On Mar. 19, 2010, the Immunization Practices Advisory Committee (ACIP) recommended use of a reduced (4-dose) vaccine schedule for PEP to prevent human rabies.

Previously, ACIP recommended a 5-dose rabies vaccination regimen with human diploid cell vaccine (HDCV) or purified chick embryo cell vaccine (PCECV).  Studies indicated that 4 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.