Mike Richards, DVM 12/01/2002

Vaccination protocols for boarding facilities

Question: having waded through a multitude of e papers, I am still at a loss at to vaccination protocol's when taking a dog into a boarding establishment. I operate a very strict policy on no vaccination no boarding. but........ rural vets tend to think people do not need holidays and therefore do not vaccinate dogs against bordotella as a matter of is the dilemma...... just exactly when can we accept dogs for boarding if we require them to have been vaccinated???????????? instantly?, after what period?, or yes you had shots last year and are not fully expired so that is fine???, also....our vet sanction's 9mths for bordetalla...what is the formal reconing, as every vet is different???????????? I would appreciate some continuity in the matter as I loose out on thousands every year because I am bemused!!!!!!!!!.. sorry ...I really need some clarification on this matter, as xmas is coming and I need to ensure all vaccinations are up to date and the information I give is correct..... I will appreciate your reply Dr. .Lovie

Answer: Dr. Lovie- There isn't a consensus of opinion among veterinarians about many of the details of vaccination because much of the information concerning the duration of immunity, effectiveness of vaccines and risk of exposure is either new enough to be unsubstantiated through additional studies or of questionable value beyond the region or scope of the original study. However, there are a few things that are reasonably certain that might benefit someone trying to make decisions about requiring vaccinations for kenneling. The vaccine information is partially obtained from the AVMA's Council on Biologic and Therapeutic Agents (AVMA Journal, Nov. 15, 2002) The first question that you have to think about is whether you are trying to protect yourself against lawsuits, customer dissatisfaction and other problems or whether you are trying to protect the pets being boarded against acquiring diseases at your facility. There is a big difference in these philosophies and thus a big difference in what you might require between them. The initial questions to think about are: What are the things that dogs and cats being kenneled most likely to be exposed to? How do you prevent exposure? If you can't prevent exposure will vaccination protect the pets? Dogs in kennels are most at risk from distemper, parvovirus, bordetellosis and parainfluenza. Rabies is unlikely but the disease is so devastating that all pets should be adequately vaccinated against it in the U.S -- but I don't know if that is the case in New Zealand. Distemper, parainfluenza and bordetella are potentially airborne pathogens. They are probably more commonly spread from dog to dog by allowing contact or by using cleaning rags that are not disinfected adequately between cages. This is a good reason to use paper towels and to throw them out after single use. Parainfluenza vaccination is considered to be of low effectiveness if given by injection and moderate effectiveness when given intranasally. Parainfluenza is usually a mild infection. Distemper vaccination after twelve weeks of age is very effective. Bordetella vaccination is moderately effective by intranasal route and less effective by injection. The duration of protection varies but is lost by 6 months in some dogs and lasts 9 months or more in others. Since this vaccine does not reliably last a year it makes more sense to vaccinate dogs approximately 2 weeks prior to boarding for maximum effectiveness and to repeat the vaccination at 6 month intervals in dogs who are frequently boarded or frequently exposed to other dogs, such as at shows or working events. Parvovirus is shed through the feces and is a durable virus. It is extremely difficult to prevent contamination of premises with high transient dog populations. You should probably assume that all dogs that come to the kennel will be exposed to this virus. Immunity can not be assumed during the puppy vaccination series until approximately 2 weeks after using a high titer vaccine at 12 weeks of age or a lower titer vaccine at 16 weeks of age PLUS a 5 day to 14 day period to allow the immune system to respond. Therefore, there is substantial risk of an infection occurring at your kennel if you board puppies less than 14 weeks of age, regardless of their vaccination status. Once a successful vaccine response occurs it becomes very unlikely that a puppy or dog will ever be ill with parvovirus since there is a strong natural immunity to clinical disease in dogs over 1.5 years of age and the duration of protection from the vaccine is probably > 5yrs. With these things in mind, I would not want to board puppies less than 14 weeks of age or who have not been vaccinated after twelve weeks of age and at least 2 weeks prior to boarding for distemper and parvovirus. If you have to board puppies keep them confined to a cage or run that you can effectively disinfect between boarders. I would consider vaccination against Bordetella optional, personally -- because it is going to be real pain if you insist that it be done correctly and because the efficacy of the vaccine is thought to be moderate. But if I was going to require it I would want dogs to have been vaccinated at least 2 weeks prior to arrival and no more than 6 months prior to boarding. This disease is usually mild but it is a pain for kennels in that it is upsetting to customers. Cats are most susceptible to exposure to herpes virus (rhinotracheitis), calicivirus and panleukopenia (pretty rare in the U.S. currently). Feline coronavirus exposure is possible. Feline immunodeficiency virus and feline leukemia virus exposure shouldn't occur unless you allow boarding cats to intermingle. This is also true for rabies but again risk of exposure to you, your staff and other pets to a disease with the public health risk associated with rabies justifies requiring vaccination in the U.S. (I have no idea what the situation is in New Zealand). Feline herpes virus and calicivirus have long been thought to be airborne pathogens but again are probably most likely to be spread by contact with objects that virus has contaminated. So again, using paper towels to clean cages and throwing them out between pets is often a very effective way to prevent transmission between cats in cages or confined spaces. Washing your hands between cage cleanings is also a good idea. Feline immunodeficiency virus is spread through bite wounds primarily. That shouldn't be happening unless you allow cats to intermingle. Feline leukemia virus requires direct contact and exchange of body fluid to be spread. Feline coronavirus causes mild diarrhea in most instances but when it mutates it causes FIP (a comparatively rare event). However, good sanitation is the only defense and should be practiced. Vaccination against FIP is of questionable value and should not be required by boarding facilities, in my opinion. Vaccination against panleukopenia (feline distemper) is very effective with the same guidelines as vaccination for dogs. It is less common than canine distemper in the U.S. and lot less common than canine parvovirus. Vaccination against feline herpes virus and calcivirus does not prevent infection but does lessen clinical signs significantly and could prevent major headaches for a kennel owner since these diseases are really irritating both to cats and cat owners. It wouldn't matter to me if cats were vaccinated against FIV or FeLV, unless I was going to allow them to have contact with one another. If this was the case I would consider requiring the FeLV vaccination and might consider FIV vaccination ( this is a brand new vaccine in the U.S. and so I am hesitant to endorse it before it has been used a while and any side effects have become apparent). On the differing recommendations among vets for bordetella (and probably the other viruses and bacteria) --- to some extent recommendations are based on who the vet believes. The vaccine manufacturers claim one year duration for many of the bordetella vaccines but other studies don't support this claim. So do you believe the vaccine label or the other studies? I tend to lean towards the results of studies not funded by the company but lots of people are comfortable believing label claims. I hope this helps some. Mike Richards, DVM 12/7/02

