title: Age-specific genetic and antigenic variations of influenza A viruses in Hong Kong, 2013-2014.
abstract: Age-specific genetic and antigenic variations of influenza viruses have not been documented in tropical and subtropical regions. We implemented a systematic surveillance program in two tertiary hospitals in Hong Kong Island, to collect 112 A(H1N1)pdm09 and 254 A(H3N2) positive specimens from 2013 to 2014. Of these, 56 and 72 were identified as genetic variants of the WHO recommended vaccine composition strains, respectively. A subset of these genetic variants was selected for hemagglutination-inhibition (HI) tests, but none appeared to be antigenic variants of the vaccine composition strains. We also found that genetic and antigenicity variations were similar across sex and age groups of ≤18 yrs, 18 to 65 yrs, and ≥65 yrs. Our findings suggest that none of the age groups led other age groups in genetic evolution of influenza virus A strains. Future studies from different regions and longer study periods are needed to further investigate the age and sex heterogeneity of influenza viruses.
authors.affiliation: Division of Epidemiology and Biostatistics, School of Public Health, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: Peihua
authors.initials: P
authors.lastname: Cao
authors.affiliation: Division of Epidemiology and Biostatistics, School of Public Health, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: Chit-Ming
authors.initials: CM
authors.lastname: Wong
authors.affiliation: Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: Kwok-Hung
authors.initials: KH
authors.lastname: Chan
authors.affiliation: Department of Biostatistics, School of Public Health and Key Laboratory of Public Health Safety, Fudan University, Shanghai, China.
authors.forename: Xiling
authors.initials: X
authors.lastname: Wang
authors.affiliation: Division of Epidemiology and Biostatistics, School of Public Health, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: King-Pan
authors.initials: KP
authors.lastname: Chan
authors.affiliation: Division of Public Health Laboratory Sciences, School of Public Health, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: Joseph Sriyal Malik
authors.initials: JS
authors.lastname: Peiris
authors.affiliation: Division of Public Health Laboratory Sciences, School of Public Health, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: Leo Lit-Man
authors.initials: LL
authors.lastname: Poon
authors.affiliation: School of Nursing, The Hong Kong Polytechnic University, Hong Kong SAR, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000956:Antigens, Viral / Q000235:genetics / Q000276:immunology; D005260:Female; D006723:Hong Kong; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D053122:Influenza A Virus, H3N2 Subtype / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D007251:Influenza, Human / Q000453:epidemiology* / Q000235:genetics / Q000821:virology; D008297:Male; D008875:Middle Aged; D062606:Tertiary Care Centers; D055815:Young Adult
chemical_list: D000956:Antigens, Viral