May 22, 2019
Vaccines are one of the most effective means for preventing disease ever developed and one of the great triumphs of scientific medicine. Widespread vaccination of children has dramatically reduced—and in some cases eliminated—infectious diseases that have plagued humanity for thousands of years.
There is less research evidence for the impact of vaccination in companion animals, but there is ample reason to believe vaccines have been equally successful in dogs and cats.3–7 Any veterinarian old enough to remember the emergence of canine parvovirus (CPV) in the U.S. in the late 1970s, for example, would probably testify to the efficacy of vaccination in reducing the incidence of this disease.5–7 There also is compelling evidence showing the reduction of both canine and human rabies cases due to vaccination programs aimed at dogs.8–12 And similar to smallpox, the veterinary disease rinderpest was eradicated largely due to the use of an effective vaccine.13
Despite the evident success of vaccination in reducing morbidity and mortality, there has always been controversy about the practice.14 The introduction of widespread vaccination in children was initially met with resistance and legal challenges. There was fear about the safety of vaccines, as well as resistance rooted in political and religious beliefs. This resistance was diminished by the dramatic reduction in childhood disease accomplished by vaccination programs in the early 20th century. With the elimination of smallpox, the near elimination of polio, and dramatic reductions in many common and familiar childhood diseases, the vast majority of parents embraced routine vaccination.
Today, however, most parents belong to generations that have grown up in a world largely free of vaccine-preventable infections. They are unfamiliar with diseases their grandparents knew all too well, so their concern about them is low, while fear of vaccines and resistance to vaccination is growing again.14–16 The latest surge in the modern anti-vaccine movement can be linked to a scientific paper suggesting the measles, mumps, and rubella vaccine (MMR) increased the risk of autism in children.17 This paper has since been withdrawn due to fraud, the author has been stripped of his medical license, and numerous studies have definitively disproven any link between autism and vaccination.18–23 Nevertheless, the avalanche of fear set off by such a claim continues, and outbreaks of vaccine-preventable diseases are occurring in children around the world associated with declining vaccination rates.16,24,25
The anti-vaccine movement has not been limited to human medicine. There are all too many activists discouraging vaccination of dogs and cats, and blaming vaccines for a panoply of diseases.26–29 Fads and irrational ideas about health pertaining to humans often get adopted and translated to pet health care. Phobia about gluten and grains in human diets undoubtedly contributed to the grain-free pet food craze.30 And fears of the ill-defined menace of “chemicals,” genetically modified organism (GMO) foods, and other supposed health hazards for people also infect pet owners and veterinary professionals.30–32
As an extreme example, some anti-vaccine activists have made the claim that vaccines cause autism in dogs.33,34 While the concept of an animal model for autism as a neurologic disease is not inherently unreasonable, there is no definitive evidence a condition analogous to autism exists in dogs.35,36 Of course, even if it does, there is absolutely no reason to associate any such condition with vaccination. This is clearly an anti-vaccine argument originally developed for children and then adopted as an argument against vaccination of pets as well.
Like any medical intervention, vaccines in pets are not entirely free of risks.6,37–43 Adverse effects ranging from acute hypersensitivity reactions to vaccination and to serious and delayed diseases, such as feline injection-site sarcoma, do occur. Most of these are either mild and treatable or very uncommon, but vaccines clearly have some dangers.
For most of the diseases blamed on vaccines, however, the evidence ranges from weak (e.g. immune-mediated thrombocytopenia and hemolytic anemia)37–41 to nonexistent (e.g. vaccinosis, a catch-all concept invented by a homeopath in the 19th century and still used to blame chronic diseases of all sorts on vaccination).44–46 The risks of vaccinations must be assessed in comparison to their benefits, and it is obvious core canine and feline vaccines, used appropriately, offer more than enough benefits to justify their risks.
Sadly, anti-vaccine propaganda comes not only from laypeople, but also from some within the veterinary profession.46–52 Reasonable, evidence-based inquiry into the risks of vaccination and the proper use of vaccines is appropriate and necessary. However, vaccine opponents often engage in fear-mongering and exaggeration of the risks (see the sidebar in the XXXX of this page), or in the promotion of unproven or ineffective alternative immunization practices.