Yearly vaccination rethinking

Question: Mike, Thanks for the advice about the ear treatment. Tuesday, 10/24 will be the fourth of the 5 prescribed treatments, and there is some improvement, but still symptomatic. Also, I am not certain that all nine dogs are shaking their heads, so I will have to pay closer attention. As to Bear's white hairs, Buddy just turned four and not a white hair on him; Sheila died before her fourth birthday, and not a white hair on her; and the littermates, 18 months old, have no white hairs. Bear's white hairs are in places where I remember there were staples, so I am afraid it is from the scarring. Oh, well, it will serve as a constant reminder for me to prevent fighting at any cost, and also, I think a few white hairs is attractive in men;) I plan to work with a professional trainer after we move, and I asked her about vet care in our new area, and wow, she is a high powered lady! She has a few of my quirks, but exponentially and *much* better informed. She says her standards for vet care are exceedingly high and she is not satisfied with anyone local. She owns the leading vet manuals, and spares no expense. She says she is a nut case when one of her animals gets sick. She gets second opinions from national experts, and that vets either love or hate her. Anyway, she raised a whole new question for me: She says she has reservations about her vet's practice of yearly vaccinations, unless the owner requests some other schedule (which she does). For technical facilities, she recommends a place with state of the art equipment and a particular vet there, and says they do not recommend yearly vaccinations after immunization titers are established. What is this all about? I have a feeling I need to learn more about this, as, presently the plan is for Dr. come to our new home to vaccinate all the dogs every year. I sure would like to have your opinion on this, plus any recommended reading for me. Thanks very much. Helen

