Immunogenic spectrum of Foot-and-Mouth Disease O1/campos South American strain against currently circulating Asian topotypes. Efficacy against challenge with recent O/SKR/Jincheon field isolate

MATTION, N; JAEJO, K; SMITSAART, E.; MALIRAT V; TAFFAREL, A; HAM, A; ESPINOZA, A.M.; GALDO NOVO, S.; BERGMANN I.E.; JIDA, C; PEDEMONTE, A.R.; MARADEI, E.

Incheon

Encuentro; 2017 GFRA: Global Foot-and-Mouth Disease Research Alliance. SCIENTFIC MEETING In: Incheon, Seoul, Republic of Korea.; 2017

Global Foot-and-Mouth Disease Research Alliance

Identifying vaccine strains to control outbreaks of foot-and-mouth disease (FMD) virus thatcould spread to new regions is essential for contingency plans. FMD is endemic in much ofAsia and spread of viruses from these regions caused devastating epidemics during the pastdecade, even reaching very distant regions and impacting extra-continental countries whichhad been free of the disease for decades. In this study the antigenic/immunogenicrelationships of the South American O1/Campos vaccine strain with representative isolates ofthe three currently active Asian O topotypes: South East Asia (SEA), Middle East South Asia(ME-SA) and Cathay are reported. Virus neutralization tests using O1/Campos post-vaccinationsera derived from cattle and pigs predicted for both species acceptable cross-protection, evenafter single vaccination, established by r1 values and by expectancy of protection usingmonovalent or polyvalent vaccines. In addition, genetic, antigenic and immunogeniccharacterization of viruses collected during the 2014-2015 epidemic in the Republic of SouthKorea (Jincheon Province), indicated close similarities with the O/SK 2010 virus (SEAtopotype). Further in vivo challenge studies in the PD 50% trial clearly indicated, in agreementwith the in vitro trials, that O1/Campos primo vaccinated pigs were properly protected againstone of the 2014-2015 field isolates. The results indicate high potency oil vaccines containingthe O1/Campos strain can successfully be used against Asian isolates, expanding the scope ofO1/Campos strain included in vaccine banks to control emergencies caused by Asian viruses,even on single-dose vaccination, and to cover the need of effective vaccines in Asia duringsystematic vaccination.