Many of the most vociferous opponents of vaccination also are proponents of alternative medicine. Research has consistently found an association between vaccine refusal and the use of alternative therapies in humans.53–60 Parents who use these methods are less likely to follow recommended vaccination schedules. These parents often explain their resistance to vaccines as part of a comprehensive ideological preference for supposedly “natural” health care and a suspicion of technology and modern scientific medicine. Alternative medicine providers, such as naturopaths, chiropractors, and homeopaths, also frequently discourage vaccination.53,55–59,61–66
Though there is a lack of formal research on this subject in veterinary medicine, a similar relationship is often apparent in the pronouncements of vaccine opponents. The strongest resistance to routine vaccination comes from advocates for alternatives to conventional science-based medicine, and these activists also frequently oppose other elements of conventional treatment. Certainly, there are integrative practitioners who support vaccination, but the resistance to vaccines also comes predominantly from pet owners and veterinarians sympathetic to alternative medicine.
In human health, the harmful effects of the anti-vaccine movement are clear. Outbreaks of measles, whooping cough, and other preventable childhood diseases are occurring with increasing frequency, and these are driven predominantly by unvaccinated individuals.24,25,67 Avoidable suffering and death have been caused by the use of excessive and irrational fear of vaccines to discourage parents from properly immunizing their children.
There is little data to determine the impact of the anti-vaccine movement on vaccination rates or infectious disease incidence in dogs and cats. Vaccine uptake is well below levels needed for effective herd immunity in some populations, but the cause for this is unclear.68–71 Media reports also suggest vaccine resistance is a growing phenomenon among certain groups of pet owners, but there is no clear research data evaluating this claim.26,28,29 A few surveys of pet owners regarding vaccines have provided variable results, with some finding concerns about vaccine safety discourages vaccination and others not identifying this as a significant factor.69–74 It seems likely the causes and effects of vaccine resistance in veterinary medicine resemble those in human health care, but there is no strong evidence to demonstrate this.
Veterinary medicine often borrows from human medicine. The best version of this practice is when new knowledge and novel therapies discovered for people are studied and ultimately adapted to improve the health of veterinary patients. Unfortunately, pet owners and veterinary professionals also sometimes adopt and apply bad ideas from the human health field that can undermine effective, evidence-based veterinary care. The excessive fear of vaccines and the decline in vaccination of companion animals appear to be examples of irrational and unscientific health-care practices bleeding over from the human to the veterinary health-care domain.
It is incumbent on veterinarians to be aware of the fears and misconceptions pet owners, and even some of our colleagues, may have concerning vaccines and to promote more evidence-based views and practices. Vaccines have protected the lives and health of countless veterinary patients, and we should resist efforts to undermine the use of this powerful health-care tool.
Brennen McKenzie, MA, MSc, VMD, cVMA, discovered evidence-based veterinary medicine after attending the University of Pennsylvania School of Veterinary Medicine and working as a small animal general practice veterinarian. He has served as president of the Evidence-Based Veterinary Medicine Association and reaches out to the public through his SkeptVet blog, the Science-Based Medicine blog, and more. He is certified in medical acupuncture for veterinarians. Columnists’ opinions do not necessarily reflect those of Veterinary Practice News.
1 Vanderslott S, Roser M. Vaccination. OurWorldInData.
2 Roush SW, Murphy T V, Vaccine-Preventable Disease Table Working Group. Historical Comparisons of Morbidity and Mortality for Vaccine-Preventable Diseases in the United States. JAMA. 2007;298(18):2155. doi:10.1001/jama.298.18.2155
3 Patel JR, Heldens JGM. Review of companion animal viral diseases and immunoprophylaxis. Vaccine. 2009;27(4):491-504. doi:10.1016/j.vaccine.2008.11.027
4 McVey S, Shi J. Vaccines in Veterinary Medicine: A Brief Review of History and Technology. Vet Clin North Am Small Anim Pract. 2010;40(3):381-392. doi:10.1016/j.cvsm.2010.02.001
5 Houston DM, Ribble CS, Head LL. Risk factors associated with parvovirus enteritis in dogs: 283 cases (1982-1991). J Am Vet Med Assoc. 1996;208(4):542-546. http://www.ncbi.nlm.nih.gov/pubmed/8603904. Accessed March 17, 2019.
