Intradermal use of human diploid cell vaccine for preexposure rabies immunizations.

In a study involving 240 faculty, students, and staff at the University of Georgia College of Veterinary Medicine, 0.1 ml of a rabies human diploid cell vaccine administered intradermally on days 0, 7, and 28 induced adequate rabies antibody (greater than or equal to 0.5 IU/ml of serum) in all subjects by day 49. There were no significant differences in mean titers between groups of individuals with different rabies immunization histories by using a newly proposed index system for reporting such titers. It was shown that if there was a titer on the day the initial dose was given, it had no bearing on the titer 49 days later. Less than 1% of all the injections resulted in severe reactions, ie, muscular pain, headache, or pain at the site of injection. It was concluded that intradermal use of a low dose of rabies human diploid cell vaccine will induce adequate antibody titers in persons at risk to rabies.