Characterization of a human H9N2 influenza virus isolated in Hong Kong

Citation
T. Saito et al., Characterization of a human H9N2 influenza virus isolated in Hong Kong, VACCINE, 20(1-2), 2001, pp. 125-133
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Veterinary Medicine/Animal Health",Immunology
Journal title
VACCINE
ISSN journal
0264-410X → ACNP
Volume
20
Issue
1-2
Year of publication
2001
Pages
125 - 133
Database
ISI
SICI code
0264-410X(20011012)20:1-2<125:COAHHI>2.0.ZU;2-7
Abstract
Two H9N2 viruses were isolated, for the first time, from humans in Hong Kon g in 1999. Isolation Of influenza viruses with a novel subtype of the hemag glutinin (HA) drew attention of health care authorities worldwide from the view of pandemic preparedness. Sequence analysis of the HA genes reveals th at HA of A/Hong Kong/1073/99 (H9N2) is most closely related to that of A/qu ail/HK/G1/97 (H9N2) that contains the internal genes similar to those of Ho ng Kong/97 (H5N1) viruses. Phylogenetic and antigenic analyses demonstrated the diversity among H9 HA. A/Hong Kong/1073/99 was shown to cause a respir atory infection in Syrian hamsters, suggesting that the virus can replicate efficiently in mammalian hosts. We developed a whole virion test vaccine w ith a formalin-inactivated egg-grown HK1073. Intraperitoneal administration of the vaccine twice to hamsters conferred a complete protection against c hallenge infection by the MDCK cell-grown homologous virus. Receptor specif icity of HK1073 appeared different from that of other avian influenza virus es of H9 subtype which recognize preferentially alpha -2,3 linked sialic ac id. Hemagglutination of HK1073 with guinea pig erythrocytes was inhibited b y both alpha -2,3 and alpha -2,6 linked sialic acid containing polymers. Th ese data suggested that HK1073 had acquired a broader host range, including humans. Together with data so far available, the present study suggested t hat isolation of the H9 influenza viruses from humans requires precaution a gainst the emergence of a novel human influenza. (C) 2001 Elsevier Science Ltd. All rights reserved.