The efficacy of a cultured rabies vaccine studied on guinea pigs previously infected with the rabies street virus

In this work materials on the development of an experimental model for the study of rabies vaccines are presented. The comparative study of different immunization schedules for vaccines with different protective potency has been carried out. Guinea pigs infected with street rabies virus, strain k, were used as an experimental model. As shown in this investigation the optimum method of infecting the animals with strain k was intramuscular injection causing 50% mortality among the animals, the incubation period lasting 10-24 days. Only those tissue-culture rabies vaccines which had activity equal to 1.0-1.3 I. U. and, when injected into the animals, ensured survival rate ranging from 57% to 76%, depending on the immunization schedule, were shown to possess protective potency. It should be pointed out that survival rate among the animals receiving the preparation according to the reduced schedules recommended by WHO was higher than among those immunized daily for 14 days. In all groups immune response was observed. Still in the animals receiving the preparation according to the reduced schedules a higher level of virus-neutralizing antibodies was registered. Thus, an experimental model capable of being used for the evaluation of the quality of existing and newly developed antirabies preparations was obtained. Besides, we believe it to be expedient to carry out the field trial of rabies vaccines with activity equal to 1.0-1.3 I. U., using the reduced immunization schedules.