Rabies neutralizing antibody response to different schedules of serum and vaccine inoculations in non-exposed persons. II.

Further studies were made on groups of adult humans, previously unexposed to rabies and with no history of rabies vaccination, who were inoculated with different schedules of phenolized inactivated vaccine given subcutaneously and high egg passage (HEP) Flury strain vaccine given intradermally, with and without inoculation of antirabies serum. Serum specimens of the inoculated individuals were studied for antibody up to the 60th day after the first inoculation of the vaccines and serum. Studies were also made on the effect of "booster" doses of HEP Flury strain vaccine given 6 months after preparatory inoculations. The results can be summarized as follows:1. Fourteen daily inoculations of phenolized vaccine produced a superior antibody response to that obtained with 3 inoculations given 5 days apart.2. Three intradermal inoculations of HEP Flury vaccine given 5 days apart gave a low level of antibody response, but these individuals responded efficiently by producing antibody to a "booster" dose of the same vaccine given 6 months later.3. Administration of phenolized vaccine or of HEP Flury vaccine alone did not produce detectable antibody in most individuals until between the 10th and the 15th day after the first inoculation of the vaccine.4. Passive antibody following inoculation of antirabies serum persisted in some individuals for as long as 42 days. Two inoculations of serum administered 5 days apart did not give levels of antibody higher than those obtained with one inoculation.5. One inoculation of serum completely suppressed antibody response to 3 inoculations of Flury vaccine given intradermally 5 days apart, and also prevented the preparation of the individuals to respond to a later "booster" dose of this vaccine.6. Three inoculation of phenolized vaccine given 5 days apart acted efficiently in producing antibody by the 60th day. However, the interfering action of one and two inoculations of serum was clearly defined in this schedule.7. One inoculation of serum had no suppressive effect on the active antibody response to 14 daily doses of phenolized vaccine; two doses of serum given in the same combination definitely interfered with the production of an active antibody response.