What is the recommended post‑exposure rabies vaccination schedule (days of dosing) for an unvaccinated adult, including rabies‑immune globulin administration and any adjustments for immunocompetent versus immunocompromised patients or those with prior pre‑exposure vaccination?

Rabies Post-Exposure Prophylaxis Vaccination Schedule

For previously unvaccinated immunocompetent adults, administer 4 doses of rabies vaccine (HDCV or PCECV) intramuscularly on days 0,3,7, and 14, combined with rabies immune globulin (HRIG) 20 IU/kg infiltrated into and around the wound on day 0. 1, 2, 3

Standard Regimen for Unvaccinated Immunocompetent Patients

Vaccine Schedule

• Administer 1.0 mL of HDCV or PCECV intramuscularly on days 0,3,7, and 14 (day 0 is the day the first dose is given, not the day of exposure). 1, 3
• Inject into the deltoid muscle for adults and older children; the anterolateral thigh is acceptable for infants and young children. 1, 3
• Never administer vaccine in the gluteal area, as this results in inadequate immune response and vaccine failure. 1, 3, 4

Rabies Immune Globulin (HRIG)

• Give HRIG once only on day 0 at a dose of 20 IU/kg body weight. 1, 2, 3
• Infiltrate as much HRIG as anatomically feasible around and into the wound(s); inject any remaining volume intramuscularly at a site distant from the vaccine injection site. 1, 2
• If HRIG was not given on day 0, it can still be administered up to and including day 7 of the vaccine series; beyond day 7, HRIG should not be given because vaccine-induced antibodies are presumed to have developed. 1, 3
• Never administer HRIG in the same syringe or at the same anatomical site as the vaccine, as this can interfere with vaccine efficacy. 1, 3
• Never exceed the 20 IU/kg dose, as higher doses suppress active antibody production. 1, 2, 3

Essential Wound Care

• Immediately wash all wounds thoroughly with soap and water for 15 minutes before any other intervention—this is the single most effective measure for preventing rabies. 5, 2, 3
• Irrigate wounds with a virucidal agent such as povidone-iodine solution if available. 5, 2

Modified Regimens for Special Populations

Previously Vaccinated Persons

• Administer only 2 doses of vaccine (1.0 mL each) on days 0 and 3. 1, 2, 3
• Do NOT give HRIG to previously vaccinated persons, as it will suppress the anamnestic immune response. 1, 2, 3
• "Previously vaccinated" means completion of a full pre-exposure or post-exposure prophylaxis series with cell-culture vaccine, or documented adequate rabies virus-neutralizing antibody response. 1

Immunocompromised Patients

• Administer a 5-dose vaccine regimen on days 0,3,7,14, and 28 plus HRIG 20 IU/kg on day 0. 1, 5, 2, 3
• Perform serologic testing 7-14 days after the final dose to confirm adequate antibody response (≥0.5 IU/mL by RFFIT). 5, 3
• This 5-dose regimen applies even to immunocompromised patients who were previously vaccinated. 3

Schedule Adherence and Missed Doses

Timing Flexibility

• Initiate post-exposure prophylaxis as soon as possible after exposure, ideally within 24 hours, though there is no absolute cutoff beyond which treatment should be withheld. 2
• Delays of a few days for individual doses are unimportant and do not compromise protection. 1, 3
• If a dose is missed, administer it immediately when the patient presents and resume the schedule maintaining the same intervals between doses. 1, 3
• For example, if the day 7 dose is missed and the patient presents on day 10, give that dose on day 10 and administer the remaining dose on day 17 (maintaining the 7-day interval). 1

When Serologic Testing Is Indicated

• Routine post-vaccination antibody testing is not necessary for healthy immunocompetent patients completing the 4-dose regimen, as 100% demonstrate adequate antibody response. 1, 3
• Consider serologic testing when substantial deviations from the schedule occur, for immunocompromised patients, or when there are concerns about vaccine potency or administration technique. 1, 3

Critical Pitfalls to Avoid

• Never use the gluteal area for vaccine administration—this is associated with vaccine failure. 1, 3, 4
• Never exceed 20 IU/kg of HRIG—higher doses suppress active antibody production. 1, 2, 3
• Never give HRIG and vaccine in the same syringe or anatomical site. 1, 3
• Never give HRIG to previously vaccinated immunocompetent persons—this critically impairs the memory immune response. 1, 2, 3
• Do not delay wound cleaning—it is the most crucial first step. 5, 2, 3

Efficacy

• When administered promptly and appropriately, this post-exposure prophylaxis regimen combining wound care, HRIG infiltration, and the vaccine series is nearly 100% effective in preventing human rabies. 2
• The 4-dose regimen produces adequate antibody response in all healthy persons, with 100% seroprotection maintained through day 180. 3