Age-specific genetic and antigenic variations of influenza A viruses in Hong Kong, 2013–2014
نویسندگان
چکیده
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.
منابع مشابه
Molecular Identification of Pre-Existing Immunityin Human against H9N2 Influenza Viruses Using HLA-A*0201 Binding Peptides
Background and Aims: The contribution genetic and antigenic diversity of H9N2 influenza viruses in evading from immune responses, cytotoxic T lymphocytes (CTL) epitopes in hemagglutinin (HA) protein restricted by HLA binding peptides was identified. Materials and Methods: Phylogenetic analyses were carried out for all of full length HA and deduced amino acid sequences of H9N2 viruses available ...
متن کاملتغییرات ژنتیکی ویروس و فرار از سامانه ایمنی، چالشهای پیشرو علیه آنفلوآنزا: مقاله مروری
The spread of influenza viruses in multiple bird and mammalian species is a worldwide serious threat to human and animal populations' health and raise major concern for ongoing pandemic in humans. Direct transmission of the avian viruses which have sialic acid specific receptors similar to human influenza viruses are a warning to the emergence of a new mutant strain that is likely to share mole...
متن کاملAntigenic Variation of the Haemagglutinin Gene of the Influenza A (H1N1) pdm09 Virus Circulating in Shiraz, February-April 2013
Background: A new pandemic influenza A (H1N1) emerged in April 2009, causing considerable morbidity and mortality. Since mutations in the haemagglutinin (HA) may influence the antigenicity and pathogenicity of the virus, continued epidemiological and molecular characterization for the effective control of pandemic flu and developing of more appropriate vaccine is crucial. Objective: To monitor ...
متن کاملPopulation-Based Hospitalization Burden of Influenza A Virus Subtypes and Antigenic Drift Variants in Children in Hong Kong (2004–2011)
OBJECTIVES We aim to document and analyze influenza hospitalization burden in light of antigenic changes in circulating influenza viruses in Hong Kong. METHODS The pediatric age-specific rates of influenza A hospitalization in Hong Kong for 2004-2011 which encompassed the emergence of H1N1pdm09 were extrapolated from admissions to 2 hospitals that together catered for 72.5% of all pediatric a...
متن کاملNeuraminidase gene sequence analysis of avian influenza H9N2 viruses isolated from Iran
Influenza A viruses possesses two virion surface glycoproteins including haemagglutinin (HA) and neuraminidase (NA). The NA plays an important role in viral replication and promotes virus release from infected cells and facilitates virus spread throughout the body. To find out any genomic changes that might be occurred on NA gene of avian influenza circulating viruses, we have genetically analy...
متن کامل