Answer: Helen- It is reasonably certain at this time that distemper and parvovirus vaccinations have a duration of effect of at least three years and probably closer to five years, with the probability that at least some dogs have lifelong immunity after the initial vaccination series and the one year booster. The adenovirus portion of the vaccine is also reported to have a long duration of immunity and I am not certain about parainfluenza but I also do not consider this to be a very important virus to protect against. So, at the present time we are in the process of deciding what vaccine interval we will use for dogs over the next few years. I do not see much value in running titers to assess the immune system status against the various viral illnesses which there are vaccines for. High titers are not necessarily a sure sign of protection and low, or even absent titers, do not mean that there is not protection remaining due to the presence of active memory cells still programmed to recognize the virus the vaccine is supposed to protect against. The best test to determine immunity is a virus challenge but nobody in their right mind wants to use this standard to determine the protection for their individual pet. So at present, I think that the best approach is to use a reasonable time interval between vaccinations based on available information on duration of immunity. We will probably go to three year intervals in our practice, as a reasonable compromise between yearly vaccinations, which do not seem necessary, and taking the risk of loss of protection as a patient approaches the average time that protection is known to decrease. I do think that it is important to continue to have yearly physical examinations because pets do not communicate illness well, in many instances, and because things like ear infections, dental problems, cataracts, etc. are hard for many owners to detect but are detectable by someone who knows what to look for. I am not sure if there is a published reference for the duration of immunity studies in dogs at this time, although the data has been reported at several conferences. Dr. Schultz at the University of Wisconsin (I think) has been one of the main sources of information so watching for studies using his name for search engines might allow you to locate the information as soon as it is published and makes it to the Internet. There was a review of vaccination practices in one of the Kirk's Current Therapy books, which I think was in Kirk's XII but might have been in Kirk's XI. Mike Richards, DVM 10/31/2000

Vaccinations and titers

Question: What is your opinion of using titres to determine whether a dog should receive booster vaccinations? I have read in several articles that the current thinking is dogs are being vaccinated more often than is needed. After discussing this with our local vet and doctors at NC Veterinary College we decided to put our Jack Russells on a three-year schedule. However, one of our dogs, Russell, has had some serious health problems. We almost lost him a couple of years ago to some kind of immune mediated disease (the doctors at NCSU-VTH were never sure exactly what the problem was). He now takes colchicine and ursodiol for portal hypertension and is on a restricted diet (potato and duck) for colitis. Since no one knows what caused his original problem, it makes us very nervous to give him any kind of drug he doesn't have to have. His doctors suggested he take plain old-fashioned Heartguard, and I won't even use any of the new flea products on him, I use a flea comb instead, It has now been three years since Russell has had any vaccinations except for rabies. One of the residents at the Veterinary Teaching Hospital suggested we have titres run to show his antibody level. We did this through our regular vet and the results showed that he's in good shape. Later when we mentioned this to another resident at the NC Vet Hospital she said no one really knows what these titres mean. So, Dr. Richards, what do you think (besides that we're way too overprotective of our dogs)? Thanks for any advice you have. I really enjoy reading the Digest every month, and I appreciate all the effort that goes into it and your website. Miriam

