2011-2015年四川省流感监测结果分析

目的 了解2011-2015年四川省流感流行情况,为制定流感防制策略提供依据。方法 收集流感样病例（ILI）及病原学监测数据、流感/ILI 暴发疫情资料并分析。结果 四川省ILI%有明显冬春和夏季高峰,但冬春高峰较全国其他地区提前5周。2011-2015年共采集ILI咽拭子标本68281份,核酸检测阳性率11.63%,以2012年最高（15.36%）,各年度标本核酸阳性率有统计学差异（P ＜0.001）;阳性标本集中在1-2月、7-8月以及11-12月,各月份标本核酸阳性率有显著性差异（P ＜0.001）;2011-2015年我省H3N2亚型、B型、甲型H1N1流感交替流行,且毒株亚型时间分布与全国监测结果一致;ILI%与标本核酸阳性率高峰时间吻合,二者呈正相关（r=0.277,P ＜0.001）;报告流感/ILI暴发疫情34起,97.06%发生在学校和托幼机构。结论 我省ILI与流感病毒活动趋势一致,有明显冬春和夏季高峰;儿童和老人是防控重点对象需强化流感疫苗接种;学校是暴发疫情重点关注场所;需加强流感病毒基因检测,并结合ILI综合分析,以更客观反映流感病毒活跃程度、准确预测流行趋势。

Influenza surveillance analysis in Sichuan: 2011-2015

Objective To understand the epidemiological characteristics of influenza in Sichuan Province,so as to provide the scientific basis for the prevention of influenza. Methods Collect the data of influenza-like illness(ILI)with the results of epidemiology,etiology and influenza outbreaks,and conduct the analysis. Results The ILI% had the obvious peaks in winter and summer,but winter peak compared to other parts of the whole country 5 weeks in advance. We collected 68281 samples of throat swab samples from 2011 to 2015. The positive rate of nucleic acid detection was 11.63%,and the highest one was in 2012(15.36%). Meanwhile,the positive rate of nucleic acid in each year was statistically significant(P<0.001). The positive specimens were concentrated in the year of 1-2 months,7-8 months and 11-12 months,and the positive rate of each month in nucleic acid samples had a significant difference(P<0.001). The H3N2,B and A(H1N1)sub-type of influenza were alternately prevalent during 2011-2015 in our province,and the temporal distribution of epidemic situation and subtype strains was in accordance with the national monitoring results. Spearman correlation analysis indicated that there was the positive correlation between the ILI% and the positive rate of nucleic acid samples(r=0.277,P<0.001). 34 outbreaks of influenza/ILI were reported,and 97.06% of outbreaks occurred in schools and kindergartens. Conclusion The ILI prevalence is consistent with the trend of influenza virus activity in Sichuan Province. There are obviously epidemic peaks in winter and summer. The children and the elderly people are the focus of prevention and control,so we must strengthen the influenza vaccination. The schools are the focus of the epidemic places on outbreaks. The influenza virus detection and genetic analysis should be strengthened,and combined with ILI trend analysis,so as to reflect our province influenza virus active degree more objectively and predict the trend of influenza more accurately.