Can rabies immunoglobulin (Rabies Immune Globulin) be administered to a person with a history of previous rabies vaccination who has been exposed to rabies?

Rabies Immunoglobulin Should NOT Be Given to Previously Vaccinated Persons

Rabies immune globulin (RIG) is unnecessary and should not be administered to previously vaccinated persons who have been exposed to rabies, as it may inhibit the strength and rapidity of the expected anamnestic immune response. 1

Definition of Previously Vaccinated

Previously vaccinated persons include those who have received:

• One of the ACIP-recommended pre-exposure or post-exposure prophylaxis regimens with cell-culture vaccines (HDCV, PCECV, or RVA), regardless of how long ago vaccination occurred 1, 2, 3
• Another vaccine regimen with documented adequate rabies virus-neutralizing antibody response 1

Recommended Post-Exposure Protocol for Previously Vaccinated Persons

Previously vaccinated individuals require only:

• Two doses of rabies vaccine (1.0 mL each) administered intramuscularly in the deltoid area 1, 4, 5
• First dose immediately upon exposure (day 0) 1, 3
• Second dose 3 days later (day 3) 1, 3
• No rabies immune globulin 1, 2, 3, 6, 4, 5

Rationale for Withholding RIG

The anamnestic (memory) immune response in previously vaccinated persons:

• Produces rapid antibody production following booster vaccination 3
• Occurs regardless of pre-booster antibody titer 1, 3
• Can be suppressed or delayed by RIG administration 1, 6, 7

RIG can partially suppress active antibody production, which is counterproductive in individuals with established immunologic memory 1, 4

Critical Exception: Immunocompromised Patients

Immunocompromised individuals are the major exception and should receive:

• Full 5-dose vaccine regimen (days 0,3,7,14, and 28) 2, 6
• One dose of HRIG at 20 IU/kg body weight on day 0 2, 6
• Serologic testing 7-14 days after the last dose to confirm adequate antibody response 2, 6

Immunosuppressive conditions include:

• Corticosteroid use 1
• Other immunosuppressive medications 1, 2
• HIV/AIDS 2
• Antimalarial drugs 1
• Other immunosuppressive illnesses 2

Common Pitfalls to Avoid

Do not delay treatment to check antibody titers before administering boosters to previously vaccinated persons—this is unnecessary and inappropriate, as no specific "protective" titer threshold is definitively established for post-exposure prophylaxis 3

Never administer RIG in the same syringe or at the same anatomical site as the vaccine 1, 4

Never use the gluteal area for vaccine administration, as this produces inadequate antibody responses 1, 6, 4, 5

Timing Considerations

For the rare situation where a previously unvaccinated person received vaccine without RIG:

• RIG can be administered up to and including day 7 after the first vaccine dose 1, 4
• Beyond day 7, RIG is not indicated as antibody response to cell culture vaccine is presumed to have occurred 1
• Research suggests RIG can be given up to 5 days after vaccine initiation without significant antibody suppression 8

However, this timing guidance applies only to previously unvaccinated persons, not to those with prior vaccination history who should never receive RIG 1