6 Appel MJ. Forty years of canine vaccination. Adv Vet Med. 1999;41:309-324. http://www.ncbi.nlm.nih.gov/pubmed/9890024. Accessed March 17, 2019.
7 Brady S, Norris JM, Kelman M, Ward MP. Canine parvovirus in Australia: The role of socio-economic factors in disease clusters. Vet J. 2012;193(2):522-528. doi:10.1016/j.tvjl.2012.01.025
8 Zinsstag J, Lechenne M, Laager M, et al. Vaccination of dogs in an African city interrupts rabies transmission and reduces human exposure. Sci Transl Med. 2017;9(421):eaaf6984. doi:10.1126/scitranslmed.aaf6984
9 Zimmer BL, Gamble L, Mayer D, Foster R, Langton J. Canine rabies vaccination reduces child rabies cases in Malawi. Lancet (London, England). 2018;392(10153):1115-1116. doi:10.1016/S0140-6736(18)32175-5
10 Fitzpatrick MC, Shah HA, Pandey A, et al. One Health approach to cost-effective rabies control in India. Proc Natl Acad Sci U S A. 2016;113(51):14574-14581. doi:10.1073/pnas.1604975113
11 Knobel DL, Arega S, Reininghaus B, et al. Rabies vaccine is associated with decreased all-cause mortality in dogs. Vaccine. 2017;35(31):3844-3849. doi:10.1016/j.vaccine.2017.05.095
12 Wera E, Mourits MCM, Hogeveen H. Cost-effectiveness of mass dog rabies vaccination strategies to reduce human health burden in Flores Island, Indonesia. Vaccine. 2017;35(48):6727-6736. doi:10.1016/j.vaccine.2017.10.009
13 Morens DM, Holmes EC, Davis AS, Taubenberger JK. Global rinderpest eradication: lessons learned and why humans should celebrate too. J Infect Dis. 2011;204(4):502-505. doi:10.1093/infdis/jir327
14 Wolfe RM, Sharp LK. Anti-vaccinationists past and present. BMJ. 2002;325(7361):430-432. doi:10.1136/BMJ.325.7361.430
15 Larson HJ, de Figueiredo A, Xiahong Z, et al. The State of Vaccine Confidence 2016: Global Insights Through a 67-Country Survey. EBioMedicine. 2016;12:295-301. doi:10.1016/j.ebiom.2016.08.042
16 Hussain A, Ali S, Ahmed M, Hussain S. The Anti-vaccination Movement: A Regression in Modern Medicine. Cureus. 2018;10(7):e2919. doi:10.7759/cureus.2919
17 Wakefield AJ, Murch SH, Anthony A, et al. Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. Lancet (London, England). 1998;351(9103):637-641. http://www.ncbi.nlm.nih.gov/pubmed/9500320. Accessed January 4, 2019.
18 Kmietowicz Z. Wakefield is struck off for the “serious and wide-ranging findings against him”. BMJ. 2010;340:c2803. doi:10.1136/bmj.c2803
19 Uno Y, Uchiyama T, Kurosawa M, Aleksic B, Ozaki N. Early exposure to the combined measles–mumps–rubella vaccine and thimerosal-containing vaccines and risk of autism spectrum disorder. Vaccine. 2015;33(21):2511-2516. doi:10.1016/j.vaccine.2014.12.036
20 Hviid A, Hansen JV, Frisch M, Melbye M. Measles, Mumps, Rubella Vaccination and Autism. Ann Intern Med. March 2019. doi:10.7326/M18-2101
21 Taylor LE, Swerdfeger AL, Eslick GD. Vaccines are not associated with autism: an evidence-based meta-analysis of case-control and cohort studies. Vaccine. 2014;32(29):3623-3629. doi:10.1016/j.vaccine.2014.04.085
22 Madsen KM, Hviid A, Vestergaard M, et al. A Population-Based Study of Measles, Mumps, and Rubella Vaccination and Autism. N Engl J Med. 2002;347(19):1477-1482. doi:10.1056/NEJMoa021134
23 Jain A, Marshall J, Buikema A, Bancroft T, Kelly JP, Newschaffer CJ. Autism Occurrence by MMR Vaccine Status Among US Children With Older Siblings With and Without Autism. JAMA. 2015;313(15):1534. doi:10.1001/jama.2015.3077
24 Feikin DR, Lezotte DC, Hamman RF, Salmon DA, Chen RT, Hoffman RE. Individual and community risks of measles and pertussis associated with personal exemptions to immunization. JAMA. 2000;284(24):3145-3150. http://www.ncbi.nlm.nih.gov/pubmed/11135778. Accessed March 20, 2019.
