医院环境中甲型流感病毒气溶胶检测及其HA基因特征分析

Detection of influenza A virus in aerosols in hospitals and analysis of the HA gene

目的了解甲型流感病毒气溶胶在医院环境中的存在情况，分析甲型流感病毒的HA基因变异特征。方法选择江苏省淮安市综合性医院（医院A）及儿童专科医院（医院B）各1家，利用BIOCapturer-5仪采集医院门诊输液中心4个位点（入口、出口、中央走廊、输液台附近）的环境气溶胶；医院A和医院B分别采集气溶胶样本16份，共计采集32份；并分别采集到发热门诊就诊的7份病人咽拭子标本，共计14份。以实时荧光RT—PCR及巢式RT—PCR法分别进行流感病毒的快速检测及甲型流感病毒HA基因扩增、测序及构建系统发生树并进行HA基因特征分析。结果医院A环境中检测到1份H3N2流感病毒气溶胶，在病人咽拭子中检测到6份H3N2流感病毒和1份甲型H1N1流感病毒；医院B环境中检测到1份甲型H1N1流感病毒性气溶胶，在病人咽拭子中检测到3份H3N2流感病毒和2份甲型H1N1流感病毒。H3N2流感病毒气溶胶样本A／Environment-air／Huai’an／A1／2017与咽拭子样本A／Huai’an／TA1／2017的核苷酸同源性最高，为99．8％；甲型H1N1流感病毒气溶胶样本A／Environment-air／Huai’an／B1／2017与咽拭子样本A／Huai’an／TA7／2017的核苷酸同源性最高，为100．0％。结论医院环境中易存在甲型流感病毒污染，对医院环境中气溶胶进行流感病毒监测有助于了解流感病毒在人群中的流行情况；与甲型H1N1流感病毒相比，H3N2流感病毒分离株的HA基因存在基因多样性。

Objective To understand the contamination condition of aerosols in hospitals by influenza virus and to analyze the the viral etiology of influenza A virus based on HA gene. Methods Four sites of out-patient infusion center were selected for collecting aerosol samples both in general hospital （hospital A） and pediatric hospital （hospital B） in Huai＇an of Jiangsu province. Thirty-two aerosol samples were collected by BIO Capturer-5, 16 samples from each of the two hospitals in Huai＇an. Fourteen nasopharyngeal swab samples from patients in fever clinics were collected, 7 samples per hospital. All samples were rapidly detected by real-time RT-PCR. The target HA gene was obtained by mean of nested RT-PCR and were sequenced. The genetic and phylogenetic analysis based on HA genes was computed. Results In hospital A, influenza A （H3N2） virus was detected from 1 aerosol sample and in 6 nasopharyngeal swab samples. Influenza A （H1N1） pdm09 was found in 1 nasopharyngeal swab sample. In hospital B, influenza A （H1N1） pdm09 was found in 1 aerosol sample and in 2 nasopharyngeal swab samples while influenza A （H3N2） virus was found in 3 nasopharyngeal swab samples. Influenza A （H3N2） virus in aerosol samples （A/Environment-air/Huai＇an/A1/2017） showed the highest nucleotide identity （99.8%） with the strain A/Huai＇an/TA1/2017 from nasopharyngeal swab samples, and Influenza A （H1N1） pdm09 in aerosol samples （A/Environment-air/Huai＇an/B1/2017） was related closely to the strain A/Huai＇an/TA7/2017 isolated from nasopharyngeal swab samples. Conclusions There was indoor air contamination by influenza A virus in both hospitals. It was helpful to know the prevalence of influenza virus in the population by surveying aerosol of hospital for influenza virus. As compared to influenza A （H 1N1） pdm09 isolates, there was genetic diversity in HA gene of H3N2 viral isolates.