title: The emergence and evolution of the novel epidemic norovirus GII.4 variant Sydney 2012.
abstract: Norovirus is the leading cause of acute gastroenteritis with most infections caused by GII.4 variants. To understand the evolutionary processes that contribute to the emergence of GII.4 variants, we examined the molecular epidemiology of norovirus-associated acute gastroenteritis in Australia and New Zealand from 893 outbreaks between 2009 and 2012. Throughout the study GII.4 New Orleans 2009 was predominant; however, during 2012 it was replaced by an emergent GII.4 variant, Sydney 2012. An evolutionary analysis of capsid gene sequences was performed to determine the origins and selective pressures driving the emergence of these recently circulating GII.4 variants. This revealed that both New Orleans 2009 and Sydney 2012 share a common ancestor with GII.4 Apeldoorn 2007. Furthermore, pre-epidemic ancestral variants of each virus were identified up to two years before their pandemic emergence. Adaptive changes at known blockade epitopes in the viral capsid were also identified that likely contributed to their emergence.
authors: Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Biological Sciences and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia; School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia.
authors: John-Sebastian
authors: JS
authors: Eden
authors: The Institute of Environmental Science and Research Ltd (ESR), Porirua, New Zealand.
authors: Joanne
authors: J
authors: Hewitt
authors: School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia; Molecular Laboratory, Department of Pathology, Singapore General Hospital, Singapore.
authors: Kun Lee
authors: KL
authors: Lim
authors: Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam; Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.
authors: Maciej F
authors: MF
authors: Boni
authors: Virology Division, Department of Microbiology, SEALS, Prince of Wales Hospital, Randwick, NSW, Australia.
authors: Juan
authors: J
authors: Merif
authors: The Institute of Environmental Science and Research Ltd (ESR), Porirua, New Zealand.
authors: Gail
authors: G
authors: Greening
authors: Microbiology and Infectious Diseases, SA Pathology, Adelaide, SA, Australia.
authors: Rodney M
authors: RM
authors: Ratcliff
authors: Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Biological Sciences and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
authors: Edward C
authors: EC
authors: Holmes
authors: School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia.
authors: Mark M
authors: MM
authors: Tanaka
authors: School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia; Virology Division, Department of Microbiology, SEALS, Prince of Wales Hospital, Randwick, NSW, Australia; School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.
authors: William D
authors: WD
authors: Rawlinson
authors: School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia. Electronic address: p.white@unsw.edu.au.
authors: Peter A
authors: PA
authors: White
mesh_terms: D000595:Amino Acid Sequence; D001315:Australia / Q000453:epidemiology; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics; D058872:Epidemics; D019143:Evolution, Molecular; D005759:Gastroenteritis / Q000453:epidemiology* / Q000821:virology; D005838:Genotype; D006801:Humans; D008969:Molecular Sequence Data; D055820:New Orleans / Q000453:epidemiology; D009520:New Zealand / Q000453:epidemiology; D029322:Norovirus / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D036022:Capsid Proteins
keywords: Emergence; Evolution; Gastroenteritis; Norovirus; Sydney 2012