25 Phadke VK, Bednarczyk RA, Salmon DA, Omer SB. Association Between Vaccine Refusal and Vaccine-Preventable Diseases in the United States. JAMA. 2016;315(11):1149. doi:10.1001/jama.2016.1353
26 Lengyel K. Anti-Vaccination Movement Going to the Dogs? Am Vet. August 2017.
27 Clifton J. Stop the Shots! : Are Vaccinations Killing Our Pets? New York, NY: Foley Square Books; 2007.
28 Duan N. Inside the World of Pet Anti-Vaxxers. The Awl.com. January 2018.
29 Kluger J. Some Anti-Vaxxers Aren’t Getting Their Pets Vaccinated. Here’s Why That’s So Dangerous. Time.com. March 20189.
30 Dodds WJ, Laverdure D. Canine Nutrigenomics : The New Science of Feeding Your Dog for Optimum Health.; 2015. https://www.worldcat.org/title/canine-nutrigenomics-the-new-science-of-feeding-your-dog-for-optimum-health/oclc/890808034&referer=brief_results. Accessed October 27, 2018.
31 McKenzie B. Is banning “artifical” ingredients based on fear or science? Vet Pract News. March 2019:36-37.
32 Becker K. How GMOs Can Affect Your Pet: Causes Tumors, Major Organ Damage and Premature Death – Is Your Pet at Risk? Healthypets at Mercola.com. https://healthypets.mercola.com/sites/healthypets/archive/2017/09/09/gmos-in-pet-food.aspx. Published 2017. Accessed March 20, 2019.
33 Raines K. Autism Symptoms in Pets Rise as Pet Vaccination Rates Rise – The Vaccine Reaction. The Vaccine Reaction. https://thevaccinereaction.org/2017/04/autism-symptoms-in-pets-rise-as-pet-vaccination-rates-rise/. Published 2017. Accessed March 12, 2019.
34 Ducharme J. Veterinary Group: Dogs Can’t Get Autism, So Please Keep Vaccinating Them. Time.com. 2018.
35 Moon-Fanelli AA, Dodman NH, Famula TR, Cottam N. Characteristics of compulsive tail chasing and associated risk factors in Bull Terriers. J Am Vet Med Assoc. 2011;238(7):883-889. doi:10.2460/javma.238.7.883
36 Tsilioni I, Dodman N, Petra AI, et al. Elevated serum neurotensin and CRH levels in children with autistic spectrum disorders and tail-chasing Bull Terriers with a phenotype similar to autism. Transl Psychiatry. 2014;4(10):e466-e466. doi:10.1038/tp.2014.106
37 Reimer M, Troy G, Warnick L. Immune-mediated hemolytic anemia: 70 cases (1988-1996). J Am Anim Hosp Assoc. 1999;35(5):384-391. doi:10.5326/15473317-35-5-384
38 Klag AR, Giger U, Shofer FS. Idiopathic immune-mediated hemolytic anemia in dogs: 42 cases (1986-1990). J Am Vet Med Assoc. 1993;202(5):783-788. http://www.ncbi.nlm.nih.gov/pubmed/8454517. Accessed March 20, 2019.
39 Huang AA, Moore GE, Scott-Moncrieff JC. Idiopathic Immune-Mediated Thrombocytopenia and Recent Vaccination in Dogs. J Vet Intern Med. 2012;26(1):142-148. doi:10.1111/j.1939-1676.2011.00850.x
40 Davidow E, Oncken A. RISK FACTORS FOR DEVELOPMENT OF IMHA – A PROSPECTIVE CASE-CONTROL STUDY. J Vet Emerg Crit Care. 2004;14(S1):S1-S17. doi:10.1111/j.1476-4431.2004.t01-23-04035.x
41 Carr AP, Panciera DL, Kidd L. Prognostic factors for mortality and thromboembolism in canine immune-mediated hemolytic anemia: a retrospective study of 72 dogs. J Vet Intern Med. 16(5):504-509. http://www.ncbi.nlm.nih.gov/pubmed/12322697. Accessed March 20, 2019.
