title: Rapid emergence and predominance of a broadly recognizing and fast-evolving norovirus GII.17 variant in late 2014.
abstract: Norovirus genogroup II genotype 4 (GII.4) has been the predominant cause of viral gastroenteritis since 1996. Here we show that during the winter of 2014-2015, an emergent variant of a previously rare norovirus GII.17 genotype, Kawasaki 2014, predominated in Hong Kong and outcompeted contemporary GII.4 Sydney 2012 in hospitalized cases. GII.17 cases were significantly older than GII.4 cases. Root-to-tip and Bayesian BEAST analyses estimate GII.17 viral protein 1 (VP1) evolves one order of magnitude faster than GII.4 VP1. Residue substitutions and insertion occur in four of five inferred antigenic epitopes, suggesting immune evasion. Sequential GII.4-GII.17 infections are noted, implicating a lack of cross-protection. Virus bound to saliva of secretor histo-blood groups A, B and O, indicating broad susceptibility. This fast-evolving, broadly recognizing and probably immune-escaped emergent GII.17 variant causes severe gastroenteritis and hospitalization across all age groups, including populations who were previously less vulnerable to GII.4 variants; therefore, the global spread of GII.17 Kawasaki 2014 needs to be monitored.
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Martin C W
authors.initials: MC
authors.lastname: Chan
authors.affiliation: Department of Medicine and Therapeutics, Faculty of Medicine, 9/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Nelson
authors.initials: N
authors.lastname: Lee
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Tin-Nok
authors.initials: TN
authors.lastname: Hung
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Kirsty
authors.initials: K
authors.lastname: Kwok
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Kelton
authors.initials: K
authors.lastname: Cheung
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Edith K Y
authors.initials: EK
authors.lastname: Tin
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Raymond W M
authors.initials: RW
authors.lastname: Lai
authors.affiliation: Department of Paediatrics, Faculty of Medicine, 6/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: E Anthony S
authors.initials: EA
authors.lastname: Nelson
authors.affiliation: Department of Paediatrics, Faculty of Medicine, 6/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Ting F
authors.initials: TF
authors.lastname: Leung
authors.affiliation: Department of Microbiology, Faculty of Medicine, 1/F Lui Che Woo Clinical Sciences Building, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Paul K S
authors.initials: PK
authors.lastname: Chan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001315:Australia / Q000453:epidemiology; D017250:Caliciviridae Infections / Q000453:epidemiology / Q000821:virology*; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D019143:Evolution, Molecular; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology*; D005838:Genotype; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D029322:Norovirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D010802:Phylogeny; D012621:Seasons; D014764:Viral Proteins / Q000235:genetics; D055815:Young Adult
chemical_list: D014764:Viral Proteins