中山市2014年麻疹病毒分子生物学特征分析

Molecular characteristics analysis of measles virus in 2014,Zhongshan City

目的麻疹病毒学监测数据表明,H1基因型是中国本土优势基因型。本研究分析广东省中山市2014年麻疹病毒分子生物学流行特征,为麻疹消除策略修订或制定提供数据依据。方法采集广东省中山市2014-01-01-2014-12-31全年疑似患者的急性期咽拭子,通过RT-PCR和基因测序分析N基因碳末端450个核苷酸片段;应用BLASTn对序列进行相似性检索,分析麻疹病毒基因特征,并与WHO推荐的参考株进行对比;采用MEGA对麻疹核蛋白核苷酸构建NJ种系进化树。结果广东省中山市麻疹监测网络实验室收检疑似麻疹咽拭子306份,核酸阳性213份,阳性率69.61%。对213份咽拭子核酸阳性样品进行病毒分离,共分离出98株麻疹病毒,病毒分离率46.01%。除zhongshan2014-5为D8基因型外,其他均是H1基因型。zhongshan2014-5与越南病毒株(Viet Nam:Ho Chi Minh CityAB928200)序列同源性100%,属于D8型。结论 H1基因型是中山市2014年流行麻疹病毒的绝对优势基因型,中山市首次发现输入性D8型麻疹病毒感染病例。

OBJECTIVE Measles virological surveillance data indicates that the H1 genotype is the dominant genotype in China.In order to understand the molecular biological epidemic characteristics of measles virus in Zhongshan City in 2014,this study was carried out.METHODS Throat swab from the patient were collected during acute phase after infection.Samples were assayed for preparing total viral RNA.About 450 nucleotides of the 3’terminus of nucleoprotein(N)gene were amplified with RT-PCR and sequenced.The sequence of the amplicons was analyzed and characterized with BLASTn,aligned with the WHO reference strain.Phylogenetic tree analysis of this sequence was operated with Neighbor-Joining method performed by MEGA.RESULTS Totally 306 throat swab were collected to detect virus nucleic acid,213 were positive,the positive rate was 69.61%.98 strains of measles virus were isolated for the 213 nucleic acid positive throat swab samples,and the success of isolation rate was 46.01%.Sequence of about 450 nucleotides of the 3′terminus of nucleoprotein(N)gene was obtained and uploaded to GenBank(KJ994346).Results of alignment showed that it formed a same clade with WHO reference strain(Manchester.UNK/30.94-AF280803),D8 genotype.Multi-sequence alignment analysis indicated that the nucleotide sequence shared 100%,96%identity with Vietnam Strain(Viet Nam Ho Chi Minh City-AB928200).CONCLUSIONS H1 genotype was the dominant genotype of measles virus in Zhongshan City in 2014.The newly imported measles virus strain is genotype D8,firstly found in Zhongshan City.