Dog bite risk and prevention: The role of breed (2023)

Literature review

May 15, 2014

This peer-reviewed summary has been prepared by the American Veterinary Medical Association Animal Welfare Division. While principally a review of the scientific literature, it may also include information gleaned from proprietary data, legislative and regulatory review, market conditions, and scholarly ethical assessments. It is provided as information and its contents should not be construed as official AVMA policy. Mention of trade names, products, commercial practices or organizations does not imply endorsement by the American Veterinary Medical Association.

PDF version

Breeds implicated in serious bite injuries

In a range of studies, the breeds found to be highly represented in biting incidents were German Shepherd Dog,^{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,50} mixed breed,^{1,4,6,8,10,11,12,19,17, 20,50} pit bull type,^{5,9,13,16,21,20,22,23,24,25,26,27} Rottweiler,^{15,18,22,24,25,28} Jack Russell Terrier,^21,25,26 and others (Chow Chow,^7,23 Spaniel,^14,26 Collie,^3,29 Saint Bernard,²⁰ and Labrador Retriever²).

If you consider only the much smaller number of cases that resulted in very severe injuries or fatalities,^21,23 pit bull-type dogs are more frequently identified. However this may relate to the popularity of the breed in the victim's community, reporting biases and the dog's treatment by its owner (e.g., use as fighting dogs²¹). It is worth noting that fatal dog attacks in some areas of Canada are attributed mainly to sled dogs and Siberian Huskies,⁵⁶ presumably due to the regional prevalence of these breeds. See Table 1 for a summary of breed data related to bite injuries.

Controlled studies

The prevalence of particular dog breeds can also change rapidly over time, often influenced by distinct peaks of popularity for specific breeds. It seems that increased popularity is sometimes followed by increases in bite reports in some large breeds. For example there was a distinct peak in American Kennel Club registration of Rottweilers³⁰ between 1990 and 1995, and they come at the top of the list of 'biting breeds' for the first time in studies of bites causing hospitalization in the late 90s and early 2000s.^25,28,15,58 While it must be noted that other fad breeds such as Dalmatians and Irish setters do not seem to make similar appearances, any estimate of breed-based risk must take into account the prevalence of the breed in the population at the time and place of serious biting events.^17,31

For example, researchers can compare well-documented bite cases with matched control households. Using this method, one study found that the breeds disproportionately involved in bite injuries requiring medical attention in the Denver area (where pit bull types are not permitted) were the German Shepherd Dog and Chow Chow.⁶⁴

Other studies use estimates of breed prevalence that do not relate specifically to the households where the bites occurred, such as general community surveys, breed registries, licensed dogs or animal shelter populations (See Table 2.). A study in Rome, Italy where molloser dogs like mastiff are reputed to be the most dangerous dogs, found they were not disproportionately involved in biting incidents when taking into account their prevalence in the community.³² These prevalence referenced studies attribute higher risk to the German Shepherd Dog and crosses^{60,61,62,63,64}, and various other breeds (mixed breed,^62,63 Cocker spaniel,^61,65 Chow Chow,^64,65 Collie,⁶¹ Doberman,⁶⁰ Lhasa Apso,^44,65 Rottweiler,⁴⁹ Springer Spaniel,⁴³ Shih Tsu,⁴³ and Poodle⁶²).

Aggressive breeds

Based on behavioral assessments and owner surveys the breeds that were more aggressive towards people were small to medium-sized dogs such as the collies, toy breeds and spaniels.^{33,34,35,36,37} For example, a survey of general veterinary clientele in Canada (specifically practices in New Brunswick, Novia Scotia, and Prince Edward Island) identified Lhasa Apso, Springer spaniel and Shih Tsu as more likely to bite.⁴³

While small dogs may be more aggressive their size means they are less likely to inflict serious bite injury except on vulnerable individuals or as part of a pack attack, which also allows dogs to seriously or injury healthy older children or adults.^38,39 Referrals for aggression problems more closely approximate the breeds implicated in serious bite attacks, probably because owners are more likely to seek treatment for aggression in dogs that are large enough to be dangerous. Larger dogs (regardless of breed) are implicated in more attacks on humans⁴⁰ and other dogs.⁴¹

Certain large breeds are notably under-represented in bite statistics such as large hounds and retrievers (e.g., Labrador Retrievers and Golden Retrievers)^35,43—although even these breeds may have known aggressive subtypes.⁴² Results relating to German Shepherd Dogs are mixed,^36,43 suggesting there may be particularly high variability in this breed, perhaps depending on regional subtypes or ownership factors.

