From ACVIM Forum 2010–Poster: Antibodies to Feline Vaccines

I’m currently attending the American College of Veterinary Internal Medicine (ACVIM) continuing education forum, followed by the Evidence-Based Veterinary Medicine Association (EBVMA) symposium, and between lectures, labs, and other events I’m going to try and post tidbits of interest I come across.

This morning I looked at the poster presentations. Posters at scientific meetings are like mini journal articles. They usually report on small studies, often with significant methodological limitations, and they are considered a lower level of evidence than peer-reviewed papers in the journals. This is not a criticism of them as they are a very important starting point for deciding whether to pursue new ideas. It is just important to recognize their limitations and to take a cautious approach to both positive and negative findings presented as posters.

Some researchers are looking at a possibility that leftover bits of feline kidney proteins in vaccines manufactured using cat kidney cells might be a risk factor for immune-mediated diseases which are relatively common in the cat, especially some types of kidney disease and inflammatory liver and intestinal diseases. A couple of papers (1, 2, 3) have shown that cats do form antibodies to some of these proteins after receiving vaccines, but no conclusive evidence has linked this to clinical disease. The concern is a significant one. If it is true, then changes need to be made in vaccine manufacture and use, and there is the potential to reduce significantly an important set of cat diseases. However, if it is not true, then suggestive but inconclusive research on the possibility will only serve to fuel anti-vaccine fears unnecessarily.

The same research group behind the previous papers presented a poster at the ACVIM forum looking for associations between bloodwork values and the presence of antibodies to several feline kidney proteins of concern.

Association Between Feline Antibody Responses to Crandell Rees Feline Kidney (CRFK) Cell Lysates, Alpha-Enolase, and Annexin A2 and Biochemical Abnormalities in 1,477 Privately-owned Cats. J.C. Whittemore; J.R. Hawley; S.V. Radecki; M.R. Lappin



In this project, blood submitted to a commercial laboratory from 1,477 cats was analyzed. No information about age, sex, vaccination or medical history, or health status was available for specific patients. 16 biochemical measures were compared with the presence of antibodies against 3 feline kidney proteins known to be present in some vaccinated cats. The results were fairly inconsistent and not supportive of the hypothesis that antibodies against feline kidney antigens in vaccines is a cause of disease. For one antigen (CRFK) there was a positive association with one of the 16 measured values, bilirubin (a measure of possible liver disease, among other things). There was also a significant negative association with 2 of the 16 values, creatinine (a measure of kidney function) and alkaline phsophatase (a measure of possible liver disease). The other two antibodies examined both had negative associations with blood sugar, a common blood protein and, for one of them, alkaline phosphatase.

In general, then, these results don’t suggest a strong association between chemistry abnormalities in the blood and the production of antibodies against feline kidney proteins found in vaccines. There was no association with most of the values measured, and most of the associations that were found were negative, which if they were clinically significant might suggest the antibodies somehow protected against liver and kidney diseases, which is highly unlikely.  Given all the limitations of the study, especially the lack of any information about the cats the blood came from, this by no means rules out the possibility that the underlying theory is correct, it simply provides a tiny bit of low-level evidence against it. Undoubtedly, this group and others will continue investigating the problem and will hopefully eventually amass sufficient information for a strong conclusion one way or the other. In the meantime, though, it is appropriate to reassure cat owners that the hypothesis is a real but so far unproven concern, and it is not yet appropriate to alter vaccination practices on the basis of it.

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6 Responses to From ACVIM Forum 2010–Poster: Antibodies to Feline Vaccines

  1. Dr. Jordan says:

    Gee why do you think then that only vaccinated individuals were found to have autoantibodies in the PErdue study? Gee why do you think only the vaccinated cats develop these types of kidney failures? Gee why do you think the cats vaccinated developed the aluminum adjuvant soft tissue sarcomas and the vaccinated dogs and the vaccinated ferrets?
    Gee, when our veterinary vaccine researcher says cats only need one distemper vaccine for their entire life……perhaps he knows what happens with injections of vaccines?????????

  2. skeptvet says:

    Dr. Jordan,

    The hysterical tone of your comment, not to mention the entire content of your web site (, illustrates the irrational and unscientific nature of your thinking. Or to quote your own words:

    “…true health and wellness comes from a very natural setting and one from the relationship of the individual in balance with the earth and all of the treasures a healthy ecosystem has to offer; optimal nutrition from an ethical position of taking only what you need and knowledge that the botanical treasures allow indeed for food to be your medicine and medicine your food. The important ingredient everyone also needs is right relationship with the other living organisms of the environment we share, respect for each other and the most holy relationship that of the one with the intelligence that designed this most wonderful system….Vaccines and drugs are at odds with the intelligence of the almighty….”

    Your faith in you own beliefs and the volume at which you shout them does not make them true.

    “Gee why do you think only the vaccinated cats develop these types of kidney failures?”
    There is no evidence this is true.

    “Gee why do you think the cats vaccinated developed the aluminum adjuvant soft tissue sarcomas and the vaccinated dogs and the vaccinated ferrets?”
    Vaccine-associated sarcomas in cats are a real phenomenon, and the Aluminum adjuvant is a likely, though not absolutely proven, cause. This is not, however, relevant to the issue in this poster. And there is no evidence that such a problem effects dogs or ferrets, so again you’re just making stuff up to suit your beliefs.

    “Gee, when our veterinary vaccine researcher says cats only need one distemper vaccine for their entire life……perhaps he knows what happens with injections of vaccines”
    Or perhaps he is simply wrong. How often a vaccine needs to be repeated is a complex and poorly understood calculation based on individual response, prevalence of the disease being prevented, efficacy of the vacine, and many other factors. A global statement like this applied to all cats is unjustified and guaranteed to be wrong. Not that it would mattter to you since you must likely view even one vaccine as one too many.