42 Vadalà M. Severe Side Effects of Vaccines in the Veterinary Setting.; 2017. www.mathewsopenaccess.com. Accessed March 20, 2019.
43 Moore GE, HogenEsch H. Adverse Vaccinal Events in Dogs and Cats. Vet Clin North Am Small Anim Pract. 2010;40(3):393-407. doi:10.1016/j.cvsm.2010.02.002
44 Lankenau C. Rabies Vaccinosis in Horses. Innov Vet Care. March 2014.
45 Compton Burnett J. Vaccinosis and Its Cure by Thuja with Remarks on Homoeoprophylaxis. London, U.K.: Homeopathic Publishing Company; 1884.
46 Broadfoot P. Vaccination: A literature review and possible therapies for vaccinosis. J Am Holist Vet Med Assoc. 2017;46:30-39. https://www.ahvma.org/wp-content/uploads/AHVMA-2017-V46-Vaccinosis.pdf. Accessed March 20, 2019.
47 Jordan P. Mark of the Beast: Hidden in Plain Sight. CreateSpace Publishing; 2009.
48 What the Experts Say About Vaccines. https://www.pgferals.org/info/display?PageID=1369. Accessed March 20, 2019.
49 Holistic Vet Expert |About Dr Preston. http://www.holisticvetexpert.com/About-Dr-Preston.html. Accessed March 20, 2019.
50 Vaccination in animals– International Vaccination Newsletter. http://www.whale.to/vaccines/an12.html. Accessed March 20, 2019.
51 Prevent Parvo and Distemper Without Vaccination. https://www.dogsnaturallymagazine.com/prevent-parvo-and-distemper-without-vaccination/. Accessed March 20, 2019.
52 Jordan P. 65 Ways Rabies Vaccination Can Harm Your Dog. Dogs Nat. https://www.dogsnaturallymagazine.com/65-ways-rabies-vaccination-can-harm-your-dog/. Accessed March 20, 2019.
53 Jessop LJ, Murrin C, Lotya J, et al. Socio-demographic and health-related predictors of uptake of first MMR immunisation in the Lifeways Cohort Study. Vaccine. 2010;28(38):6338-6343. doi:10.1016/j.vaccine.2010.06.092
54 Ward PR, Attwell K, Meyer SB, Rokkas P, Leask J. Understanding the perceived logic of care by vaccine-hesitant and vaccine-refusing parents: A qualitative study in Australia. Lee A, ed. PLoS One. 2017;12(10):e0185955. doi:10.1371/journal.pone.0185955
55 Downey L, Tyree PT, Huebner CE, Lafferty WE. Pediatric Vaccination and Vaccine-Preventable Disease Acquisition: Associations with Care by Complementary and Alternative Medicine Providers. Matern Child Health J. 2010;14(6):922-930. doi:10.1007/s10995-009-0519-5
56 Frawley JE, McIntyre E, Wardle J, Jackson D. Is there an association between the use of complementary medicine and vaccine uptake: results of a pilot study. BMC Res Notes. 2018;11(1):217. doi:10.1186/s13104-018-3323-8
57 Frawley JE, Foley H, McIntyre E. The associations between medical, allied and complementary medicine practitioner visits and childhood vaccine uptake. Vaccine. 2018;36(6):866-872. doi:10.1016/j.vaccine.2017.12.036
58 Wardle J, Frawley J, Steel A, Sullivan E. Complementary medicine and childhood immunisation: A critical review. Vaccine. 2016;34(38):4484-4500. doi:10.1016/j.vaccine.2016.07.026
59 Ernst E. Rise in popularity of complementary and alternative medicine: reasons and consequences for vaccination. Vaccine. 2001;20 Suppl 1:S90-3; discussion S89. http://www.ncbi.nlm.nih.gov/pubmed/11587822. Accessed March 20, 2019.
