Evaluation of the ERA antirabies vaccine against antigenic variants of rabies virus in different post-immunization periods

Abstract

Protection levels of an attenuated antirabies vaccine, of ERA origin, prepared in Kidney tissue culture, were evaluated in mice. Two schemes of vaccination were utilized: a single dose and 6 doses on alternate days. Animals of different experimental groups were challenged at 15, 30, 60 and 120 days post-immunization with six antigenic variants of rabies virus: strains of dog origin (S. Paulo, Brazil and Nigéria), vampire origin (DR-19 and Pernambuco, Brazil), fox origin (Rio Grande do Norte,Brazil), and CVS (Challenge Virus Standard). The results showed the effectiveness of the ERA vaccine against all antigenic variants of street and sylvatic rabies virus, independently of the vaccination scheme. Against the laboratory strains (DR-19 and CVS) the ERA vaccine was less effective, mainly in the groups vaccinated with a single dose.