  3. Vaccine-associated sarcomas in cats are a real phenomenon, and the Aluminum adjuvant is a likely, though not absolutely proven, cause. This is not, however, relevant to the issue in this poster. And there is no evidence that such a problem effects dogs or ferrets, so again you’re just making stuff up to suit your beliefs.>>>>>>

    Any new looks that you know othat you know of with this dog vaccine sarcoma issue? below is all i have to give people
    art malernee dvm
    fla lic 1820

    Vaccination Sarcomas in Dogs


    Do Vaccine-Associated Sarcomas occur in Dogs? Most of us in oncology, and others,
    believe they do but little proof exists. In this Tumor Tidbit, I’ve included below the
    abstracts of two reports, one in dogs (2003) and one in cats (1996), that describe the
    differences that exist between sarcomas in vaccination and non-vaccination sites. To
    date, these are the only two “smoking gun” reports in the veterinary literature.

    Currently I serve on the AVMA Council of Biologic and Therapeutic Agents (COBTA) as the
    Small Animal Practice Representative. Many in our profession have voiced concerns
    regarding proper vaccination schedules in cats and in dogs, whether the terms “injection”
    or “vaccine-associated” should be used, and are there factors that may predict the onset
    or prognosis for an affected pet animal. I am very proud of the work performed to date,
    albeit slow, by COBTA and others in these important issues. Continued discussion in our
    profession, the Center of Veterinary Medicine, and the pharmaceutical industry needs to
    continue and focus on issues of fact, not fiction. This Tumor Tidbit is not intended to
    solve these issues but to add further fact to the discussion.

    Canine Study Abstract

    Fibrosarcomas at Presumed Sites of Injection in Dogs: Characteristics and Comparison with
    Non-vaccination Site Fibrosarcomas and Feline Post-vaccinal
    Fibrosarcomas. Vascellari M, Melchiotti E, Bozza MA, Mutinelli F. J Vet Med A Physiol
    Pathol Clin Med. 2003 Aug;50(6):286-91.

    Fifteen fibrosarcomas, surgically excised from presumed sites of injection in dogs, and
    10 canine fibrosarcomas excised from sites not used for injection were histologically
    and immunohistochemically compared with 20 feline post-vaccinal fibrosarcomas. Canine
    fibrosarcomas from presumed injection sites were of grade I (3), of grade II (4) and
    grade III (8). Two fibrosarcomas from non-injection sites were of grade I, four of grade
    II and four of grade III. Feline samples were classified as grade I (2), grade II (4)
    and grade III (14). All fibrosarcomas from presumed injection sites of both species
    showed lymphocytic inflammatory infiltration located at the tumour periphery, while two
    canine fibrosarcomas from non-injection sites showed perivascular inflammatory
    infiltration within the neoplasm. All samples were immunohistochemically examined for
    vimentin, smooth muscle actin, muscle specific actin and desmin expression. All tumours
    were positive for vimentin. Ten canine fibrosarcomas from presumed injection sites and
    all feline samples contained cells consistent with a myofibroblastic immunophenotype.
    Aluminium deposits were detected in eight canine fibrosarcomas from presumed injection
    sites and 11 feline post-vaccinal fibrosarcomas by the aurintricarboxylic acid method.
    The present study identifies distinct similarities between canine fibrosarcomas from
    presumed injection sites and feline post-vaccinal fibrosarcomas, suggesting the
    possibility of the development of post-injection sarcomas not only in cats, but also in

  4. skeptvet says:


    Those case reports are the only published reports I am aware of, and among oncologists there is some skepticism that they truly represent vaccine-associated sarcomas. The presence of adjuvant marks previous vaccination, but it doesn’t mean that was the trigger for tumor formation. If you biopsy the SQ of many dogs in that area, you’ll find adjuvant without tumor since it takes a long time to be cleared.

    In cats, the key factor that allowed association of VAS with vaccines was the epidemiological evidence. Rates of sarcomas increased markedly with the introduction of the relevant vaccine and adjuvants, etc. So in dogs, given the huge number vaccinated annually and the almost complete absence of reported sarcomas that follow vaccination in time and location in the expected way, it seems very unlikely that there is a true association. Of course, one can never prove a negative, but if this were a real problem, rather than an extremely rare idisyncratic response or coincidence, it’s hard to explain the lack of cases.

  5. I want to thank you for doing this. Last year, about a month after my cat (8 years) had his rabies shot, he presented Chronic Renal Failure, but he didn’t respond to treatment. (I had two cats with it in the past and knew the drill, so what my vet had to say held no surprises.) CRF has causes. Everything has causes, but I’ve only had one cat where the cause of his kidney failure was really pursued.

    Maximus’s death bothered me. I have a lot of friends doing “natural” (I’ve read and agree with you in that respect) and “organic” and (regrettably) anti-vax. I do not agree with anti-vax. Anti-vax for pets was a new experience for me. Among other things, I’ve seen repeated cases of parvo. I used to work at the University of Florida College of Veterinary Medicine and gained a great respect for the work of Veterinary researchers.

    But…when it was suggested, I couldn’t help thinking that it was the first three year vaccine he’d ever gotten.

    I tried to look things up, but heaven help me, it was all junk science clap trap and there was no way for me to wade through and find something real. I finally had to contact a friend at the vet school who contacted another doctor I’d known. They got back to me and told me there was absolutely nothing wrong with the vaccine.

    Not everyone can contact a friend and have her go to a friend who is a knowledgeable veterinary researcher. I am glad your site exists. There’s so much trash out there, it’s good to have a voice of reason.

  6. skeptvet says:

    Thanks. I’m glad the site was useful for you.

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