Abstract：Objective To define the genetic characteristics of hemagglutinin of influenza A (H1N1) virus from 2013 to 2014 and of influenza A (H3N2) virus from 2013 to 2015 as well as their antigen mutations in Tongchuan City by bioinformatics data-base and tools. Methods Nasopharyngeal swab specimens were collected from patients with influenza-like illness in sentinel hospitals in Tongchuan City. Influenza viruses were isolated with MDCK cells. Hemagglutinin genomic sequences of parts of type A H1N1 and H3N2 influenza viruses were amplified and purified by RT-PCR, and then sequenced and analyzed with phylogenetic tree using MEGA software. Results A total of 2,333 suspected influenza specimens were detected for nucleic acid in Tongchuan City from 2013 to 2015, and 476 were positive for influenza viruses, with the positive rate of 20.40%. Comparison of amino acid sequences of four strains of H1N1 virus with A/California/07/2009 (H1N1) vaccine strain recommended by WHO showed that there were a total of 11 amino acid mutations, with 3 mutations occurring in the antigenic determinant. As for the amino acid sequences of three strains of type A H3N2 influenza viruses, when they were compared with A/Victoria/361/2011(H3N2) vaccine strains for the northern hemisphere in 2014-2015 recommended by WHO, 9 amino acid mutations were found, with 3 mutations in the antigenic determinant. When they were compared with A/Texas/50/2012 (H3N2) vaccine strains for the northern hemisphere in 2014-2015 recommended by WHO, 10 amino acid mutations were found, with 5 mutations in the antigenic determinant. Conclusions Amino acid mutations occur in the hemagglutinin antigenic sites in type A H1N1 and H3N2 influenza viruses prevalent in Tongchuan City in 2013-2015, which results in antigenic drift.
李俊, 苏翠, 陈晓宁, 刘新利, 李悦玲. 铜川市2013-2015年A型流感病毒HA基因特性研究[J]. 实用预防医学, 2016, 23(12): 1451-1454.
LI Jun, SU Cui, CHEN Xiao-ning, LIU Xin-li, LI Yue-ling. Characteristics of HA gene of influenza A virus in Tongchuan City, 2013-2015. , 2016, 23(12): 1451-1454.
2016, Vol. 23 