Answer: Miriam- It is likely that dogs which are vaccinated yearly are vaccinated more often than is necessary for several diseases (the viral illnesses) and that they are not vaccinated as often as necessary to provide protection from others that are necessary in some situations (bacterial illnesses such as leptospirosis and bordetellosis). However, there is a great deal of controversy and confusion regarding this topic. One problem is that there are several vaccine strains used to provide protection for the various diseases vaccines protect against. Studies have generally looked at one or two vaccine strains and it is hard to be sure that all of them provide the same length of protection. However, I think it is likely that distemper vaccine provides protection for at least three years and that parvovirus vaccine probably provides lifelong protection after the one year booster is given. If vaccination for leptospirosis or bordetellosis is necessary for your dogs, these vaccines usually provide protection for less than a year. The major problem with using titers to evaluate when to give vaccines, other than expense, is that there isn't much agreement on what represents a protective titer at the present time. It is known that some dogs with high titers will develop distemper when exposed to the virus. It is also known that some dogs who have been vaccinated but who have no measurable titer will resist infection when exposed to the virus. The only really reliable way to tell how long a vaccine will provide protection is to do challenge studies -- to vaccinate a group of dogs and then expose them to the virus after specified intervals, to determine how long the vaccine will provide protection. Ideally, this would be done by each vaccine manufacturer or an independent party willing to test every vaccine strain. Once it is known how long a vaccine provides protection, it would be easier to figure out reasonable vaccination intervals. At the present time, the best approach to deciding how frequently to vaccinate is to evaluate the potential risks to the patient of the virus and then the potential risks of the vaccine and then to balance those against the need for protection. I think that it is usually safe to go to longer vaccine intervals and that three years is reasonable at this time. Mike Richards, DVM 9/15/2000

Distemper vaccine

Question: This is in regard to a reply by Mike Richards, DVM about concerns of distemper. In his reply he states "Some people think that the solution to the "window of opportunity" for the virus -- the time when it will cause disease even if a puppy has been vaccinated --- is simply to vaccinate more frequently. The flaw in this logic is that there are studies that demonstrate that vaccines for the same virus administered closer to two weeks apart may interfere with each other -- and lead to DECREASED immune response. Plus, no matter how frequently vaccines are given there is a short time period when the puppy is not protected. We choose a three week interval for vaccinations at our practice, starting at six weeks, just because it seems like a reasonably practical interval. " I would like to know the references he used for this statement as a DVM I know vaccinates puppies every 2 weeks until 16 weeks and I am concerned we may be vaccinating too much. I would like to pass his refernces to the Dr. Thank You Mark

Answer: Mark- The concept of antigenic interference is mentioned in several textbooks but I have had a hard time tracking down the initial research on it. However, there is a study done in greyhounds (search on "McMillen GL" on the PubMed web site to find it) that examines this concept. In this study, there was no particular benefit, nor any particular disadvantage, to vaccinating very frequently, although there was slightly (key word -- not significant, just slightly) better immune responses in the dogs vaccinated less frequently. Of course, there is a lot to be said for vaccinating less frequently if it works just as well. I am glad that you sent your question, as it made me search again for information on this topic. Mike Richards, DVM 3/2/2000

Recombitek (TM)

Q: Dear Dr. Mike: I hope this is a correct address to send inquiries - I found your useful Web site (vetinfo), and wanted to ask a question My question concerns adverse reactions to Recombitek. On 7 March, my 10-year old Lab had his regular shots for DIS/HEP/LEP/PAR/PARV, this time (the first time, I believe) using Merial's Recombitek. A few days later, we noticed a decline in his appetite (VERY unusual for this guy), and shortly after, he stopped eating altogether and became very lethargic. When we noticed he also seemed to have a fever, we took him to the vet. He had a fever of 104.5, which rose to 107 after a day of observations and tests. He was treated initially with antibiotics, but when he failed to respond and no problems turned up in the standard blood, urine, and feces tests, the vet concluded that it might be an autoimmune reaction, and began treating him with Prednizone (40 mg/day) while continuing the antibiotic. He responded immediately, and now (+ 2 days) seems completely better. Our vet did not know what may have triggered the autoimmune reaction, but admitted that the timing after using the Recombitek vaccine was suspicious. The dog has never had a reaction to other vaccines, but does have some allergies (severe reaction twice to bee stings; flea allergic reactions; some food allergies manifested in inflamed ear flaps). Could allergies to Recombitek play a role? I checked the FDA site and found no reported adverse reactions to Recombitek - but perhaps this is because it is new (and I'm told reporting is only required, or summarized, once a year?). Do you have any further information, or advice about where to seek it, on adverse reactions to Recombitek or any of its (active, inactive) ingredients? Thanks for your help. Jeff

