RESUMO
Rinderpest is an acute and highly contagious viral disease of ruminants, often resulting in greater than 90% mortality. We previously reported the development of first- and second-generation recombinant vaccinia virus vaccines which provide complete protection against rinderpest virus (RPV) and peste-des-petits ruminants virus (PPRV). These vaccines are safe even for immunodeficient mice and macaques with acquired immunodeficiency syndrome. We developed a third-generation recombinant vaccinia virus vaccine (v2RVFH) that expresses the fusion and haemagglutinin genes of RPV under strong synthetic vaccinia virus promoters. Cattle vaccinated intramuscularly with as little as 10(3) plaque-forming units (PFU) of v2RVFH were completely protected from rinderpest. Vaccinated animals did not develop pock lesions or transmit v2RVFH to contact animals. Cattle vaccinated with a standard dose of 10(8) PFU of v2RVFH developed long-term, sterilizing immunity against rinderpest. Thus, v2RVFH is safe, efficacious, heat stable, inexpensive, easily administered, and allows serological differentiation between vaccinated and infected animals. To aid in diagnosis and differentiation of vaccinated from infected animals, we developed indirect ELISAs (iELISAs) that use baculovirus-expressed RPV or PPRV nucleoprotein as coating antigens. A single larva contains enough viral antigen to test more than 10,000 serum samples, in duplicate. African scientists trained at the ILMB successfully transferred the iELISA kit technology to more than 30 countries in Africa, providing a model for technology transfer among developing countries. Vaccination with v2RVFH, in conjunction with the iELISA kits, greatly enhances the prospects for global eradication of rinderpest, as developing nations achieve independence in control efforts.