Synthetic peptide vaccine against Taenia solium pig cysticercosis: successful vaccination in a controlled field trial in rural Mexico

Taenia solium cysticercosis seriously affects human health when localised i n the central nervous system (CNS) and causes great economic loss in pig hu sbandry in rural areas of endemic countries. Increasing the resistance to t he parasite in the obligatory host pig may help in curbing transmission. Th ree synthetic peptides based on protein sequences of the murine parasite Ta enia crassiceps, which had previously been shown to induce protection in mi ce against homologous challenge, were tested as a vaccine against T solium cysticercosis in pigs. Vaccinated and unvaccinated piglets (240 in all) wer e distributed in pairs among the peasants' households of two rural villages in Mexico in which 14% of the native pigs were cysticercotic. Ten to twelv e months later, the effect of vaccination was evaluated at necropsy. Vaccin ation decreased the total number of T solium cysticerci (98.7%) and reduced the prevalence (52.6%). The natural challenge conditions used in this fiel d trial strengthen the likelihood of successful transmission control to bot h pig and human through a large-scale pig vaccination program. We believe t his is a major contribution in anticysticercosis vaccine development as the se rather simple yet protective peptides are potentially more cost-effectiv e to produce and less variable in results than antigens that are more compl ex. (C) 2001 Elsevier Science Ltd. All rights reserved.