A: Dear Jeff Recombitek (TM) is a much different vaccine than the usual ones used in veterinary medicine. It is the first of what will probably be several recombinant gene vaccines. Canarypox virus, which should not cause disease in dogs, is altered so that it produces the portions of the canine distemper virus that allow immunity to develop. In theory, this vaccine should cause very few reactions. If distemper were the only virus administered that might be true. Recombitek is a combination vaccination, though. It comes in several formulations, each of which has several other viral ingredients. The other components are not produced with recombinant gene technology and are just as likely to cause reactions as they would in any other vaccine combination. Overall, these reactions are still pretty unusual but do occur occasionally. I have been using Recombitek and we have seen some lethargy and soreness in a few dogs. At present we do not think these reactions are more common than with other vaccines we have used, but we have spoken with our Meriel sales representative about them, since we were hoping there would be less reactions with Recombitek. We have not had a reaction of the magnitude you describe. That is the what I know at this point. You should insist that your vet call Meriel and report this possible reaction. Unless veterinarians do this, there will be no suspicion on the part of the company or regulatory agencies that a reaction occurred. If Recombitek is not the cause, a pattern of reactions will not occur. If it is the cause, reported reactions will usually allow that to be proven. Sometimes, just one batch of vaccine has a problem and sometimes the problem is bigger than just one batch. The only way anyone will know is through reaction reports. Ask your vet what the company said in response to the report and if you are not satisfied, call them yourself. Meriel is a new company, formed by the merger of Merck's animal health division and Rhone-Merieux's animal health division. Rhone-Merieux has been very reputable in the past when dealing with vaccine problems. I think that will still be the case with the new company. Mike Richards, DVM

Annual Vaccinations

Q: I have two dogs with various physical problems that are going to be due for their annual immunizations shortly. With all of the discussion lately about whether to immunize annually or not, I am at a loss - my bouvier has had Rocky Mountain Spotted Fever and also glaucoma with resulting eye implant surgery. Her other eye is still OK. She is 8 years old. My border collie is 3 years old and has had ehrliciosis and seizures. It is still unknown if the seizures were caused by the ehrliciosis. What is your feeling about giving annual immunizations other than rabies - I know I must get a rabies vaccine annually in Florida. However I am unsure whether to do titers for the rest of the vaccines. What is your feeling on this? Thanks. Sue

