摘要
目的分析河北省甲型H1N1流感的流行病学特点及血凝素基因HA基因特征。方法通过中国流感监测信息系统收集河北省2011年4月至2017年3月流感及流感样病例(influenza-like illness,ILI)监测数据进行统计分析,选定期间分离的14株甲型H1N1流感毒株,对HA基因进行测序和比对分析。结果2011-2017年共检测ILI标本77 008份,甲型H1N1流感阳性2 699份,阳性率3.50%,全省11个地市均有该病毒检出,男女性别比为1.17∶1,各年龄组均可发病,检出率最高的是25~59岁组,期间共出现4次流行,近年来检出率高峰由冬季转为春季。14株甲型H1N1流感病毒的氨基酸同源性在96.9%~99.9%,分属不同的进化分支,变异氨基酸部分位于抗原决定簇,关键位点第222位未发生变化。2013年1月和12月份毒株持续变异是导致其流行的主要原因。2016、2017年的分离株与新疫苗株同源性较高(99.2%~99.5%)。结论河北省甲型H1N1流感流行具有明显的季节性,近年来感染以25~59岁年龄组为主。HA基因与其编码的氨基酸逐年变异,新疫苗株与目前流行甲型H1N1流感病毒高度同源。
Objective To analyze the epidemic characteristics of influenza A （H1N1） pdm09 and hemagglutinin （HA） gene mutations in Hehei province of China during 2011 and 2017. Methods The analysis was conduc- ted on the data collected from cases of influenza and influenza-like illness （ILL） in Hebei province of China from April 2011 to March 2017 in the Chinese National Influenza Surveillance Network. Fourteen representa rive positive strains of influenza A （H1N1） pdm09 viruses were selected. HA genes of 14 isolates were se- quenced and the genetic characterization was analyzed. Results A total of 77 008 specimens were collected and 2 699 （3.50~） were positive for influenza A （H1N1） pdm09 virus. Further analysis of the 2 699 cases of （H1N1） pdm09 showed that influenza A （H1N1） pdm09 virus were detected throughout the whole 11 re- gions. The male to female ratio was 1.17 ： 1. The highest detection rate was in the 25-29 years group. During April 2011 to March 2017, four times of influenza A （HIN1） pdm09 epidemics had been occurred, and the peak detection rate was gradually converted from winter to spring recently. The HA genes of 14 isolates shared the highest nucleic acid sequence similarity （96.9 ^-99.9 ~）. The phylogenetic analysis showed that the HA genes of all strains were in different evolutionary branches. The amino acid changes were partly located in anti- genic sites. The key amino acid position 222 did not change. The strain variations isolated from January and De cember of 2013 was the main reason for its popularity. The strains which isolated in 2016 and 2017 showed high homology （99.20/oo-99.5~/oo） with the new vaccine strain recommended by WHO. Conclusions Theprevalence of influenza A （H1N1） pdm09 in Hebei province of China showed an obvious seasonality with peaks in winter and spring. In recent years, the peak detection rate gradually switched from winter to spring, and the infections fell into the age group of 25-59 years. The HA gene and amino acid change gra
出处
《中国病毒病杂志》
CAS
2017年第4期271-276,共6页
Chinese Journal of Viral Diseases
基金
河北省卫生厅科研课题(20100221)
关键词
甲型H1N1流感病毒
流行特征
血凝素基因
序列分析
Influenza A （H1N1） pdm09
Epidemiological characteristics
Hemagglutinin genes Sequence analysis
