北京市通州区2009年流感病原学监测结果分析

Aetiological monitoring analysis of influenza in Tongzhou of Beijing in 2009

目的:分析通州区2009年流感病原学监测结果,了解流感病毒优势株的亚型变化和流感的流行趋势。方法:采集流感样病例咽拭子样品,用RT-PCR法进行核酸检测和型别鉴定,同时做病毒分离和血凝实验(HA)。结果:2009年1月份,核酸阳性检出率是57.34%(82/143),分离出病毒37株,其中36株为季节性甲1(H1N1)亚型,1株为甲3(H3N2)亚型;6、7月份抽样做分型鉴定均为甲3亚型;8月份出现新甲型H1N1毒株,8月份～12月份,其核酸阳性占甲型阳性的百分比分别是2.74%、27.08%、57.41%、94.29%和94.12%。结论:2009年通州区流感病毒流行的优势株年初为季节性甲1亚型,6月份～7月份为甲3亚型;8月份开始新甲型H1N1逐步取代其他亚型,10月份以后成为优势株;同时,流感流行的高峰月从与北京以往相似的12月份～1月份提前到10月份～11月份。

Objective：To analyze the results of etiology monitoring of influenza in Tongzhou District in 2009,and to investigate the subtypes conversion and the epidemic trend of the predominant strain of influenza virus.Methods：The throat swab samples collected from influenza-like cases were detected by using RT-PCR for detecting and genotyping the nucleic acids,and virus isolation and hemagglutination test（HA）.Results：82 of 143 throat swab samples,collected in January 2009,were positive in nucleic acid detection,and the positive rate was 57.34%.37 strains of influenza virus（36 of subtype H1N1 and 1 of subtype H3N2） were isolated.The strains of influenza virus isolated in June and July were all subtype A3（H3N2）.2009 H1N1 Flu virus（Swine Flu virus） first emerged in August,and the positive rates in influenza A positive samples from August to December were respectively 2.74%,27.08%,57.41%,94.29%,and 94.12%.Conclusion：The predominant strain of influenza was seasonal subtype A1,in Tongzhou District in early 2009.In June and July the predominant strain changed to subtype A3.2009 H1N1 Flu virus appeared from August,gradually replaced other subtypes,and become predominant strain after October.Meanwhile,the epidemic peak periods of influenza changed to October and November,which were two months in advance compared with December and next January in former years.