Pit bull types

Owners of pit bull-type dogs deal with a strong breed stigma,⁴⁴ however controlled studies have not identified this breed group as disproportionately dangerous. The pit bull type is particularly ambiguous as a "breed" encompassing a range of pedigree breeds, informal types and appearances that cannot be reliably identified. Visual determination of dog breed is known to not always be reliable.⁴⁵ And witnesses may be predisposed to assume that a vicious dog is of this type.

It should also be considered that the incidence of pit bull-type dogs' involvement in severe and fatal attacks may represent high prevalence in neighborhoods that present high risk to the young children who are the most common victim of severe or fatal attacks. And as owners of stigmatized breeds are more likely to have involvement in criminal and/or violent acts⁴⁶—breed correlations may have the owner's behavior as the underlying causal factor.

Breed bans

Most serious dog bite injuries (requiring hospital treatment) in the United States are the victim being a young child⁵⁴ and the dog being un-neutered and familiar (belonging to the family, a family friend or neighbor).^32,47,48,54 Therefore responsible ownership and supervision is key to minimizing the risk of dog bites in communities.

While some study authors suggest limiting ownership of specific breeds might reduce injuries (e.g., pit bull type,⁴⁹ German Shepherd Dog⁵⁰) it has not been demonstrated that introducing a breed-specific ban will reduce the rate or severity of bite injuries occurring in the community.^8,51 Strategies known to result in decreased bite incidents include active enforcement of dog control ordinances,⁵² and these may include ordinances relating to breed.⁵³

Conclusion

Maulings by dogs can cause terrible injuries⁴⁷ and death—and it is natural for those dealing with the victims to seek to address the immediate causes. However as Duffy et al (2008) wrote of their survey based data: "The substantial within-breed variation…suggests that it is inappropriate to make predictions about a given dog's propensity for aggressive behavior based solely on its breed." While breed is a factor, the impact of other factors relating to the individual animal (such as training method, sex and neutering status), the target (e.g. owner versus stranger), and the context in which the dog is kept (e.g. urban versus rural) prevent breed from having significant predictive value in its own right. Also the nature of a breed has been shown to vary across time, geographically, and according to breed subtypes such as those raised for conformation showing versus field trials.³⁷

Given that breed is a poor sole predictor of aggressiveness and pit bull-type dogs are not implicated in controlled studies it is difficult to support the targeting of this breed as a basis for dog bite prevention. If breeds are to be targeted a cluster of large breeds would be implicated including the German shepherd and shepherd crosses and other breeds that vary by location.

See also:

National Animal Control Association Guideline Statement: "Dangerous and/or vicious animals should be labeled as such as a result of their actions or behavior and not because of their breed."

Summary tables

Table 1
Studies of serious dog bite injury by breed

Table 2
Studies of serious dog bite injury by breed taking into account breed prevalence

