title: Characterization of foot-and-mouth disease virus from outbreaks in Ecuador during 2009-2010 and cross-protection studies with the vaccine strain in use in the region.
abstract: During the years 2009 and 2010 relevant epidemic waves of foot-and-mouth disease (FMD) serotype O occurred in Ecuador, representing a great drawback for the last stages of the ongoing eradication program in South America. This study describes the molecular and antigenic characterizations of 29 isolates collected from various regions in the country and their relationship to the vaccine strain. The phylogenetic tree derived from sequences spanning the complete VP(1) protein showed that, despite the widespread origin of the viruses, they were all related among themselves and to previous isolates occurring in 2008, with around 10% difference with the vaccine strain O1/Campos. The high level of sequence conservation among different isolates in the various regions of Ecuador pointed to a common origin, suggesting animal movements as possible sources of viral spread. Monoclonal antibody profiling grouped the isolates in two major reactivity patterns which differed from that of the vaccine strain. Both profiles showed loss of reactivity with the same four MAbs, three of them with neutralizing properties. Additional sites were lost in the profile representing most of the 2010s viral samples. Levels of protective antibodies induced by the vaccine against the field strains assessed by in vitro vaccine matching studies also pointed to an increased temporal pattern of loss of a protective response. Moreover, results obtained with in vivo challenge in the protection against podal generalization test in cattle, clearly indicated lack of appropriate protection of the Ecuadorian field strains by the vaccine virus in use, which in the case of a 2010 variant was observed even after revaccination.
authors.affiliation: Servicio Nacional de Sanidad y Calidad Agroalimentaria, Avda. Fleming 1653, Martínez, Argentina.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Maradei
authors.forename: Claudia
authors.initials: C
authors.lastname: Perez Beascoechea
authors.forename: Viviana
authors.initials: V
authors.lastname: Malirat
authors.forename: Gustavo
authors.initials: G
authors.lastname: Salgado
authors.forename: Cristina
authors.initials: C
authors.lastname: Seki
authors.forename: Andrea
authors.initials: A
authors.lastname: Pedemonte
authors.forename: Paula
authors.initials: P
authors.lastname: Bonastre
authors.forename: Ricardo
authors.initials: R
authors.lastname: D'Aloia
authors.forename: José L
authors.initials: JL
authors.lastname: La Torre
authors.forename: Nora
authors.initials: N
authors.lastname: Mattion
authors.forename: Jorge
authors.initials: J
authors.lastname: Rodríguez Toledo
authors.forename: Ingrid E
authors.initials: IE
authors.lastname: Bergmann
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D036022:Capsid Proteins / Q000235:genetics; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology*; D016000:Cluster Analysis; D056738:Cross Protection; D004196:Disease Outbreaks; D004484:Ecuador / Q000453:epidemiology; D005536:Foot-and-Mouth Disease / Q000453:epidemiology*; D029544:Foot-and-Mouth Disease Virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D005838:Genotype; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D012703:Serotyping; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D036022:Capsid Proteins; D012367:RNA, Viral; C442501:VP1 protein, Foot-and-mouth disease virus; D014765:Viral Vaccines