北京地区10年间住院患儿肺炎支原体感染流行特征分析

Epidemiological characteristics of Mycoplasma pneumoniae infection in hospitalized children in Beijing : 10 - year retrospective analysis

目的探讨北京地区儿童肺炎支原体(Mycoplasma pneumoniae,MP)感染的季节、年龄、性别分布情况,从而进一步分析MP的感染流行特征。方法收集2006年1月至2015年12月在首都儿科研究所附属儿童医院呼吸科住院的社区获得性肺炎患儿呼吸道标本4 271例,采用快速DNA提取试剂盒提取DNA,并利用针对MP 16S rRNA及串联重复位点Mpn16的特异性引物进行巢式聚合酶链式反应(PCR)扩增,检测MP。结果4 271例标本中,经PCR检测为MP阳性的1 042例,阳性检出率为24.4%(1 042/4 271例)。10年间共出现3次MP的暴发流行(2006年至2007年,2012年至2013年,2015年),流行年阳性检出率可高达44.6%,非流行年最低13.0%。春夏秋冬四季MP阳性检出率分别为21.2%(217/1 022例)、22.0%(230/1 044例)、28.9%(320/1 108例)和25.1%(275/1 097例),每年4月至5月和8月至9月可见小流行高峰,秋季MP感染率明显高于其他3季(χ^2=16.50、13.30、4.07,均P<0.05)。各年龄组儿童的阳性检出率分别为<1岁组10.6%(69/651例),1~2岁组17.5%(216/1 233例),3~6岁组28.5%(369/1 294例),>7岁组35.5%(388/1 093例)。学龄前期及学龄期儿童的阳性检出率[31.7%(757/2 387例)]高于婴幼儿[15.1%(285/1 884例)],差异有统计学意义(χ^2=157.0,P<0.05)。女童MP的阳性检出率[28.3%(481/1 699例)]明显高于男童[21.8%(561/2 572例)],差异有统计学意义(χ^2=23.4,P<0.05),在流行年这种差异更明显。结论北京地区儿童MP感染呈现秋冬季大高峰和夏季小高峰的双峰现象;随年龄增长,MP的阳性检出率增高,学龄前期及学龄期儿童、特别是女童为MP感染高发人群。MP感染的流行可能与长时间封闭、半封闭生活习惯密切相关。

Objective To investigate the season, age and gender distribution of Mycoplasma pneumoniae (MP) infection in children in Beijing, and to analyze the epidemiological characteristics of MP infection. Methods A total of 4 271 children with community acquired pneumonia hospitalized at the Respiratory Department of Children′s Hospital Affiliated to Capital Institute of Pediatrics were collected between January 2006 and December 2015.MP 16S rRNA and tandem repeat locus-Mpn16 were amplified by nested polymerase chain reaction(PCR). Results Among 4 271 specimens, 1 042 were positive for MP by PCR, and the positive rate was 24.4%(1 042/4 271 cases). There were 3 MP outbreaks (2006-2007, 2012-2013 and 2015, respectively). The positive rate was up to 44.6% in the epidemic year, but as low as 13.0% in the non-epidemic year.The positive rates of MP in spring, summer, autumn and winter were 21.2%(217/1 022 cases), 22.0%(230/1 044 cases), 28.9%(320/1 108 cases) and 25.1%(275/1 097 cases), respectively.There were mild epidemic peaks in April to May and August to September every year.The infection rates of MP in autumn were significantly higher than those in other 3 seasons(χ^2=16.50, 13.30, 4.07, all P<0.05). The positive rates of children in each age group were 10.6%(69/651 cases) in < 1 year old group, 17.5%(216/1 233 cases) in 1- 2 years old group, 28.5%(369/1 294 cases) in 3-6 years old group, and 35.5%(388/1 093 cases) in > 7 years old group, respectively.The positive rate of preschool and school-age children was 31.7%(757/2 387 cases), which was higher than that of the infants (15.1%, 285/1 884 cases), and there was a statistical significance (χ^2=157.0, P<0.05). The positive rate of MP in girls was 28.3%(481/1 699 cases), which was significantly higher than that in boys [21.8%(561/2 572 cases)], and there was a statistical significance (χ^2=23.4, P<0.05), especially during the epidemic years. Conclusions The detection rate of MP infection in children in Beijing is high in autumn and winter, and low in summer.The positive rate of MP increases with age.The high incidence of MP infection is in preschool and school-age children, especially girls.There is a significant difference between the prevalence of MP infection and the prevalence intervals.The prevalence of MP infection may be closely related to the long-term closed and semi-closed living habits.