A model in mice for the study of the early death phenomenon after vaccination and challenge with rabies virus.

The reactions of mice were studied for a period of 10 days after their vaccination with an inactivated rabies vaccine. The kinetics of their resistance to an intracerebral challenge and neutralizing antibody activity of their serum were determined daily. Protection began on the fourth day after vaccination and was approximately correlated with virus-neutralizing antibody titres from the sixth to the tenth day. However, in vaccinated mice still unprotected, death following the intracerebral challenge occurred earlier than in unvaccinated control mice. This "early death phenomenon" is proposed as a model for immuno-pathological study of reaction to rabies vaccines.