Preliminary observations in primary antirabies immunization of man with different types of high-egg-passage Flury virus.

High-egg-passage (HEP) Flury rabies vaccines, with a suckling-mouse LD(50) titre of 10(6.0) or more per ml, were used for primary immunization of 149 individuals showing no rabies antibodies in their pre-vaccination sera. An antibody response was elicited in 142, or 95%, of the total. A centrifuged vaccine reduced side reactions to a minimum. This same vaccine induced an antibody response in all of 79 individuals vaccinated. Furthermore, the antibody titre in this latter group approached that obtained with three injections of Semple-type vaccine.