References

1. Morton C. Dog bites in Norfolk, VA. Health Seru Rep, 1973;88:59-65.
2. Chait LA,Spitz L. Dogbite injuries in children. S Afr Med J 1975;49:718-720.
3. Maetz, M. Animal bites, a public health problem in Jefferson County, Alabama. Public Health Rep 1979;94: 528-534.
4. Levene S. Dog bites to children. BMJ 1991;303:466.
5. Avner JR, Baker MD. Dog bites in urban children. Pediatrics. 1991;88:55-57.
6. Jarrett P. Which dogs bite? Arch Emerg Med 1991;8:33–35.
7. Patrick GR, O'Rourke KM. Dog and cat bites: epidemiologic analyses suggest different prevention strategies. Public Health Rep 1998;113:252257.
8. Klaassen B, Buckley JR, Esmail A. Does the Dangerous Dogs Act protect against animal attacks: a prospective study of mammalian bites in the accident and emergency department. Injury 1996; 27: 89-91.
9. Meade, P. Police and domestic dog bite injuries: What are the differences? What are the implications about police dog use? Injury Extra 2006;37:395-401.
10. Moore DA, Sischo WM, Hunter A, et al. Animal bite epidemiology and surveillance for rabies postexposure prophylaxis. J Am Vet Med Assoc 2000;217:190–194.
11. Mendez Gallart R, Gomez Tellado M, Somoza Argibay I, Liras Munoz J, Pais Pineiro E, Vela Nieto D. Dog bite related injuries treated in a pediatric surgery department: analysis of 654 cases in 10 years. An Esp Pediatr. 2002;56:425–429.
12. Schalamon J. Analysis of dog bites in children who are younger than 17 years. Pediatrics 2006;117:374–379.
13. Wake AF. The Aetiology of Dog Bites in New Zealand, [MSc thesis], Palmerston North: Massey University, 2005.
14. Reisner, IR. Assessment, management, and prognosis of canine dominated-related aggression. The Veterinary Clinics of North America Small Animal Practice 1997;27:479–495.
15. Benson LS, Edwards SL, Schiff AP, et al. Dog and cat bites to the hand: treatment and cost assessment. J Hand Surg [Am] 2006; 31: 468-473.
16. Ashby K. Dog bites. Victorian Injury Surveillance System. Hazard 1996; 26: 7-13.
17. Wake A, Minot E, Stafford K, Perry P. A survey of adult victims of dog bites in New Zealand. New Zeal Vet J 2009; 57:364-369.
18. Pfortmueller CA, Efeoglou A, Furrer H, Exadaktylos AK. Dog Bite Injuries: Primary and Secondary Emergency Department Presentations—A Retrospective Cohort Study. Sci World J 2013;2013:1-6.
19. Daniels TJ. A study of dog bites on the Navajo reservation. Public Health Rep 1986;101:50-59.
20. Reisner IR, Shofer FS, Nance NL. Behavioral assessment of child-directed canine aggression. Inj Prev 2007;13:348-351.
21. Wright JC. Severe attacks by dogs: characteristics of the dogs, the victims, and the attack settings. Public Health Rep 1985;100:55–61.
22. Shewell PC, Nancarrow JD. Dogs that bite. BMJ 1997;303:1512–13.
23. Sacks JJ, Sinclair L, Gilchrist J, Golab GC, Lockwood R. Breeds of dogs involved in fatal human attacks in the United States between 1979 and 1998. J Am Vet Med Assoc 2000; 217: 836–840.
24. Blocker DE. Dog bite rates and biting dog breeds in Texas, 1995-1997. Masters Thesis 2000.
25. Kaye AE, Belz JM, Kirschner RE. Pediatric Dog Bite Injuries: A 5 Year Review of the Experience at the Children's Hospital of Philadelphia. Plastic and Reconstructive Surgery 2009;124:551-558.
26. Horswell BB, Chahine CJ. Dog bites of the face, head and neck in children. West Virg Med J 2010;107:24-27
27. Kasbekar AV, Garfit H, Duncan C, Mehta B, Davies K, Narasimhan G, Donne A. Dog bites to the head and neck in children; an increasing problem in the UK. Clin Otolaryngology 2013;38:259-262.
28. Thompson P. Aggression Effects - From a Human Perspective and Solutions. Urban Animal anagement Conference Proceedings 2004.
29. O'Sullivan E. Characteristics of 234 dog bite incidents in Ireland during 2004 and 2005. Vet Rec 2008;163:37-42.
30. Herzog H. Forty-two Thousand and One Dalmatians: Fads, Social Contagion, and Dog Breed Popularity. Society and Animals 2006;4:383-398.
31. Cunningham, L. The Case Against Dog Breed Discrimination By Homeowners' Insurance Companies. Connecticut Insurance Law Journal 2004;11:61.
32. Maragliano L, Ciccone G, Fantini C, Petrangeli C, Saporito G, Di Traglia M, Natoli E. Biting dogs in Rome (Italy). Int J pest manag 2007;4:329-334.
33. Fatjó J, Amat M, Mariotti VM, Torre JLR, Manteca X. Analysis of 1040 cases of canine aggression in a referral practice in Spain. J Vet Behav 2007; 2:158-65.
34. Duffy, DL., Hsu, Y. Serpell, JA. Breed differences in canine aggression. Appl Anim Behav Sci 2008;114:441–460.
35. Draper, T.W., Canine analogs of human personality factors. J Gen Psyc 1995;122: 241–252.
