Should a previously rabies-vaccinated patient receive rabies immunoglobulin after a new bite?

No, Previously Vaccinated Patients Do NOT Need Rabies Immunoglobulin

If the patient was previously vaccinated against rabies, you should NOT give rabies immunoglobulin (HRIG) this time—only administer 2 doses of rabies vaccine on days 0 and 3. 1, 2

The Core Principle

The CDC and ACIP are unequivocal: previously vaccinated persons require only a simplified 2-dose vaccine booster and HRIG is contraindicated because it can actually inhibit the anamnestic (memory) antibody response that their immune system will mount rapidly. 2

Who Qualifies as "Previously Vaccinated"

A patient is considered previously vaccinated if they received ANY of the following: 1

• Any complete ACIP-recommended pre-exposure prophylaxis regimen with cell-culture vaccines
• Any complete post-exposure prophylaxis regimen with cell-culture vaccines (HDCV, PCECV, or RVA)
• This applies regardless of how long ago the vaccination occurred—even if it was many years prior 1

Research confirms that neutralizing antibodies remain detectable 5-21 years after initial vaccination, and all previously vaccinated individuals mount an accelerated antibody response after just two booster doses. 3

The Correct Regimen for Previously Vaccinated Patients

Administer only: 1, 2

• 1.0 mL vaccine intramuscularly in the deltoid on day 0
• 1.0 mL vaccine intramuscularly in the deltoid on day 3
• NO rabies immunoglobulin at all

The Critical Exception: Immunocompromised Patients

Immunocompromised patients are the ONE exception where you DO give HRIG even if previously vaccinated. 1, 2

For immunocompromised patients, provide: 1, 2

• HRIG at 20 IU/kg body weight on day 0
• Extended 5-dose vaccine schedule (days 0,3,7,14, and 28)
• Serologic testing to confirm adequate antibody response

Immunosuppressive conditions include: 1

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

Why HRIG is Harmful in Previously Vaccinated Patients

The immunologic memory from prior vaccination allows previously vaccinated patients to mount a rapid anamnestic response within days. Giving HRIG in this situation suppresses this memory response and is counterproductive. 2 The passive antibodies from HRIG are unnecessary because the patient's immune system will quickly produce its own antibodies from the booster doses. 1

Timing Considerations

If HRIG was mistakenly not given to an unvaccinated patient initially, it can still be administered up to and including day 7 of the vaccine series. 2, 4 However, beyond day 7, HRIG is not indicated because vaccine-induced antibodies are presumed to have developed. 2

No Routine Serologic Testing Needed

For healthy, immunocompetent previously vaccinated persons, routine serologic testing after the 2-dose booster is unnecessary because the immune system will reliably mount an adequate response based on immunologic memory. 1 Testing is only indicated for immunocompromised patients. 4

Administration Details

• Always inject in the deltoid muscle for adults (or anterolateral thigh for young children) 1
• Never inject in the gluteal area—this produces inadequate antibody responses and is associated with vaccine failure 4
• Initiate PEP as soon as possible after exposure, though treatment remains indicated regardless of time elapsed 1