What is the recommended management for a rat scratch?

Management of Rat Scratches

Immediate and thorough washing of the scratch wound with soap and water followed by application of a virucidal agent such as povidone-iodine solution is the most important first step in managing a rat scratch. 1

Initial Wound Management

• Immediate wound cleansing is crucial and has been shown in animal studies to markedly reduce the likelihood of infection 1
• Wear protective gloves (rubber, latex, vinyl, or nitrile) when cleaning the wound 1
• Clean the wound with soap and water, followed by application of a virucidal agent such as povidone-iodine solution 1
• Avoid high-pressure irrigation as it may spread bacteria into deeper tissue layers 1
• Do not suture the wound if possible, as this may increase infection risk 1

Risk Assessment

• Consider the circumstances of the scratch (provoked vs. unprovoked) as unprovoked attacks are more likely to indicate the animal might be rabid 1
• Assess the wound location - scratches on hands, feet, areas near joints, face, and genitals are at higher risk for complications 1
• Evaluate the depth of the wound - deeper wounds have higher infection risk 1
• Consider the time elapsed since injury - wounds presenting >24 hours after injury without signs of infection may not require antibiotics 1

Infection Prevention

• Tetanus prophylaxis should be administered if vaccination status is not current or unknown 1
• While universal antibiotic prophylaxis is not recommended, antibiotics should be considered for:
  • Deep wounds 1
  • Wounds in critical areas (hands, feet, face, near joints, genitals) 1
  • Persons with elevated infection risk (immunocompromised, diabetic) 1
  • Persons with implants such as artificial heart valves 1
• When indicated, antibiotics should be given for 3-5 days 1

Potential Pathogens and Antibiotic Selection

• Rat scratches can be infected with various pathogens including Streptobacillus moniliformis (causing rat bite fever), Staphylococcus spp., Streptococcus spp., and other organisms 1, 2
• If antibiotics are indicated, they should cover both aerobic and anaerobic organisms 1
• Appropriate options include:
  • β-lactam/β-lactamase combinations (e.g., ampicillin-sulbactam) 1
  • Amoxicillin-clavulanate 1
  • Second-generation cephalosporins 1

Rabies Considerations

• Consult local health department about rabies risk in wild or feral rats in your geographic area 1
• If rabies exposure is suspected:
  • Rabies post-exposure prophylaxis includes wound treatment and administration of both rabies immune globulin (RIG) and vaccine 1
  • The first dose should be given as soon as possible after exposure 1
  • Additional doses should be given on days 3,7,14, and 28 after the first vaccination 1

Follow-up and Monitoring

• Follow up within 24 hours either by phone or office visit to assess for signs of infection 1
• Monitor for complications such as:
  • Local infection (redness, swelling, increasing pain, purulent discharge) 1
  • Rat bite fever (fever, myalgia, headache, rash, polyarthritis) which can occur even without fever 2
  • Systemic infection (fever, chills, lymphadenopathy) 2

Common Pitfalls to Avoid

• Delaying wound cleansing - immediate cleansing is critical 1
• Closing wounds with sutures - this can increase infection risk 1
• Failing to consider rabies prophylaxis when appropriate 1
• Overlooking tetanus prophylaxis 1
• Not recognizing rat bite fever, which can be potentially lethal but is easily treatable 2
• Using high-pressure irrigation which can drive bacteria deeper into tissues 1