Answer: Sue- Please don't take this as an effort to evade your question -- but I am just about as confused about the annual vaccination issue as everyone else, at this point. In cats, there is one published study, that was well done, that supports triennial vaccination in cats since titers were at levels judged to be protective for longer than that for the routine cat vaccinations (feline leukemia vaccination and feline infectious peritonitis vaccination were not included in this study). This, combined with the low incidence but terrible consequences of cancer formation (sarcoma) at vaccination sites in cats has been enough to sway us to go to a three year vaccination protocol in cats. There are veterinarians that question this protocol for legitimate reasons, such as only one brand of vaccine being tested and the use of titers instead of disease challenge studies. But I am still in the group of vets that favors longer vaccination intervals for cats. In dogs the available studies are pretty conflicting as to how long vaccinations really last. There are published reviews that state that one year intervals should be maintained and there have been titer studies of individual components of the canine vaccination series that support longer vaccinations intervals, although I am not sure if these have been published at this time. To date, we have not identified a problem in dogs similar to the one in cats that makes vaccination interval a really important issue, although most vets do recognize that vaccinations cause occasional serious complications such as anaphylactic reactions and rarely immune mediated hemolytic anemia. Given this situation, we are currently still giving annual boosters to our canine patients if we do not have compelling reasons not to do that. The other factor that has to be evaluated is the risk of developing one of the diseases that the vaccines protect against. House dogs that don't have much contact with other dogs don't have a high risk of exposure. Dogs that attend shows or sporting events or that live in cities and are walked in parks that hundreds of other dogs are also walked in have a high risk of exposure to infectious diseases. Your dogs probably have a risk factor between these two extremes and you and your vet can discuss how much risk there appears to be in their lifestyle. Two common canine vaccinations, leptospirosis and bordetella probably do not last a year. Leptospirosis vaccination probably is effective for six to eight months and bordetella for six to eleven months -- MAYBE a year in some cases. If these are significant risk it may be necessary to vaccinate more frequently than annually. Modified live virus vaccinations are slightly immunosuppressive for a couple of weeks in most dogs. This may be problematic in the case of an illness like ehrlichiosis where there is some question over the ability to ever reliably cure a patient and therefore some risk of recurrence of the illness when immunosuppression occurs for any reason. There is some chance that the reported recurrences may be new infections so that is why confusion still exists over this issue. I do not recall seeing a recommendation from an infectious disease specialist to stop vaccinating dogs after infection with ehrlichiosis, though. We usually go ahead and vaccinate dogs that have seizures and Rocky Mountain Spotted Fever is not supposed to have the tendency to become chronic in the way the ehrlichiosis appears to. So the answer to your question, really, is this: if the risk to your dogs of infectious diseases included in the vaccinations seems low, at least your bouvier may be better off without vaccination on an annual basis but no one that I know seems to have a handle on how long the interval between vaccinations should be for minimum protection. In our practice it is unusual for us to see distemper, parvovirus or hepatitis in dogs that have been effectively vaccinated in their younger years even if the owners quit following the recommended vaccination schedule. Most vets admit that this is the case in their practices, as well. But many vets have seen distemper or parvovirus in dogs that have had at least some vaccinations. So, if there are significant risk factors in their lifestyle, then for now it may be best to go ahead and vaccinate annually or in the case of the bacterial illnesses even more often than annually. The best bet is to discuss these concerns with your vet and then to make a decision on an appropriate vaccination interval. Personally, I think it is really not logical to give rabies vaccinations annually. There is good evidence that this is not necessary --but it is legislated in several states. I am hoping that the veterinary profession will not follow the path of the state legislatures and fail to recognize when there really is good evidence that vaccinations provide protection for longer intervals. Hope this helps, even though it isn't a definitive answer. Mike Richards, DVM 6/23/99

