What is the management for an animal bite?

Management of Animal Bites

For animal bite wounds, immediately irrigate copiously with sterile normal saline, provide wound care with selective closure (facial wounds only), administer amoxicillin-clavulanate for 3-5 days for high-risk wounds, update tetanus prophylaxis, and assess rabies risk based on the biting animal's observability. 1, 2

Immediate Wound Care

• Irrigate the wound copiously with sterile normal saline using a 20-mL or larger syringe to remove debris and reduce bacterial load 3, 1
• Avoid high-pressure irrigation as this may drive bacteria deeper into tissue layers 1
• Debride necrotic tissue cautiously to mechanically reduce pathogen burden 1
• Explore the wound for foreign bodies, tendon involvement, or bone penetration 3

Wound Closure Decision

• Close facial wounds primarily after meticulous irrigation, debridement, and prophylactic antibiotics for optimal cosmetic outcomes 2, 1
• Do not close non-facial wounds; approximate edges with Steri-Strips if needed 2, 1
• Never close infected wounds or wounds presenting late (>8 hours) 1

Antibiotic Prophylaxis

Administer preemptive antibiotics for 3-5 days in these high-risk scenarios: 2, 1

• Cat bites (30-50% infection rate) 1
• Hand wounds 1, 2
• Deep wounds or puncture wounds 3, 4
• Wounds potentially penetrating periosteum or joint capsule 2
• Immunocompromised patients, asplenic patients, or those with advanced liver disease 2
• Wounds with associated severe cellulitis 1

First-line antibiotic: Amoxicillin-clavulanate (covers Pasteurella, Staphylococcus, Streptococcus, and anaerobes) 2, 3

Alternative oral regimens for penicillin allergy: 2

• Doxycycline (excellent Pasteurella coverage)
• Fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin) plus metronidazole or clindamycin

IV options for severe infections: 2

• Ampicillin-sulbactam or piperacillin-tazobactam (first-line)
• Second-generation cephalosporins (cefoxitin)
• Carbapenems (ertapenem, imipenem, meropenem)

Tetanus Prophylaxis

• Administer tetanus toxoid (0.5 mL IM) if last vaccination was >10 years ago or status unknown 2
• Prefer Tdap over Td if patient has not previously received Tdap 2

Rabies Risk Assessment and Management

For dog, cat, or ferret bites: 1, 2

• If the animal is healthy and available: Confine and observe daily for 10 days without administering rabies vaccine to the animal 1
• Do not start human rabies prophylaxis during the observation period unless the animal develops signs of illness 2
• If the animal develops signs suggestive of rabies, euthanize immediately and submit the head for brain examination 1
• If the animal is stray, unwanted, or cannot be observed: Euthanize immediately and submit head for rabies testing 1

For wild animal or bat bites: 1

• Euthanize the animal immediately and submit for rabies testing
• Consult local health officials regarding need for post-exposure prophylaxis 2

If rabies prophylaxis is indicated: 2, 3

• Previously unvaccinated persons receive both rabies immunoglobulin (HRIG) and vaccine
• Vaccine schedule: Days 0,3,7,14, and 28 3

Follow-Up Protocol

• Schedule follow-up within 48-72 hours to assess for infection and wound healing 2
• Instruct patients to return immediately for signs of infection: increasing pain, redness, swelling, purulent drainage, fever, or lymphangitis 1
• Hand wounds require particularly close follow-up due to higher complication risk 2

Special Considerations for Human Bites

• Human bites have 20-25% infection rate and require similar management principles 1, 5
• Clenched-fist injuries demand expert hand evaluation for joint capsule or bone penetration 5
• Common pathogens include Streptococcus (50%), Staphylococcus aureus (40%), and Eikenella corrodens (30%) 1
• Consider post-exposure prophylaxis for HBV, HCV, and HIV based on exposure circumstances 1, 5

Common Pitfalls to Avoid

• Do not universally prescribe antibiotics for all bite wounds—target high-risk scenarios only 1
• Do not close non-facial bite wounds as this increases infection risk 2
• Do not start rabies vaccine in the biting animal during the 10-day observation period as this confuses clinical assessment 1
• Do not delay rabies prophylaxis if indicated, even with late presentation, as incubation periods exceeding 1 year have been documented 2