The neutralizing antibody patterns evoked for selected Group B arthropod-borne viruses in response to inoculation with the living attenuated 17D yellow fever vaccine were compared in two groups of human subjects with the following characteristics: (1) subjects with no evidence of previous Group B arbor virus infection, and (2) subjects who had experienced primarily natural Japanese encephalitis virus infection some time prior to vaccination. The previous experience with the JE virus did not alter the pattern of appearance of YF neutralizing antibodies, either in time of appearance or in height of antibody titer. Nor did the administration of the related YF virus significantly alter the level of JE neutralizing antibodies. However, subjects with prevaccination JE antibodies developed antibodies that neutralized chiefly dengue type 1 and West Nile viruses in response to the 17D strain inoculation while subjects without prevaccination Group B arbor virus antibodies did not.
Present address: Merck Institute for Research, West Point, Pennsylvania.