First Vaccinations

Q: Dear Dr. Richards: Please tell me why adult animals need 2 inoculations approx. 3 wks apart the 1st time they are vaccinated. I understand the need in puppies and kittens, colostrum, mothers antibodies, etc., but why adults. What happens if they only get 1 vaccination at first then 1 every year, does it do them any good? Also my neighbor just gave her dog an expired (1 month out) vaccine. Will this harm the dog? Should she get another vaccination? Thanks for answering my vacuous questions. Carol A: Carol- Modified live vaccines probably confer adequate immunity without being repeated as long as there are no maternal antibodies or other immune system diseases interfering with the action of the vaccine. Killed vaccines need to be repeated in order to be effective in many cases because they do not continue to stimulate an immune response by viral reproduction like modified live vaccines. In other cases killed vaccines are mixed with powerful adjuvents (substances that stimulate immunity) in order to ensure a good response from the immune system. Rabies vaccines are an example of a killed vaccine with adjuvents. I am comfortable giving 1 modified live vaccination for the diseases that I vaccinate for when a previously unvaccinated dog who is at least 16 weeks of age or older comes to the clinic. I think it is OK to go to annual boosters after this vaccination but some vets do not think so and will insist on a second vaccination. They may have experiences to suggest that this degree of caution is a good idea that I simply haven't had. If the vaccine that your friend used was properly cared for it is likely that it still worked despite being slightly out of date. I have to admit that if I noticed I had done that to one of my pets I'd probably go ahead and repeat the vaccination, though. There is not likely to be any harm other than not getting adequate protection from the vaccine. Mike Richards, DVM Puppy Vaccination schedule Q: Dear Dr. Mike, A co worker recently purchased a five week old german shepherd puppy. This CKC registered breeder suggested to her that the puppy should not be vaccinated until after she is four months old, due to the fact that she has her mothers antibodies in her system to protect her. After speaking with a few different veterinary professionals, she has realized that this is likely a dangerous path to take. However, she is unsure as to when she should begin vaccination. The puppy will be six weeks old in a couple of days. She has had diarrhea today, and has a voracoius appetite. Could the diareha be from the stress of separation from her mother, and change in environment, or is there something to be more concerned about? When should she see her veterinarian to begin vaccination? Thank you for your assistance. We would appreciate any input you may have to offer.

A: Tracy- Most veterinarians suggest beginning the vaccination series at 6 weeks of age. With the new vaccines available now, it should take three vaccinations spaced about 3 weeks apart to ensure vaccine success in most puppies. A convenient schedule is then 6, 9 and 12 weeks of age. While it may not be as necessary with the new vaccines, a cautious approach would be to vaccinate one more time at 16 weeks of age, too. It is not unusual for puppies to get diarrhea when separated from their mother but if it continues, it is definitely a good idea to have the pup checked. There are some serious diseases that have diarrhea as a first or early sign and getting these treated early can make a big difference. Hope all is well now and that your friend has made vaccination arrangements. Mike Richards, DVM

Do I Really Need to Vaccinate My Pet?

The short answer is YES - for many vaccinations and MAYBE NOT for others. For more details, keep on reading!


In all states, rabies vaccinations are required by law. The first rabies vaccination is good for one year. In many states subsequent vaccinations are good for three years. In other states, they are only valid for one year by law. Please check with your vet to determine the legal requirements in your state. Vaccinating your pet for rabies may literally save its life for two reasons. Rabies is a threat in many areas and it is a horrible disease. In addition, an unvaccinated pet who bites a human being, even by accident, is subject to long quarantine periods or even death for the purpose of testing for rabies infection. Don't risk your pet's life. Get its rabies vaccination.

Other vaccinations vary in their benefits and risks.

It is extremely important to vaccinate puppies and kittens successfully for several diseases. This is the time that they are most likely to contract many of the diseases which we vaccinate for. Early protection can prevent the heartbreak of dealing with parvovirus in a puppy or feline leukemia in a kitten. Please contact your vet and work with him or her to establish and follow a good vaccination schedule for your pediatric pet! A series of vaccinations is given in the hopes of protecting all puppies and kittens as early as possible but continuing to vaccinate until all patients are protected.

That said, what do we vaccinate for and who needs the vaccinations?

For dogs, the following vaccinations may be advised, depending on the circumstances in your area. They are often combined into a single injection containing several components. Since several combinations are marketed, it is possible to tailor the vaccination schedule for puppies and adult dogs to match their needs.


Distemper vaccination is important for all puppies. This disease is still present in most areas and it is still hard to treat successfully. Even when a puppy is nursed through the acute phase of the disease there can be long term health problems. The most common of these is a tendency to develop seizures.

Adenovirus Type 2

This virus causes a form of kennel cough and also protects against hepatitis in dogs. This is fortunate because there were more vaccine reactions using the hepatitis virus itself , even in a weakened state. While viral hepatitis is not as common as it once was in dogs, it has not been eliminated as a threat.


