title: Genetic characterisation of Porcine circovirus type 2 (PCV2) strains from feral pigs in the Brazilian Pantanal: An opportunity to reconstruct the history of PCV2 evolution.
abstract: Since its discovery, Porcine circovirus type 2 has emerged as one of the most relevant swine infectious diseases, causing relevant economic losses for the pig industry. While four genotypes were identified, only three (PCV2a, PCV2b and PCV2d) are currently circulating and display a worldwide distribution. Another genotype, PCV2c, has been described only once in Danish archive samples collected between 1980 and 1990. In addition to commercial pigs, PCV2 has been demonstrated to infect wild boars and other wild species, which can potentially serve as a reservoir for domestic populations. In this study, eight sequences obtained from feral pigs in the Pantanal region (Mato Grosso do Sul State, Brazil) were compared with reference sequences and other Brazilian sequences, and the results revealed remarkable genetic diversity, with all four genotypes currently recognised being detected (PCV2a, PCV2b, PCV2c and PCV2d). This finding represents a remarkable discovery, as it is the first detection of PCV2c since 1990 and the first-ever detection of PCV2c in live animals. The peculiar population history and ecological scenario of feral pigs in the Pantanal coupled with the complex, and still only partially known relationship of feral pigs with other PCV2 susceptible species (i.e., domestic pigs, wild boars and peccaries), open exciting questions concerning PCV2 origin and evolution. Overall, the results of the present study led us to form the following hypothesis: the PCV2 strains found in feral pigs may be the last descent of the strains that circulated among European pigs in the past, or they may have infected these feral pigs more recently through a bridge species.
authors.affiliation: University of Padua, Padua, Italy. Electronic address: giovanni.franzo@unipd.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Franzo
authors.affiliation: The Pirbright Institute, Pirbright, Woking, UK.
authors.forename: Martí
authors.initials: M
authors.lastname: Cortey
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil;
authors.forename: Alessandra Marnie Martins Gomes
authors.initials: AM
authors.lastname: de Castro
authors.affiliation: Empresa Brasileira de Pesquisa Agropecuária - Embrapa Pantanal, Corumbá, MS, Brazil.
authors.forename: Ubiratan
authors.initials: U
authors.lastname: Piovezan
authors.affiliation: Laboratório de Ixodologia, Faculdade de Medicina Veterinária, Universidade Federal de Uberlândia, MG, Brazil.
authors.forename: Matias Pablo Juan
authors.initials: MP
authors.lastname: Szabo
authors.affiliation: University of Padua, Padua, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Drigo
authors.affiliation: Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, Departament de Sanitat i d'Anatomia Animals, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Segalés
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil;
authors.forename: Leonardo José
authors.initials: LJ
authors.lastname: Richtzenhain
mesh_terms: D000818:Animals; D001483:Base Sequence; D001938:Brazil; D017925:Circovirus / Q000235:genetics*; D019143:Evolution, Molecular; D014644:Genetic Variation; D005838:Genotype; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D013552:Swine / Q000821:virology*; D053833:Wetlands
keywords: Brazil; Feral pigs; Phylogeny; Porcine circovirus type 2 (PCV2)