What is the recommended post-exposure prophylaxis (PEP) for a 21-month-old child who has been scratched by a vaccinated cat?

Post-Exposure Prophylaxis for Cat Scratch in 21-Month-Old Child

For a 21-month-old child scratched by a vaccinated cat, confine and observe the cat for 10 days without initiating rabies post-exposure prophylaxis, provided the cat is healthy and available for observation. 1, 2

Immediate Wound Management

• Thoroughly wash and flush the scratch wound immediately with soap and water for approximately 15 minutes to reduce infection risk and potential rabies transmission 2
• Irrigate with povidone-iodine solution after soap and water cleansing, as this virucidal agent further reduces rabies risk 2
• Examine the wound carefully for depth, tendon involvement, or other complications 2

Rabies Risk Assessment and Decision Algorithm

The key decision point is whether the cat can be confined and observed for 10 days:

If the Cat is Available and Healthy:

• Confine and observe the cat for 10 days without initiating rabies prophylaxis 1, 2
• A cat that remains healthy and alive for 10 days after the scratch would not have been shedding rabies virus at the time of the exposure 1
• The cat should be evaluated by a veterinarian at the first sign of illness during confinement 1
• A vaccinated cat with continuously current vaccination history is unlikely to become infected with rabies 1

Initiate Immediate Rabies PEP If:

• The cat is stray or unwanted and cannot be confined for observation 1, 2
• The cat dies or develops illness before completing the 10-day observation period 2
• The cat shows signs suggestive of rabies during the observation period (such as unexplained aggressive behavior or sudden behavioral change) 1, 3
• The cat is unavailable for testing 1

Rabies Post-Exposure Prophylaxis Regimen (If Indicated)

For a previously unvaccinated 21-month-old child, the regimen consists of:

• Human Rabies Immune Globulin (HRIG) 20 IU/kg body weight given once on day 0 4
• Rabies vaccine series: 4 doses on days 0,3,7, and 14 (the updated CDC schedule as of 2009) 5
• Administration is a medical urgency, not a medical emergency, but decisions must not be delayed 1
• PEP should be administered regardless of delay length, provided the child shows no clinical signs of rabies 1

Additional Considerations

Tetanus Prophylaxis:

• Assess the child's tetanus immunization status and administer tetanus prophylaxis as indicated 2
• At 21 months, the child should have received at least 3 doses of DTaP; verify vaccination history 2

Risk Factors That Increase Rabies Suspicion:

• Unprovoked attacks are more likely to indicate rabies than provoked attacks 1, 2
• More cats than dogs are reported rabid in the United States, with the majority associated with raccoon rabies epizootics in the eastern US 2
• The average incubation period in cats is 2 months but may vary from 2 weeks to several months or even years 3

Critical Pitfalls to Avoid

• Never delay wound cleansing, as thorough wound cleansing alone has been shown to markedly reduce rabies likelihood in animal studies 2
• Do not initiate unnecessary post-exposure prophylaxis for healthy domestic cats that can be observed for 10 days 2
• Do not exceed the recommended HRIG dose, as excess can suppress active antibody production 2
• Do not administer rabies vaccine to the cat during the 10-day observation period 1

Monitoring During Observation Period

• Any illness in the cat during confinement should be evaluated by a veterinarian and reported immediately to the local public health department 1
• If signs suggestive of rabies develop during observation, immediately initiate post-exposure prophylaxis for the child 1
• The cat should be euthanized if rabies is suspected, with the head removed and shipped under refrigeration for laboratory examination 1