2000年冬-2006年春北京地区急性呼吸道感染患儿中呼吸道合胞病毒的监测

Surveillance for respiratory syncytial virus subtypes A and B in children with acute respiratory infections in Beijing during 2000 to 2006 seasons

目的对北京急性呼吸道感染患儿进行呼吸道合胞病毒(RSV)的监测并进行亚型分析,探讨其流行规律。方法2000年11月-2006年3月,于首都儿科研究所附属儿童医院采集因急性呼吸道感染就诊的门诊及住院的患儿咽拭子或鼻咽分泌物标本10048份,接种于Hep-2细胞进行病毒分离,同时用免疫荧光法对鼻咽分泌物标本进行呼吸道病毒抗原的快速检测,对部分RSV阳性的标本用RT-PCR进行了亚型鉴定。结果(1)在10048份标本中,有2286份为RSV阳性,阳性检出率为22·8%。其中病房标本7176份,RSV阳性2153份,阳性检出率为30·0%;门诊标本2872份,RSV阳性133份,阳性检出率为4·6%。(2)2000-2001年冬春、2002-2003年冬春、2004-2005年冬春RSV的阳性检出率分别为14·0%、18·2%和20·4%,而2001-2002年冬春、2003-2004年冬春和2005-2006年冬春RSV的阳性检出率分别为42·3%、41·0%和40·5%。(3)对938份RSV阳性标本的亚型监测结果:A亚型691份,占73·7%,B亚型247份,占26·3%,2000-2001、2004-2005年冬春季RSV感染以B亚型为主;而2001-2002、2002-2003、2003-2004年冬春季以A亚型为主;2005-2006年为A、B亚型同时流行。结论RSV是冬春季婴幼儿下呼吸道感染的主要病毒病原,RSV呈现出隔年高峰的流行趋势,RSVA、B亚型是交替出现的,并且有时以相近的比例同时出现。

Objective To characterize the prevalence and occurrence of subgroups of human respiratory syncytial virus （RSV） in infants and young children with acute respiratory infections （ARI） in Beijing area. Methods RSVs were identified from nasopharyngeal aspirates and throat swabs collected from infants and children with ARI who visited the Children＇s Hospital Affiliated to Capital Institute of Pediatrics during the period of November 2000 to March 2006, by virus isolation in Hep-2 cells and antigen detection by indirect immunofluorescence assay （IFA）. RT-PCR was used to differentiate subgroups A and B of RSV from part of the positive specimens. Results Out of 10 048 specimens including 7176 nasopharyngeal aspirates from inpatients and 2872 throat swabs from outpatients, 2286 （ 22. 8% ） were RSV positive. The positive rate for RSV identification were 30. 0% （2153/7176） in specimens from the hospitalized patients, which was higher than that from outpatients （4. 6%, 133/2872）. The youngest of the RSV positive patients was 1 day after birth and the oldest was 15 years of age, with 73.0% younger than 1 year. Among those RSV positives, only 1.6% were older than 5 years. The ratio of male to female who were RSV positive was 2. 4：1 （1598： 674）. The clinical diagnosis for 91.2% （1991） of those RSV positive patients was severe lower respiratory infections including bronchiolitis and pneumonia, whereas in only 8. 8% （192） the diagnosis was upper respiratory infections. The data revealed that RSV started to be detected in October each year during the survey period and November to next April was the RSV season. The detection rate declined in May and almost no RSV could be found in summer. Positive rates for RSV detection were 42.3%, 41.0% and 40. 5% in the seasons of 2001 - 2002, 2003 - 2004, 2005 - 2006, which were higher than those in seasons of 2000 - 2001 （ 14. 0% ）, 2002 - 2003 （ 18. 2 % ）, 2004 - 2005 （20. 4% ）. Subtyping of A and B during the surveillance period showed that 73.7% （691/938） were subgroup A and 26. 3% （247/938） were subgroup B. Subgroup B was predominant in the 2000 -2001 and 2004 -2005 seasons, whereas subgroup A predominated in the 2001 - 2002, 2002 - 2003 and 2003 - 2004 seasons. Almost equal proportions of subgroup A and B appeared in 2005 -2006 seasons. Conclusion The data indicate that RSV is an important etiological agent for lower respiratory infections in infants and young children in winter and spring during the survey period. The pattern of RSV circulation varied alternately with higher rate every other year. The predominant subgroup changed between A and B, and co-circulated in equal proportion in some years.