title: Genetic and antigenic characterisation of serotype A FMD viruses from East Africa to select new vaccine strains.
abstract: Vaccine strain selection for emerging foot-and-mouth disease virus (FMDV) outbreaks in enzootic countries can be addressed through antigenic and genetic characterisation of recently circulating viruses. A total of 56 serotype A FMDVs isolated between 1998 and 2012, from Central, East and North African countries were characterised antigenically by virus neutralisation test using antisera to three existing and four candidate vaccine strains and, genetically by characterising the full capsid sequence data. A Bayesian analysis of the capsid sequence data revealed the viruses to be of either African or Asian topotypes with subdivision of the African topotype viruses into four genotypes (Genotypes I, II, IV and VII). The existing vaccine strains were found to be least cross-reactive (good matches observed for only 5.4-46.4% of the sampled viruses). Three bovine antisera, raised against A-EA-2007, A-EA-1981 and A-EA-1984 viruses, exhibited broad cross-neutralisation, towards more than 85% of the circulating viruses. Of the three vaccines, A-EA-2007 was the best showing more than 90% in-vitro cross-protection, as well as being the most recent amongst the vaccine strains used in this study. It therefore appears antigenically suitable as a vaccine strain to be used in the region in FMD control programmes.
authors.affiliation: The Pirbright Institute, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK.
authors.forename: Fufa D
authors.initials: FD
authors.lastname: Bari
authors.affiliation: The Pirbright Institute, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK.
authors.forename: Satya
authors.initials: S
authors.lastname: Parida
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR, Lelystad, The Netherlands.
authors.forename: Tesfaalem
authors.initials: T
authors.lastname: Tekleghiorghis
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR, Lelystad, The Netherlands.
authors.forename: Aldo
authors.initials: A
authors.lastname: Dekker
authors.affiliation: Foot-and-Mouth Disease Laboratory, Embakasi, Nairobi, Kenya.
authors.forename: Abraham
authors.initials: A
authors.lastname: Sangula
authors.affiliation: The Pirbright Institute, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK; Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Reeve
authors.affiliation: Boyd Orr Centre for Population and Ecosystem Health, Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Haydon
authors.affiliation: The Pirbright Institute, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Paton
authors.affiliation: The Pirbright Institute, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK. Electronic address: mana.mahapatra@pirbright.ac.uk.
authors.forename: Mana
authors.initials: M
authors.lastname: Mahapatra
mesh_terms: D000351:Africa, Eastern; D000818:Animals; D000956:Antigens, Viral / Q000276:immunology*; D001499:Bayes Theorem; D036022:Capsid Proteins / Q000235:genetics; D002417:Cattle; D029544:Foot-and-Mouth Disease Virus / Q000145:classification* / Q000276:immunology*; D005838:Genotype; D009500:Neutralization Tests; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D017423:Sequence Analysis, RNA; D065288:Serogroup
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D012367:RNA, Viral
keywords: Antigenic sites; Capsid sequence; FMD virus; Neutralising epitopes; Polyclonal antibodies; Vaccine strain selection