Improvement of the antigenicity of antirabies vaccine by pooling checked by post-challenge vaccination of guinea-pigs.

The author describes some studies carried out at the Pasteur Institute of Southern India, Coonoor, with the object of developing an antirabies vaccine of uniform potency.It was found that by pooling batches of vaccine from several infected sheep brains a vaccine was produced which was superior in antigenicity (as determined by potency tests in mice) to the NIH (United States National Institutes of Health) Reference Vaccine 155-D as well as to most of the individual batches of vaccine tested. Furthermore, the pooled vaccine conferred a significant degree of protection on guinea-pigs challenged with virulent strains of street virus, even when not administered until an hour after infection.A brief outline is given of the method used for pooling the vaccine.