Do patients receiving the rabies vaccine series require Rabies Immune Globulin (RIG) in addition to the vaccine?

From the Guidelines

For patients receiving the rabies vaccine series, the need for rabies immune globulin (RIG) depends on their exposure status, and for post-exposure prophylaxis (PEP) after a potential rabies exposure, patients should receive both rabies immune globulin and the vaccine series. The RIG is given only once at the beginning of treatment, with as much as possible infiltrated around the wound site and any remaining volume administered intramuscularly at a site distant from the vaccine 1. The standard vaccine series consists of four doses given on days 0,3,7, and 14, as recommended by the Advisory Committee on Immunization Practices (ACIP) 1. For pre-exposure prophylaxis (for those at high risk of exposure), only the vaccine is given without immune globulin, typically as a series on days 0,7, and 21 or 28 1. RIG provides immediate passive immunity while the vaccine stimulates the body's own immune response, which takes approximately 7-10 days to develop 1. This combination approach for post-exposure cases maximizes protection during the critical window before vaccine-induced immunity develops fully. Key considerations include:

• The dose of HRIG should not exceed the recommended dose to avoid suppressing active production of antibodies 1.
• HRIG should be administered once, at the beginning of antirabies prophylaxis, to previously unvaccinated persons 1.
• For persons who have ever previously received complete vaccination regimens with a cell culture vaccine, or who have been vaccinated with other types of vaccines and have previously had a documented rabies virus neutralizing antibody titer, only vaccine is needed for postexposure prophylaxis 1.

From the FDA Drug Label

The essential components of rabies post-exposure prophylaxis are wound treatment and, for previously unvaccinated persons, the administration of both human rabies immune globulin (RIG) and vaccine. Administer post-exposure antirabies vaccination with rabies vaccine in addition to administering Rabies Immune Globulin (RIG) However, for persons who have previously received complete vaccination regimens (pre-exposure or post-exposure) with a cell culture vaccine or persons who have been vaccinated with other types of vaccines and have had documented rabies antibody titers, administer the vaccine alone

Patients receiving the rabies vaccine series should receive both the vaccine and Rabies Immune Globulin (RIG), unless they have previously received complete vaccination regimens, in which case they should receive the vaccine alone 2.

• Key points:
  • Previously unvaccinated persons should receive both RIG and vaccine
  • Previously vaccinated persons with documented rabies antibody titers should receive vaccine alone
  • The combination of RIG and vaccine is recommended for both bite exposures and nonbite exposures 2
  • Consult local and state public health officials if questions arise about the need for rabies prophylaxis 2

From the Research

Rabies Vaccine Series and Immune Globulin Administration

• Patients receiving the rabies vaccine series typically require both the vaccine and immune globulin for post-exposure prophylaxis, as the immune globulin provides immediate protection until the vaccine takes effect 3, 4, 5.
• The administration of immune globulin is generally recommended in conjunction with the first dose of the rabies vaccine, with the dose calculated according to body weight 3, 6, 5.
• The immune globulin can be administered intramuscularly (i.m.) or intravenously (i.v.), with i.v. administration showing higher serum neutralizing antibody concentrations and potential economic advantages 3.
• Local wound management, including infiltration of the wound with immune globulin, is an essential part of post-exposure rabies prophylaxis, although adherence to this recommendation may vary 4, 6.

Patient Selection and Dosing

• The decision to administer immune globulin is based on the patient's exposure category and medical history, with guidelines recommending its use for category III animal exposures and for patients who have not previously received rabies vaccination 6, 5.
• The dose of immune globulin is typically 20 IU/kg of body weight, administered as soon as possible after exposure, with 98% of patients in one study receiving doses within 10% of this recommended dose 3, 6.
• The timing of immune globulin administration is critical, with guidelines recommending its use within 7 days of the first rabies vaccine administration, and ideally as soon as possible after exposure 6, 5.

Safety and Efficacy

• The safety and efficacy of human rabies immunoglobulin have been demonstrated in several studies, with minimal adverse events reported and high rates of patient survival and recovery 4, 6.
• The use of immune globulin in conjunction with rabies vaccine has been shown to be highly effective in preventing rabies, with studies demonstrating 100% protection in patients receiving both treatments 3, 4.