60 Attwell K, Ward PR, Meyer SB, Rokkas PJ, Leask J. “Do-it-yourself”: Vaccine rejection and complementary and alternative medicine (CAM). Soc Sci Med. 2018;196:106-114. doi:10.1016/J.SOCSCIMED.2017.11.022
61 Gleberzon B, Lameris M, Schmidt C, Ogrady J. On Vaccination & Chiropractic: when ideology, history, perception, politics and jurisprudence collide. J Can Chiropr Assoc. 2013;57(3):205-213. http://www.ncbi.nlm.nih.gov/pubmed/23997246. Accessed March 20, 2019.
62 Campbell JB, Busse JW, Injeyan HS. Chiropractors and vaccination: A historical perspective. Pediatrics. 2000;105(4):E43. doi:10.1542/PEDS.105.4.E43
63 Zuzak TJ, Zuzak-Siegrist I, Rist L, Staubli G, Simoes-Wüst AP. Attitudes towards vaccination: users of complementary and alternative medicine versus non-users. Swiss Med Wkly. 2008;138(47-48):713-718. doi:2008/47/smw-12423
64 Lehrke P, Nuebling M, Hofmann F, Stoessel U. Attitudes of homoeopathic physicians towards vaccination. Vaccine. 2001;19(32):4859-4864. http://www.ncbi.nlm.nih.gov/pubmed/11535339. Accessed March 20, 2019.
65 Buehning LJ, Peddecord KM. Vaccination Attitudes and Practices of Integrative Medicine Physicians. Altern Ther Health Med. 2017;23(1):46-54. http://www.ncbi.nlm.nih.gov/pubmed/28160764. Accessed March 20, 2019.
66 Busse JW, Kulkarni A V, Campbell JB, Injeyan HS. Attitudes toward vaccination: a survey of Canadian chiropractic students. CMAJ. 2002;166(12):1531-1534. http://www.ncbi.nlm.nih.gov/pubmed/12074119. Accessed March 20, 2019.
67 Omer SB, Salmon DA, Orenstein WA, deHart MP, Halsey N. Vaccine Refusal, Mandatory Immunization, and the Risks of Vaccine-Preventable Diseases. N Engl J Med. 2009;360(19):1981-1988. doi:10.1056/NEJMsa0806477
68 People’s Dispensary for Sick Animals (PDSA). PAW Report 2018: PDSA Animal Wellbeing.; 2018. https://www.pdsa.org.uk/media/4371/paw-2018-full-web-ready.pdf?awc=7028_1552405061_745c448d2576d55438919a647c24e219&utm_source=Affiliate_Window&utm_medium=Affiliate_Marketing&utm_campaign=Skimlinks. Accessed March 12, 2019.
69 Belshaw Z, Robinson NJ, Dean RS, Brennan ML. Motivators and barriers for dog and cat owners and veterinary surgeons in the United Kingdom to using preventative medicines. 2018. doi:10.1016/j.prevetmed.2018.03.020
70 Bottoms K, Trotz-Williams L, Hutchison S, et al. An Evaluation of Rabies Vaccination Rates among Canines and Felines Involved in Biting Incidents within the Wellington-Dufferin-Guelph Public Health Department. Zoonoses Public Health. 2014;61(7):499-508. doi:10.1111/zph.12101
71 Sánchez-Vizcaíno F, Muniesa A, Singleton DA, et al. Epidemiology and Infection Use of vaccines and factors associated with their uptake variability in dogs, cats and rabbits attending a large sentinel network of veterinary practices across Great Britain. 2018. doi:10.1017/S0950268818000754
72 Goyen KA, Wright JD, Cunneen A, Henning J. Playing with fire – What is influencing horse owners’ decisions to not vaccinate their horses against deadly Hendra virus infection? Munderloh UG, ed. PLoS One. 2017;12(6):e0180062. doi:10.1371/journal.pone.0180062
73 Gehrig A-C, Hartmann K, Günther F, Klima A, Habacher G, Bergmann M. A survey of vaccine history in German cats and owners’ attitudes to vaccination. J Feline Med Surg. 2019;21(2):73-83. doi:10.1177/1098612X18759838
74 Habacher G, Gruffydd-Jones T, Murray J. Use of a web-based questionnaire to explore cat owners’ attitudes towards vaccination in cats. Vet Rec. 2010;167:122-127. doi:10.1136/vr.b4857
Source URL: https://www.veterinarypracticenews.ca/anti-vaccine-june-2019/
Copyright ©2020 Veterinary Practice News unless otherwise noted.