Efficacy of a high quality O 1 /Campos foot-and-mouth disease vaccine upon challenge with a heterologous Korean O Mya98 lineage virus in pigs

• Published in: Vaccine 2018-03, Vol.36 (12), p.1570
• Main Authors: Galdo Novo, S, Malirat, V, Maradei, E D, Pedemonte, A R, Espinoza, A M, Smitsaart, E, Lee, K N, Park, J H, Bergmann, I E
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Neutralizing - immunology; Antibodies, Viral - immunology; Antigens; Antigens, Viral - immunology; Cell Line; Cross Protection; Epidemics; Expectancy; Foot & mouth disease; Foot-and-Mouth Disease - prevention & control; Foot-and-Mouth Disease Virus - classification; Foot-and-Mouth Disease Virus - genetics; Foot-and-Mouth Disease Virus - immunology; Genetic analysis; Genetic Variation; Immunization; Outbreaks; Phylogeny; Pigs; Republic of Korea; Swine; Swine Diseases - prevention & control; Vaccines; Viral Vaccines - immunology; Viruses
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2018.02.015

In 2010 serotype O foot-and-mouth disease virus of the Mya98 lineage/SEA topotype spread into most East Asian countries. During 2010-2011 it was responsible for major outbreaks in the Republic of Korea where a monovalent O/Manisa vaccine (belonging to the ME-SA topotype) was applied to help control the outbreaks. Subsequently, all susceptible animals were vaccinated every 6 months with a vaccine containing the O/Manisa antigen. Despite vaccination, the disease re-occurred in 2014 and afterwards almost annually. This study focuses on the in vivo efficacy in pigs of a high quality monovalent commercial O /Campos vaccine against heterologous challenge with a representative 2015 isolate from the Jincheon Province of the Republic of Korea. Initially, viral characterizations and r determinations were performed on six viruses recovered in that region during 2014-2015, centering on their relationship with the well characterized and widely available O /Campos vaccine strain. Genetic and antigenic analysis indicated a close similarity among 2014-2015 Korean isolates and with the previous 2010 virus, with distinct differences with the O /Campos strain. Virus neutralisation tests using O /Campos cattle and pig post vaccination sera and recent Korean outbreak viruses predicted acceptable cross-protection after a single vaccination, as indicated by r values, and in pigs, by expectancy of protection. In agreement with the in vitro estimates, in vivo challenge with a selected field isolate indicated that O /Campos primo vaccinated pigs were protected, resulting in a PD50 value of nearly 10. The results indicated that good quality oil vaccines containing the O /Campos strain can successfully be used against isolates belonging to the O Mya98/SEA topotype.