title: Dynamics and evolution of highly pathogenic porcine reproductive and respiratory syndrome virus following its introduction into a herd concurrently infected with both types 1 and 2.
abstract: Since its first emergence in Thailand in late 2010, highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) has caused sporadic outbreaks on Thai swine farms. The objective of this study was to investigate the dynamics and evolution of PRRSV in a herd experiencing an HP-PRRSV outbreak. Following its introduction, HP-PRRSV caused severe outbreaks and subsequently established persistent infection in the herd, resulting in the emergence of a novel cluster of type 2 (North American, NA) isolates. HP-PRRSV co-existed with type 1 (European, EU) isolates without influencing their development. In contrast, HP-PRRSV influenced the evolution of the type 2 (NA) isolates by increasing diversity through the addition of a novel cluster and influencing the evolution of other viral clusters previously existing in the herd. Recombination between the endemic and emerging isolates was observed. The recombinants, however, disappeared and were not able to survive in the herd. The results of this study suggest that the introduction of HP-PRRSV to a herd results in an increased diversity of genetically related isolates and persistent HP-PRRSV infection.
authors.affiliation: Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Puwich
authors.initials: P
authors.lastname: Chaikhumwang
authors.affiliation: Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Angkana
authors.initials: A
authors.lastname: Tantituvanont
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Bangkok 10330, Thailand.
authors.forename: Thitima
authors.initials: T
authors.lastname: Tripipat
authors.affiliation: Genome Institute, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand.
authors.forename: Pavita
authors.initials: P
authors.lastname: Tipsombatboon
authors.affiliation: Genome Institute, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand.
authors.forename: Jittima
authors.initials: J
authors.lastname: Piriyapongsa
authors.affiliation: Department of Veterinary Microbiology, Faculty of Veterinary Science, Bangkok 10330, Thailand. Electronic address: dachrit@gmail.com.
authors.forename: Dachrit
authors.initials: D
authors.lastname: Nilubol
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D019318:Porcine Reproductive and Respiratory Syndrome / Q000453:epidemiology* / Q000821:virology*; D019316:Porcine respiratory and reproductive syndrome virus / Q000145:classification* / Q000235:genetics* / Q000472:pathogenicity; D016415:Sequence Alignment; D034421:Sus scrofa / Q000821:virology*; D013552:Swine; D013785:Thailand
keywords: Evolution; Highly pathogenic PRRSV; ORF5; PRRSV; Thailand