Use of a Reduced (4-Dose) Vaccine Schedule for Post-exposure Prophylaxis to Prevent Human Rabies
To: Vermont Health Care Providers
From: Robert Johnson, State Public Health Veterinarian
Date: March 29, 2010
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The Advisory Committee on Immunization Practices (ACIP) has revised the recommendations for postexposure prophylaxis (PEP) to prevent human rabies from a five-dose rabies vaccination regimen to a four-dose regimen for immunocompetent people.
Previously, ACIP recommended a five-dose rabies vaccination regimen with human diploid cell vaccine (HDCV) or purified chick embryo cell vaccine (PCECV). The new recommendations reduce the number of vaccine doses to four. The reduction in doses recommended for PEP was based in part on evidence from rabies virus pathogenesis data, experimental animal work, clinical studies, and epidemiologic surveillance.
These studies indicated that four vaccine doses in combination with rabies immune globulin (RIG) elicited adequate immune responses, and that a fifth dose of vaccine did not contribute to more favorable outcomes.
New ACIP Recommendations
- For people previously unvaccinated with rabies vaccine:
A combination of RIG and vaccine is recommended for both bite and non-bite exposures, regardless of time between exposure and initiation. However, PEP should start as soon as possible after the exposure.
RIG is administered once on day 0, at the time PEP is begun. If anatomically feasible, the full dose of RIG is infiltrated around and into any wounds. Any remaining volume is injected intramuscularly at a site distant from vaccine administration.
Four 1-mL doses of HDCV or PCECV are administered intramuscularly on days 0, 3, 7 and 14. Day 0 is the first day the vaccine is given.
The recommendations have not changed for people with immunosuppression.
Rabies vaccine is administered using a five-dose regimen, with doses given on day 0, 3, 7, 14, and 28. RIG is given as above.
- For people previously vaccinated with rabies vaccine:
Recommendations have not changed, with two doses of rabies vaccine administered on days 0 and 3 using HDCV or PCECV. RIG is not used.
- Pre-exposure prophylaxis:
Recommendations for pre-exposure prophylaxis also remain unchanged, with three doses of vaccine administered on days 0, 7, and 21 or 28.
Note: These new ACIP recommendations differ from current rabies vaccine label instructions, which still list the five-dose series for PEP. Alterations of current product labels for HDCV and PCEC are not anticipated by the producers of human rabies vaccines licensed in the United States.
To read this more about this recommendation, see MMWR RR-2, March 19, 2010 / 59(02);1-9: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5902a1.htm
For more information about rabies, see the Vermont Depart of Health’s website: http://healthvermont.gov/prevent/rabies/Rabies.aspx