What is the recommended prophylaxis for rabies exposure?

Rabies Post-Exposure Prophylaxis

For previously unvaccinated individuals with Category III exposure (bites, scratches with bleeding, or mucous membrane contamination), immediately administer thorough wound washing, Human Rabies Immune Globulin (HRIG) 20 IU/kg infiltrated around the wound, and initiate a 5-dose rabies vaccine series on days 0,3,7,14, and 28. 1, 2

Exposure Risk Categorization

The WHO categorizes rabies exposures into three distinct categories that determine prophylaxis requirements 1:

Category I (No Prophylaxis Needed):

• Touching or feeding animals, contact with intact skin, or licks on intact skin 1
• These exposures do not constitute true rabies risk 2

Category II (Vaccine Only):

• Nibbling of uncovered skin without bleeding, minor scratches without bleeding, or licks on broken skin 1
• Requires 15 minutes of thorough wound washing with soap and water plus vaccine series, but no immunoglobulin 1

Category III (Full Prophylaxis Required):

• Any penetration of skin by teeth (bite), contamination of mucous membranes with saliva, or contamination of open wounds with saliva 1, 2
• Requires immediate wound washing, HRIG, and complete vaccine series 1

Post-Exposure Prophylaxis Protocol

For Previously Unvaccinated Persons

Immediate wound management is critical and can markedly reduce rabies likelihood 1:

• Wash all wounds thoroughly for 15 minutes with soap and copious amounts of water 1, 2
• Apply iodine-containing or viricidal topical preparation where available 2

HRIG administration:

• Dose: 20 IU/kg body weight 1, 2
• Infiltrate as much as possible around the wound site, with any remaining volume given intramuscularly at a site distant from vaccine administration 1

Vaccine schedule:

• 5 doses of HDCV or PCECV, 1.0 mL per dose 1
• Given on days 0,3,7,14, and 28 1, 2
• Administer intramuscularly in the deltoid area only (never gluteal area in adults and older children) 1

For Previously Vaccinated Persons

Simplified regimen with no immunoglobulin required 1, 2:

• Only 2 doses of vaccine (1.0 mL each) needed 1
• Given on days 0 and 3 1, 2
• HRIG should not be administered to previously vaccinated persons as it may interfere with the anamnestic response 1

Animal-Specific Risk Assessment

High-risk animals requiring immediate prophylaxis unless proven negative 1, 3, 2:

• Bats, skunks, raccoons, foxes, coyotes, and bobcats 1, 3
• These should be regarded as rabid unless laboratory testing proves otherwise 2

Low-risk animals (prophylaxis almost never required) 3, 2:

• Small rodents (rats, mice, squirrels, hamsters, guinea pigs, gerbils, chipmunks) 3, 2
• Lagomorphs (rabbits and hares) 3, 2
• These species do not serve as rabies reservoirs and transmission to humans has not been documented in the United States 3

Domestic animals (dogs, cats, ferrets) 2:

• If healthy and available for 10-day observation, delay prophylaxis unless animal develops clinical signs 2
• If rabid or suspected rabid, begin prophylaxis immediately 2

Pre-Exposure Prophylaxis

High-risk groups requiring pre-exposure vaccination 1:

• Veterinarians and staff, animal handlers, rabies researchers, laboratory workers 1
• Cave explorers and diagnosticians 4

Pre-exposure protocol:

• 3 doses of HDCV or PCECV (1.0 mL each) 1, 5
• Given intramuscularly in deltoid on days 0,7, and 21 or 28 1, 5
• Booster doses: every 6 months for continuous risk category, every 2 years for frequent risk category 1

Advantage of pre-exposure prophylaxis:

• Simplifies post-exposure treatment by eliminating need for HRIG 6
• Particularly important for travelers to rabies-endemic areas where HRIG may be unavailable 6

Critical Pitfalls to Avoid

Common errors that can be fatal 1:

• Delaying post-exposure prophylaxis, especially with severe wounds to face and head 1
• Failure to recognize bat bites, which may be minor and undetected 1
• Administering vaccine in gluteal area instead of deltoid 1
• Giving HRIG to previously vaccinated persons 1

Remember: Once clinical rabies develops, death is nearly inevitable—postexposure prophylaxis is nearly 100% effective when used promptly and correctly 4.