Vosloo, WilnaNguyen, Thi Thu HongFosgate, Geoffrey TheodoreMorris, Michelle JacquelineWang, JianningKim, Van PhucQuach, Vo NgonLe, Thi Thu PhuongDang, HungTran, Xuan HanhVo, Van HungLe, Thi Quynh AnhSinganallur, Balasubramanian Nagendrakumar2015-09-302015-09-302015-06Vosloo, W, Nguyen, TTH, Fosgate, TG, Morris, MJ, Wang, J, Kim, VP, Quach, VN, Le, TTP, Dang, H, Tran, XH, Vo, VH, Le, TQA, Mai, TMT, Le, TVQ, Ngo, TL & Singanallur, BN 2015, 'Efficacy of a high potency O1 Manisa monovalent vaccine against heterologous challenge with a FMDV O Mya98 lineage virus in pigs 4 and 7 days post vaccination', Vaccine, vol. 33, no. 24, pp. 2778-2785.0264-410X (print)1873-2518 (online)10.1016/j.vaccine.2015.04.045http://hdl.handle.net/2263/50099Early protection with a high potency (>6PD50) foot-and-mouth disease (FMD) O1 Manisa (Middle-EastSouth Asia lineage) vaccine against challenge with O/VIT/2010 (O Mya98 lineage) was tested in pigs. Only two pigs that were vaccinated seven days prior to challenge had any demonstrable antibodies as a result of vaccination at the time of challenge. However, 80% and 60% of pigs that were vaccinated seven and four days prior to coronary band challenge were protected. Vaccination significantly reduced the amount of virus excreted in nasal swabs, saliva and faeces compared to unvaccinated and infected controls. Virus and viral RNA could be detected in some pigs until termination of the experiment 14 days after challenge.Antibodies to the non-structural proteins (NSP) were detected in only one pig that was challenged four days post vaccination (dpv) and transiently in two pigs that were challenged seven dpv at only one timepoint. For each vaccine and control group, a group of unvaccinated pigs were kept in the same room but with no direct contact with the infected pigs to determine whether vaccination prevented transmission. Despite the presence of live virus and viral RNA in these indirect contact pigs, the groups in contact with the vaccinated and infected pigs did not develop clinical signs nor did they sero-convert. Contact pigs in the same room as unvaccinated challenged controls did show signs of disease and virus infection that resulted in sero-conversion to the NSP. A breach of the wall that separated the two groups at nine days post challenge might have contributed to this finding. This study showed that high potency vaccine can provide protection to pigs soon after vaccination and that aerosol transmission within rooms is a rare event.en© 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-NDlicense (http://creativecommons.org/licenses/by-nc-nd/4.0/).FMD vaccineHigh potencyHeterologous challengePigsEarly protectionFoot-and-mouth diseaseNon-structural proteins (NSP)Foot-and-mouth disease (FMD)Article