Rabies Post-exposure Prophylaxis

Rabies Post-exposure Prophylaxis (PEP)

The Advisory Committee on Immunization Practices (ACIP) develops the U.S. recommendations about how to use vaccines to prevent disease in the United States, including how to prevent rabies in people.

Rabies PEP consists of wound washing, a dose of human rabies immune globulin (HRIG) and rabies vaccine given at the time of your first medical visit, and a dose of vaccine given again on days 3, 7, and 14 after the first dose. Pregnancy is not a contraindication for rabies PEP, and exposure to rabies or a rabies diagnosis in the mother does not require pregnancy termination.

Wound care

Regardless of the risk for rabies, bite wounds can cause serious injury, such as nerve or tendon laceration and infection. For many types of bite wounds, immediate and gentle irrigation with water or a dilute water povidone-iodine solution has been shown to markedly decrease the risk of bacterial infection.

Wound cleansing is especially important in rabies prevention since, in animal studies, thorough wound cleansing alone without other medical treatments (e.g., PEP) has been shown to markedly reduce the likelihood of rabies.

Decisions regarding the use of antibiotics and primary wound closure should be made together with the patient.

Rabies vaccine

For people who have never been vaccinated against rabies, PEP should always include the administration of both HRIG and rabies vaccine. The combination of HRIG and vaccine is recommended for both bite and non-bite exposures, regardless of the interval between exposure and initiation of treatment, so long as the patient is not showing signs consistent with rabies.

People who have been previously vaccinated or are receiving pre-exposure vaccination for rabies should not receive HRIG. PEP for persons who have previously been vaccinated against rabies consists of two doses of vaccine, 3 days apart.

The vaccine should be given at recommended intervals for best results. Minor deviations of just several days are acceptable, but longer deviations in this schedule may reduce PEP effectiveness. Talk to your local or state public health officials if the patient will not be able to receive their vaccination at the recommended interval. Vaccines should never be administered into the gluteal area.

Human Rabies Immune Globulin

HRIG is administered only once at the beginning of the PEP course, and only to previously unvaccinated persons. This will provide immediate antibodies until the body can respond to the vaccine by actively producing antibodies of its own. The recommended dose of HRIG is 20 IU/kg body weight. This formula applies to all age groups, including children. Certain HRIG products are highly concentrated; practice caution when determining the correct volume of HRIG for a patient.

If possible, the full dose of HRIG should be thoroughly infiltrated into the area around and into the wounds. Any remaining volume should be injected intramuscularly at a site distant from vaccine administration. Because HRIG can partially suppress the active production of antibodies, no more than the recommended dose should be administered.

HRIG should never be administered in the same syringe or in the same anatomical site as the first vaccine dose. However, subsequent doses of vaccine in the four-dose series can be administered in the same anatomic location where the HRIG dose was administered.

If HRIG was not administered when vaccination was begun, it can be administered up to the third dose of vaccine (Day 7). After the third dose is administered, HRIG is not recommended since an antibody response to the vaccine is presumed to have occurred.

Post-exposure prophylaxis for non-immunized Individuals

Post-exposure prophylaxis for previously immunized individuals

Medical care received outside of the U.S.

Rabies PEP received outside the U.S. may include medications not used in the United States. When returning to the United States, additional therapy might be necessary. Public health officials [link] should be contacted for specific advice in such cases.

Generally, if the PEP regimen received is recognized by the World Health Organization (WHO) [Link to TRS], then no further medical care is necessary. If the regimen is not recognized by WHO, or if the PEP regimen was not completed outside of the United States, then additional doses and confirmation of an adequate vaccine response may be necessary. If titers are obtained, specimens collected 2-4 weeks after preexposure or postexposure prophylaxis would be considered adequate if the titer meets or exceeds 0.5 international units per milliliter [Link to diagnostics page].

Purified equine rabies immune globulin (ERIG) has been used effectively in developing countries where HRIG might not have been available. The occurrence of adverse reactions has been low, and most of reactions that occurred were minor. In addition, unpurified anti-rabies serum might still be used in some countries where neither HRIG nor ERIG are available. The use of this anti-rabies serum is associated with higher rates of serious adverse reactions, including anaphylaxis. Monoclonal antibodies have been proposed as an alternative to rabies immune globulin. Use of this product is only advised, if it is licensed in the country where it was administered.

Although no PEP failures have occurred in the United States since cell culture vaccines have been routinely used, failures have occurred abroad when some deviation was made from the recommended PEP protocol or when less than the currently recommended amount of rabies immune globulin (RIG) was administered. Specifically, patients who contracted rabies after PEP did not have their wounds cleansed with soap and water, received rabies vaccines in the gluteal area, and/or did not receive RIG around the wound site.

For more information about PEP, also see the international WHO guidelines for rabies postexposure treatment.