Can the rabies vaccine be given as prophylaxis?

Rabies Vaccine as Prophylaxis

Yes, rabies vaccine can and should be given as pre-exposure prophylaxis to individuals at high risk for rabies exposure, including veterinarians, animal handlers, laboratory workers, rabies researchers, and certain international travelers to rabies-endemic areas. 1

Who Should Receive Pre-Exposure Prophylaxis

Pre-exposure vaccination should be offered to persons in high-risk groups including:

• Veterinarians and their staff 1
• Animal handlers and animal-control officers in areas where animal rabies is enzootic 1
• Rabies researchers and certain laboratory workers who handle rabies virus 1
• Cave explorers (spelunkers) who may encounter bats 2
• Persons who frequently handle bats, regardless of location in the United States or worldwide, due to lyssavirus presence on all continents except Antarctica 1
• International travelers likely to come in contact with animals in areas where dog or other animal rabies is enzootic and immediate access to appropriate medical care (including rabies vaccine and immune globulin) might be limited 1

Routine pre-exposure prophylaxis for the general U.S. population or routine travelers to areas where rabies is not enzootic is NOT recommended. 1

Why Pre-Exposure Prophylaxis is Given

Pre-exposure prophylaxis serves several critical purposes:

• Provides protection against unrecognized or inapparent exposures to rabies 1, 3
• Offers partial immunity to persons whose postexposure prophylaxis might be delayed, particularly important in areas where modern immunizing products might not be available 1
• Simplifies postexposure management by eliminating the need for rabies immune globulin (RIG) and decreasing the number of vaccine doses needed from 5 doses to just 2 doses 1
• Reduces risk and cost by establishing an immunologic barrier in advance and creating memory immune response 3

Primary Pre-Exposure Vaccination Regimen

Three 1.0-mL injections of HDCV or PCECV should be administered intramuscularly in the deltoid area on days 0,7, and 21 or 28. 1

Common pitfall to avoid: Never administer rabies vaccine in the gluteal area, as this results in lower neutralizing antibody titers and has been associated with prophylaxis failures. 4

Booster Dose Requirements Based on Risk Category

The need for routine booster doses depends on the level of ongoing risk:

Continuous Risk Category (Highest Risk)

• Laboratory workers handling rabies virus in research or vaccine production facilities 1
• Should have serum tested for rabies virus neutralizing antibody every 6 months 1
• Booster dose administered if titer falls below complete neutralization at 1:5 serum dilution by RFFIT 1

Frequent Risk Category

• Diagnostic laboratory workers, cavers, veterinarians and staff, animal-control and wildlife officers in rabies-enzootic areas 1
• Persons who frequently handle bats anywhere 1
• Should have serum tested every 2 years 1
• Single booster dose if titer is less than complete neutralization at 1:5 serum dilution 1

Infrequent Exposure Group

• Veterinarians, veterinary students, terrestrial animal-control and wildlife officers in areas where rabies is uncommon to rare 1
• Certain at-risk international travelers who completed full pre-exposure vaccination series 1
• Do NOT require routine serologic verification or routine pre-exposure booster doses 1
• If exposed in the future, they simply require 2 doses of vaccine on days 0 and 3 (no RIG needed) 1

Evidence on Long-Term Protection

Recent research demonstrates that a single booster dose after primary vaccination confers high and long-term immune response in nearly all individuals (99.5%), with only rare low responders. 5 Additionally, 68.6% of participants maintained adequate antibody levels (≥0.5 IU/mL) for up to 10 years without requiring any booster doses. 6

Special Populations

Pregnancy

Pregnancy is NOT a contraindication to rabies vaccination for either pre-exposure or postexposure prophylaxis when there is substantial risk of exposure. 7 Pre-exposure prophylaxis may be indicated during pregnancy if there is substantial risk of exposure to rabies. 7

Immunosuppressed Patients

Patients immunosuppressed by disease or medications (including corticosteroids) should ideally postpone pre-exposure vaccinations and consider avoiding activities requiring rabies prophylaxis. 8 When postponement is not possible, immunosuppressed persons at risk should be vaccinated by the intramuscular route (never intradermal) and have antibody titers checked to ensure adequate response. 8, 9

Critical caveat: Corticosteroids and other immunosuppressive agents can interfere with the development of active immunity and potentially predispose patients to rabies. 8

Postexposure Management for Previously Vaccinated Persons

If a previously vaccinated person is exposed to rabies:

• Administer 2 intramuscular doses (1.0 mL each in deltoid) of vaccine: one immediately and one 3 days later 1
• Do NOT administer rabies immune globulin (RIG) to previously vaccinated persons, as passive antibody might inhibit the anamnestic response 1
• Local wound care remains critically important even for previously vaccinated persons 1

Key Clinical Pearls

• No postexposure prophylaxis failures have occurred in the United States since cell culture vaccines and HRIG have been routinely used 1
• Rabies is nearly 100% fatal once clinical symptoms develop, making prevention absolutely critical 2, 10
• Postexposure prophylaxis is nearly 100% effective when used in timely and accurate fashion 2
• Pre-exposure prophylaxis does NOT eliminate the need for additional medical evaluation after a rabies exposure, but it significantly simplifies management 1