To the Editor.
—Serologic confirmation of antibody titer is no longer recommended following primary rabies pre-exposure and postexposure vaccination with human diploid cell vaccine, except for immunosuppressed persons.1 The foundation for this practice is the previous Centers for Disease Control experience that all persons receiving such vaccination have demonstrated an adequate antibody response (≥0.5 IU).On special request, the New York State Department of Health has continued to perform rabies serology for New York residents who have received preexposure rabies vaccination.During the period January 1,1990, through December 31, 1991, this laboratory tested serum from 201 patients vaccinated by the intradermal route. We identified 15 individuals in this group with rabies antibody titers of less than 0.5 IU in serum samples collected from 1 to 7 months following primary vaccination. All persons tested during the period who were vaccinated by the intramuscular route (N=11) and sampled within a comparable
Trimarchi CV, Safford M. Poor Response to Rabies Vaccination by the Intradermal Route. JAMA. 1992;268(7):874. doi:10.1001/jama.1992.03490070052040