II. Epidemiology

  1. Incidence in United States: 4 to 4.5 Million bites per year
    1. Rate: 103-118 per 100,000 people in U.S.
    2. Dog Bites account for 80-90% of Animal Bites in U.S.
    3. Unprovoked Dog Bites account for 50% of events
    4. Dogs are known to the victim in 70% of Dog Bite cases
  2. Mortality: >12 per year in U.S. (most are children)
    1. Pit bulls accounted for 44% fatalities 1979-1988
    2. Rottweilers are also responsible for many of the fatalities
  3. Infection rate: 15-20%
  4. Children are more likely than adults to sustain bites

III. Risk Factors: Bites associated with breed

  1. Aggressive dogs
    1. Dogs associated with fatal attacks
      1. Pit Bull
      2. Malamute
      3. Chow-Chow
      4. Rottweiler
      5. Siberian Husky
      6. German Shepherd
      7. Wolf hybrids
    2. Other Aggressive dogs
      1. Bull terrier
      2. Cocker spaniel
      3. Collie
      4. Doberman Pinscher
      5. Great Dane
  2. Less aggressive breeds (Family dogs)
    1. Boxer
    2. Dalmatian
    3. English Setter
    4. English Springer
    5. Golden Retriever
    6. Irish Setter
    7. Labrador Retriever
    8. Spaniel

IV. Pathophysiology

  1. Crush or avulsion injuries are more typical from Dog Bite
  2. Jaw of a dog can generate pressures up to 450 psi (some report up to 1800 psi)
    1. Occult Fractures may occur with high compression forces

V. Signs: Distribution

  1. Head and Neck (15% of Dog Bites)
    1. Typical site for Dog Bites in young children, especially ears
  2. Extremities (arms account for 60% of Dog Bites)
    1. Typical site for Dog Bites in adolescents and adults

VI. Management

  1. See Animal Bite for irrigation and general management
  2. See Dog Bite Infection for antibiotic selection
  3. Update Tetanus Vaccination as needed
  4. Confirm dog has up to date Vaccinations including Rabies
    1. Start Rabies Prophylaxis if Rabies status cannot be confirmed
  5. Wound Repair
    1. Safe to repair all Dog Bite wounds (regardless of location) presenting within 8 hours of bite injury
      1. Infection rates increase significantly after 8 hours (22% infection rate versus 4.5%)
      2. Bite wounds treated with primary closure should be treated with antibiotics (see Dog Bite Infection)
    2. Inform patient of risks of infection, closure options
      1. Primary closure results in significantly better cosmetic results than secondary closure
      2. Dog Bite Infection rates are similar regardless of management
        1. Primary closure (6-9.7%)
        2. Secondary closure (6.9%)
    3. References
      1. Chen (2000) Acad Emerg Med 7(2): 157-61 [PubMed]
      2. Paschos (2014) Injury 45(1): 237-40 [PubMed]

VII. Complications: Dog Bite Infection

  1. Pasteurella Canis most common infection (aerobic infection)
  2. Other common aerobic infections
    1. Staphylococcus
    2. Streptococcus
  3. Other common anaerobic infections
    1. Fusobacterium
    2. Bacteroides
    3. Prevotella
    4. Porphyromonas
    5. Propionibacterium

VIII. Disposition

  1. Outpatient Wound Check in 24-48 hours Indications
    1. Usually indicated over inpatient care
    2. All hand wounds should be rechecked

IX. Prevention: Dog Bites

  1. Keep dogs updated on Vaccinations (and other routine veterinary care)
  2. Socialize dogs to children
  3. Neutered dogs are less likely to bite
  4. Do not leave young children alone with a dog
  5. Exercise caution with ill pets or those in pain (more likely to bite)

X. Prevention: Lessons for Children

  1. Do not approach an unfamiliar dog
  2. Do not disturb a dog eating or sleeping
  3. Do not disturb a dog caring for puppies
  4. When approached by a dog
    1. Never scream near a dog
    2. Never run from a dog
      1. Be still (Like a tree)
      2. If you fall, become a log
    3. Allow the dog to first sniff you before petting him
    4. Do not make direct eye contact with the dog
  5. Reporting guidelines
    1. Report Dog Bites to an adult immediately
    2. Report stray dogs or unusual behavior immediately

XI. Resources

  1. Dog Bite Prevention (American Veterinary Medical Association)
    1. https://www.avma.org/public/Pages/Dog-Bite-Prevention.aspx

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