Should post-exposure prophylaxis (PEP) including rabies vaccine be administered after a scratch from a domestic dog that is still alive 10 days later?

Rabies Post-Exposure Prophylaxis for Dog Scratch

Post-exposure prophylaxis (PEP) is NOT recommended for a scratch from a domestic dog that remains healthy and alive after a 10-day observation period. 1

Assessment of Exposure Risk

• A healthy domestic dog that scratches a person should be confined and observed for 10 days 1
• Dogs that remain alive and healthy 10 days after exposure would not have been shedding rabies virus in their saliva at the time of the incident and would not have been infectious 1
• The 10-day observation period is sufficient to reliably determine the risk of rabies exposure for the person who was scratched 1

Key Decision Factors

• Type of exposure: Scratches from dogs carry significantly lower risk than bites, as transmission typically requires introduction of infected saliva into an open wound 2
• Health status of the animal: Any illness in the dog during the confinement period should be evaluated by a veterinarian and reported immediately to the local public health department 1
• Vaccination status of the dog: A dog with a history of current rabies vaccination is unlikely to become infected with rabies 1
• Circumstances of the incident: An unprovoked attack might be more likely to indicate rabies than a provoked interaction 1
• Local rabies epidemiology: The likelihood of rabies in domestic dogs varies regionally 1

Management Algorithm

1. Immediate wound care:

   • Thoroughly wash and flush the scratch with soap and water for about 15 minutes 2, 3
   • Apply an iodine-containing or similarly virucidal topical preparation to the wound where available 2
   • Assess need for tetanus prophylaxis and measures to control bacterial infection 1

2. Observation of the dog:

   • Confine and observe the domestic dog for 10 days 1
   • Monitor for any signs of illness or abnormal behavior 1

3. PEP decision:

   • If dog remains healthy throughout 10-day observation: No PEP is required 1, 4
   • If dog develops signs suggestive of rabies: Immediately begin PEP, euthanize the animal, and submit for rabies testing 1, 4
   • If dog's status cannot be verified: Consult public health officials 4

Special Considerations

• The essential components of rabies PEP (when indicated) include wound treatment and, for previously unvaccinated persons, administration of both rabies immune globulin (RIG) and vaccine 1
• Administration of rabies PEP is a medical urgency, not a medical emergency, but decisions should not be delayed if exposure is confirmed 1
• In areas where canine rabies is not endemic (including most of the United States), the risk of rabies from domestic dogs is extremely low 1
• Failures of appropriate PEP are extremely rare when administered according to guidelines 5, 6

Common Pitfalls to Avoid

• Unnecessary PEP: Administering PEP when not indicated exposes patients to potential vaccine side effects and wastes resources 2
• Delayed reporting: Any illness in the dog during the observation period must be promptly reported 1
• Inadequate wound care: Thorough wound cleansing alone can markedly reduce the likelihood of rabies transmission 1, 7
• Ignoring local epidemiology: The risk assessment should consider the prevalence of rabies in the local dog population 1

Remember that if the dog remains healthy throughout the 10-day observation period, this confirms the animal was not shedding rabies virus at the time of the scratch, making PEP unnecessary 1.