Original Article
Analysis of HA1 gene of influenza A H1N1 pdm09 virus from a clustered human cases
Pengfei Yang, Qingli Yan, Xuezheng Ma, Liping Zhang, Wei Zhen, Chuncheng Liu, Yadong Xing, Haibo Yao, Nanjiang He, Kongxin Hu
Published 2017-02-28
Cite as Chinese J Exp Clin Virol, 2017, 31(1): 42-46. DOI: 10.3760/cma.j.issn.1003-9279.2017.01.009
Abstract
ObjectiveTo understand the viral etiology of a clustered case of human infection outbreak in the middle school of Huai’an city.
MethodsNasopharyngeal swab samples from patients were collected and rapidly detected by Real-time RT-PCR and the target virus isolated in cells. Furthermore, HA1 segments of target virus were amplified by RT-PCR and sequenced. The genetic and phylogenetic analysis based on HA1 genes was computed.
ResultsInfluenza A(H1N1)pdm09 viral nucleic acid in 11 nasopharyngeal swab samples from patients in the outbreak were positive. Compared to the vaccine strains A/California/07/2009, the Huai’an isolates, nucleotide identity was 97.7%-98.1%, and amino acid identity was 96.6%-97.4%. Phylogenetic analysis of HA1 segment sequences indicated that the Huai’an strains from the outbreak were related closely to the viruses isolated in the year of 2014. Sequence analysis indicated that the Huai’an isolates had no amino acid substitution in the receptor binding sites and glycosylation sites, while in the Ca1 of antigenic determinant of HA1 the Huai’an isolates had an amino acid substitution of S for T at 220.
ConclusionsThe pathogen of the clustered case of human infection was Influenza A(H1N1)pdm09 virus. Though the Huai’an isolates had one animo acid substitution in the Ca1 of antigenic determinant, the antigenicity characteristic remained unchanged.
Key words:
A clustered case; Influenza A(H1N1)pdm09 virus; HA1 gene; Phylogenetic analysis; Amino acid substitution
Contributor Information
Pengfei Yang
Huai’an Center for Disease Control and Prevention, Huai’an 223001, China
Qingli Yan
Huai’an Center for Disease Control and Prevention, Huai’an 223001, China
Xuezheng Ma
Chinese Academy of Inspection and Quarantine, Institute of Health Quarantine, 100123 Beijing, China
Liping Zhang
Chinese Academy of Inspection and Quarantine, Institute of Health Quarantine, 100123 Beijing, China
Wei Zhen
National Institute for Viral Disease Control and Prevention, China CDC, 102206 Beijing, China
Chuncheng Liu
Huai’an Center for Disease Control and Prevention, Huai’an 223001, China
Yadong Xing
Huai’an Center for Disease Control and Prevention, Huai’an 223001, China
Haibo Yao
Huai’an Center for Disease Control and Prevention, Huai’an 223001, China
Nanjiang He
Huai’an Center for Disease Control and Prevention, Huai’an 223001, China
Kongxin Hu
Chinese Academy of Inspection and Quarantine, Institute of Health Quarantine, 100123 Beijing, China
