Fil: Cisterna, Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirus; Argentina.Fil: Bonaventura, Romina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirus; Argentina.Fil: Caillou, Susana. División de zoonosis; Tucuman, Argentina.Fil: Pozo, Oscar. Ministerio de Salud. División de Zoonosis Urbana; Argentina.Fil: Andreau, Maria Lidia. Laboratorio Regional de Diagnóstico de Rabia; Chaco, Argentina.Fil: Dalla Fontana, María L. Laboratorio de Zoonosis; Santa Fe, Argentina.Fil: Echegoyen, Cristina. Dirección Nacional de Epidemiología; Argentina.Fil: de Mattos, Carlos. Centers for Desease Control and Prevention. Rabies Section; Estados Unidos.Fil: de Mattos, Cecilia. Centers for Desease Control and Prevention. Rabies Section; Estados Unidos.Fil: Russo, Susana. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorios y Control Técnico; Argentina.Fil: Novaro, Laura. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorios y Control Técnico; Argentina.Fil: Elberger, Diana. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorios y Control Técnico; Argentina.Fil: Freire, María Cecilia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirus; Argentina.The nucleoprotein genes of 54 human, domestic and wild animals rabies isolates obtained in Argentina between 1995 and 2002 were characterized using monoclonal antibodies and partial gene sequence analysis. The antigenic and genetic diversities of rabies virus in samples from bat and bat-related cases were studied, leading to the identification of five distinct genetic variants. Rabies viruses isolated from vampire bat related cases were very similar to each other, showing 98.9% overall similarity. Specific antigenic variants (AgV) were detected associated with different insectivorous bats species, in samples from Tadarida brasiliensis and Eumops patagonicus bats. In contrast, isolates from Myotis sp. and Histiotus sp. bats could not be matched to any antigenic type. Additionally, bat rabies cases were also detected in southern provinces previously considered rabies-free. Finally, two independent antigenic and genetic variants co-circulating in northern Argentina were found in isolates obtained from dogs and dog-related cases, suggesting two independent cycles of virus transmission. This is the first national coordinated study of antigenic as well as molecular epidemiology of rabies in Argentina. The information presented here will improve our knowledge about rabies epidemiology and therefore, will assist preventing fatal human cases.