This is actually a bacterial disease, so the protective "vaccination" is actually a "bacterin". In many areas of the country, this disease is not common and the leptospirosis portion of the vaccine combinations is thought to be the most common cause of reactions. For this reason, many veterinarians no longer include it in their vaccination recommendations, IF they practice in an area in which it is not common. Your vet can tell you whether or not it is necessary in your area.


Parainfluenza must be an inexpensive virus to include in vaccines. It is in almost all the combination vaccines even though it is probably only a minor contributor to the problem of tracheobronchitis (kennel cough) in dogs. Vaccine reactions to this virus seem rare.


Parvovirus is probably the most common viral illness of dogs at the present time. It is much more common in puppies than it is in adult dogs. It can be very hard to successfully vaccinate a puppy for this disease because the antibody protection the puppy acquires from its mother can interfere with vaccination. It is important to vaccinate puppies every three to four weeks for this virus starting at 6 weeks of age and continuing until they are at least 16 weeks of age and preferably 20 weeks of age. It is possible that this vaccine confers lifelong immunity once it does work but most veterinarians continue to recommend yearly vaccination for it. It seems prudent to at least get the vaccination at one year of age. Since it is combined with the other vaccines it is often easier just to give it yearly with them.


Coronavirus may cause viral diarrhea and may make fatality from parvovirus more likely if the infections occur concurrently. On the other hand, this virus causes minimal damage to the intestines and may not cause clinical illness on its own. It just depends on whose studies you believe. Personally, I do not recommend the use of coronavirus vaccine.


Bordetella is the most common cause of tracheobronchitis (kennel cough) in dogs. It is a bacterial illness that is most common among dogs that congregate at things like shows, kennels or other places frequented by large numbers of dogs at once. It does not appear that this bacterin gives a full year of immunity in many instances. For dogs that are often exposed to situations in which the infection is likely probably should be vaccinated twice a year. There are intranasal as well as subcutaneous bacterins available for this disease. The intra-nasal bacterin confers immunity more quickly but the injectable version may last longer.

Lyme disease (Borrelia)

Lyme disease is caused by a bacterial organism, Borrelia burgdorferi . It is carried by Ixodes species of ticks and may have other tick or insect carriers. It is more common in some areas of the United States than in others. Your vet can tell you whether it is necessary to protect against this disease in your area. There is a new Lyme bacterin on the market that Rhone-Merieux has produced using recombinant gene techniques. This bacterin only uses a portion of the bacteria which the body defenses recognize and form antibodies against. Because the whole Lyme bacteria is not present, it appears that there will not be the problem of the vaccine causing symptoms of Lyme disease. In addition, this bacterin does have a validated one year duration of immunity. It is a new product and like all new products there is a period when everyone looks hard for previously unknown reactions but if "vaccination" against Lyme disease seems necessary in your area, I'd definitely use this one.

Lyme Disease Vaccination

Q: Dear Dr. Mike, Are Lyme Vacs useful? I've heard they're not. thanks

A: The whole killed Lyme bacterins are of questionable usefulness. There is some evidence that the immune reaction to the bacterins may produce symptoms of the disease, even pretty severe ones. There is a new Lyme bacterin on the market that Rhone-Merieux has produced using recombinant gene techniques. This bacterin only uses a portion of the bacteria which the body defenses recognize and form antibodies against. Because the whole Lyme bacteria is not present, it appears that there will not be the problem of the vaccine causing symptoms of Lyme disease. In addition, this bacterin does have a validated one year duration of immunity. It is a new product and like all new products there is a period when everyone looks hard for previously unknown reactions but if "vaccination" against Lyme disease seems necessary in your area, I'd definitely use this one. Mike Richards, DVM

ps -- just a technicality - because Lyme disease is caused by a bacteria, the "vaccine" is actually a "bacterin". But saying "I want to get my pet a bacterination" just doesn't sound right, does it?


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...