Which vaccine(s) should be given after a stray cat scratch?

Rabies Vaccine and Immunoglobulin Are Required After a Stray Cat Scratch

For a stray cat scratch, you must administer rabies post-exposure prophylaxis (PEP) consisting of both human rabies immune globulin (HRIG) and a 4-dose rabies vaccine series, plus ensure tetanus vaccination is current.

Primary Vaccination Protocol

Rabies Post-Exposure Prophylaxis (Most Critical)

A stray cat scratch is a Category III exposure requiring immediate full rabies PEP because the animal cannot be quarantined for 10-day observation 1, 2. The protocol includes:

For Previously Unvaccinated Patients:

• HRIG: 20 IU/kg body weight administered once on day 0

  • Infiltrate the full dose around and into the wound if anatomically feasible
  • Any remaining volume given IM at a site distant from vaccine administration
  • Never administer in the same syringe or site as the first vaccine dose 1, 2

• Rabies Vaccine (HDCV or PCECV): 1.0 mL IM on days 0,3,7, and 14 1

  • Administer in the deltoid area for adults
  • Use anterolateral thigh for young children
  • Never use the gluteal area (results in lower antibody titers) 2

For Previously Vaccinated Patients:

• HRIG is NOT given
• Vaccine only: 1.0 mL IM on days 0 and 3 1

Tetanus Prophylaxis (Secondary Priority)

Cat scratches can transmit tetanus, even in previously immunized patients 3. Assess tetanus immunization status:

• If last dose >5 years ago for contaminated wounds: give tetanus booster
• If last dose >10 years ago for clean wounds: give tetanus booster
• If incomplete primary series: complete the series 2, 4

Critical Wound Management

Immediate wound care is essential and can markedly reduce rabies transmission risk 2:

• Thoroughly cleanse all wounds with soap and water immediately
• Irrigate with povidone-iodine solution if available
• Avoid suturing when possible (delays increase infection risk)
• Do not damage surrounding tissue during cleaning 1, 2

Common Pitfalls to Avoid

1. Delaying rabies PEP while attempting to locate the cat: Assume a stray cat is rabid if it cannot be quarantined for 10 days. Do not delay treatment 5

2. Administering HRIG after day 7: HRIG can only be given up to day 7 of the vaccine series; beyond this, antibody response to vaccine is presumed to have occurred 2

3. Giving inadequate HRIG at wound site: Failures have occurred when less than the full amount was infiltrated around the wound 2

4. Using the gluteal area for vaccine: This results in lower neutralizing antibody titers and has been associated with prophylaxis failures 2

5. Assuming minor scratches don't require PEP: Cat scratches constitute significant rabies exposure, particularly from stray animals. Even a case of paralytic rabies following cat scratch has been documented 6

Additional Considerations

While cat-scratch disease (Bartonella henselae) and other infections like Pasteurella multocida are concerns with cat scratches 4, 7, rabies prevention takes absolute priority due to its 100% fatality rate once symptoms develop. The rabies PEP protocol has demonstrated no failures in the United States since modern cell culture vaccines and HRIG have been routinely used 2.

Immunocompromised patients require a 5-dose vaccine schedule (days 0,3,7,14, and 28) instead of the standard 4-dose regimen 1.