36. Lund JD, Agger JF, Vestergaard KS. Reported behaviour problems in pet dogs in Denmark: age distribution and influence of breed and gender. Preventative Vet med 1996;28:33-48
37. Duffy D, Yuying H, Serpell J. Breed differences in canine aggression. Appl Anim Behav Sci 2008;114.3: 441-460.
38. Borchelt PL, Lockwood R, Beck AM, Voith VL. Attacks by packs of dogs involve predation on human beings. Public Health Reports 1983;98:57-66.
39. Kneafsey B, Condon KC. Severe dog-bite injuries, introducing the concept of pack attack: A literature review and seven case reports. Injury. 1995;26:37–41.
40. Harris D, Imperato PJ, Oken B. Dog bites—an unrecognized epidemic. Bull NY Acad Med 1974;50:981–1000.
41. Roll, A., Unshelm, J. Aggressive conflicts amongst dogs and factors affecting them. Appl Anim Behav Sci. 1997;52:229–242.
42. van den Berg, L., Schilder, M.B.H., Knol, B.W. Behaviour genetics of canine aggression: behavioural phenotyping of Golden Retrievers by means of an aggression test. Behav Gen 2003;33:469–483.
43. Guy, N, Canine household aggression in the caseload of general veterinary practitioners in Maritime Canada, Master of Science thesis, Atlantic Veterinary College, University of Prince Edward Island, 1999
44. Twining, H., Arluke, A. Patronek, G. Managing stigma of outlaw breeds: A case study of pit bull owners. Society and Animals 2001;8:1-28.
45. Voith VL, Ingram E, Mitsouras K. Comparison of adoption agency breed identification and DNA breed identification of dogs. J Appl Anim Welf Sci 2009;12:253–262.
46. Ragatz L, Fremouw W, Thomas T, McCoy K. Vicious dogs: the antisocial behaviors and psychological characteristics of owners. Journal of Forensic Sciences 2009;54:699-703
47. Loewe CL, Francisco JD, Bechinski J. Pitbull mauling deaths in Detroit. The American Journal of Forensic Medicine and Pathology 2007;28:356-360.
48. Monroy A, Behar P, Nagy M, Poje C, Pizzuto M, Brodsky L. Head and neck dog bites in children. Otolaryngol. Head Neck Surg 2009;140:354–357
49. Thompson PG. The public health impact of dog attacks in a major Australian city. Med J Aust 1997;167:129-32.
50. Greenhalgh C, Cockington R, Raftos I. An epidemiological survey of dog bites presenting to the emergency department of a children's hospital . J Paediatr Child Health 1991; 27: 171-174.
51. Raghavan M, Martens P. Chateau D, Burchill C. Effectiveness of breed-specific legislation in decreasing the incidence of dog-bite injury hospitalisations in people in the Canadian province of Manitoba. Inj Prev 2013;19:177-183.
52. Clarke NM. A survey of urban Canadian animal control practices : the effect of enforcement and resourcing on the reported dog bite rate, Master of Science – MSc 2009
53. Villalbí JR, Cleries M, Bouis S, Peracho V, Duran J, Casas C. "Decline in hospitalisations due to dog bite injuries in Catalonia, 1997–2008. An effect of government regulation?. Inj Prev 2010;16:408-410.
54. Ordog GJ. Warning to dog owners. Can Family Physic 1984;30:1056.
55. Healey D. Fatal dog bites in New Zealand. J New Zeal Med Assoc 2007;120:1259.
56. Raghavan M. Fatal dog attacks in Canada, 1990–2007. Can Vet J. 2008;49:577–581.
57. Ashby K. Dog bites. Victorian Injury Surveillance System. Hazard 1996; 26: 7-13.
58. Lang ME, Klassen T. Dog bites in Canadian children: a five-year review of severity and emergency department management. Can J Emerg Med. 2005;7:309–314.
59. Dwyer JP, Douglas TS, van As AB. Dog bites injuries in children—a review of data from a South Africa paediatric trauma unit. 2007;97:597–600.
60. Berzon DR. The animal bite epidemic in Baltimore, Maryland: review and update. Am I Public Health. 1978;68:593-595.
61. Hanna, TL, Selby LA. Characteristics of the human and pet populations in animal bite incidents recorded at two Air Force bases. Public Health Rep. 1981;96:580-584.
62. Lauer EA, White WC, Lauer BA. Dog bites: a neglected problem in accident prevention. AJDC. 1982;136:202-204.
63. Szpakowski NM, Bonnett BN, Martin SW. An epidemiological investigation into the reported incidents of dog biting in the Cityof Guelph. Can Vet J 1989;30:937–942.
64. Gershman KA, Sacks JJ, Wright JC. Which dogs bite: a case-control study of risk factors. Pediatrics 1994;93:913-917.
65. Castelein C, Klouda J, Hirsch H. The bite case scenario—it is not what you think. In: WFHS newsletter. Madison, Wis: Wisconsin Humane Society, 1996;Sep:12–14. Cited in: Overall KL, Love M. Dog bites to humans: demography, epidemiology, injury, and risk. J Am Vet Med Assoc 2001;218:1923-1934.