The present invention relates to assays for the identification of compounds that inhibit assembly of NP, VP35, and VP24, or inhibit the glycosylation of NP, required for nucleocapsid formation, for use as anti-viral agents. The invention also relates to assays for the identification of compounds that block glycosylation of proteins having a glycosylation domain that is substantially homologous to a glycosylation domain of NP required for polymerization. The invention further relates to pseudoparticles for presentation of antigens or antigenic epitopes for immunogenic or vaccination purposes.