南京地区儿童人偏肺病毒感染的流行病学及临床特征分析

目的了解南京地区儿童人偏肺病毒（hMPV）感染的流行病学特点及临床特征。方法收集2009年8月至2010年7月南京医科大学附属南京儿童医院住院及门诊呼吸道感染患儿的鼻咽抽吸物（NPA）及咽拭子（NPS）共642例,采用逆转录聚合酶链反应法（RT—PCR）检测hMPVM基因,将阳性PCR扩增产物进行测序、同源性和进化分析。结果642例标本中共检出hMPV阳性扩增产物35份,检出率为5．5％。系统进化分析显示南京地区hMPVB1型占51．4％,A2b型占31．4％。hMPV的发病高峰在4月份。其致呼吸道感染以1岁以内多见（71．4％）。35例hMPV感染患儿中有15例（42．8％）存在混合感染,其中与HRV的混合感染检出率最高。临床诊断以肺炎（17例,48．6％）最为常见。结论人偏肺病毒是南京地区儿童急性呼吸道感染的重要病原之一,该年度其优势流行型别为B1型,南京地区A、B两型hMPV感染患儿临床特征无明显差异。     

2007—2011年长沙地区急性下呼吸道感染住院儿童人偏肺病毒的流行状况

目的了解人偏肺病毒（hMPV）在长沙地区急性下呼吸道感染住院患儿中的流行病学特点。方法收集2007年9月至2011年2月因急性下呼吸道感染在湖南省人民医院儿科医学中心住院儿童的鼻咽抽吸物（nasopharyngealaspirates,NPA）样本2613份,采用逆转录聚合酶链反应法（RT—PCR）检测hMPVM基因,将阳性PCR扩增产物测序并与GenBank中已知的hMPV参考株进行比对、分析。结果2613份标本中hMPV阳性检出数135例,检出率为5．2％,男女之间的检出率比较有统计学差异（x2=8．007,P=0．003）,hMPV阳性检出患儿的年龄以1岁以内多见（63．2％）。hMPV阳性检出率在春季呈现高峰,从检出季节分布显示A2b型主要在冬春季节流行,而B2型主要在春夏季流行。135例hMPV长沙株分为A型和B型两个主要的基因型,其中A2b亚型在2007--2008年为优势流行型别,2009--2010年A2b和B2型共同流行,B2亚型在2011年呈优势流行型别。135例hMPV检出阳性患儿中有66例（48．9％）存在混合病毒感染,其中与HBoV混合检出率最高。结论长沙地区部分儿童的急性下呼吸道感染与hMPV有关,且阳性检出患儿年龄主要集中在1岁以下,男多于女,主要流行季节在春季,A2b型和B2型优势基因型在长沙地区共同流行,与其他病毒混合检出率较高。     

多重PCR检测儿童呼吸道感染常见病毒

目的 对深圳、粤东地区儿童呼吸道病毒感染进行监测、分析,探讨其流行规律.方法 2006年6月-2008年6月,于汕头大学附属医院、深圳市第四人民医院、揭阳市人民医院采集毛细支气管炎、支气管肺炎、喘息支气管炎等的患儿咽拭子或鼻咽分泌物标本686份,多重PCR进行9种呼吸道病毒检测.结果 在686例标本中病毒阳性362例(52.77%),其中呼吸道感染患儿中呼吸道合胞病毒(RSV)感染占首位,达到31.22%(113/362),其次是鼻病毒(RHV)为16.85%(61/362),最低是流感病毒B型(IVB)占0.83%(3/362),流感病毒A型(IVA)占14.36%(52/362),副流感病毒1型(PIV1)和副流感病毒3型(PIV3)分别占7.73%(28/362)和8.29%(30/362),腺病毒(AdV)达到9.67%(35/362),而人博卡病毒(hBOV)和人偏肺病毒(hMPV)分别占6.08%(22/362)和4.97%(18/362).结论 RSV、RHV及IVA是华南地区儿童呼吸道感染的主要病毒病原,混合感染以RSV、IVA联合其他病毒感染为主,诊治时应根据所感染病原体制定有针对性的措施.     

中国湖南地区人偏肺病毒的基因分型及其膜蛋白G基因特征的分析

目的 研究中国湖南地区人偏肺病毒(hMPV)的基因分型及其膜蛋白G序列的遗传学特征,比较分析其区域性流行特点.方法收集2005年中国湖南地区232份住院儿童鼻咽抽吸物(NPA)样本进行常见呼吸道病毒筛查,并扩增hMPV阳性样本的膜蛋白G全序列,与GenBank中已知hMPV参考株及其他地区公布的相关资料进行比对、进化等分子遗传学特征分析.结果从232份临床样本中共检测得到17份(7.3%)hMPV阳性样本,与其他病毒混合感染率达35%.扩增出其中13份hMPV样本的G蛋白全序列,分属于4种亚型(A1、A2、B1、B2).核酸长度类型有4种(711,675,660,696nt),N-连接糖基化位点数目和位置、半胱氨酸残基数目等特征与已报道的同期北京地区、日本、北美等地区hMPV调查分析结果不尽一致.结论中国湖南地区与其他地区同期hMPV调查分析结果各有特点,反映出hMPV变异显著,具有明显的地区流行特征.     

上海地区儿童下呼吸道人类偏肺病毒感染的初步研究

目的 了解人类偏肺病毒（hMPV）在上海地区儿童下呼吸道感染中的致病情况。方法 采集2004年8月-2005年1月秋冬季节我院479例因社区获得性急性下呼吸道感染（CALRTIs）住院儿童的呼吸道分泌物标本，对直接免疫荧光法常规检测病毒阴性的259份标本用逆转录．多聚酶链反应法（RT-PCR）检测hMPVM基因。对PCR阳性产物随机挑选23份直接作核苷酸序列测定，用DNAStar软件对基因序列分析。结果 259份标本中hMPV检测阳性例数为59例（22．8％），占总例数的12．3％。冬季检测阳性率明显高于秋季（31．3％vs7．5％，P〈0．01）。5岁及以下儿童53例（89．8％），5岁以上儿童6例（10．2％）。23份hMPV阳性标本目标基因部分核苷酸序列与GenBank中公布的hMPVM基因同源性达82．8％～100％，部分氨基酸序列同源性为93．0％～100％，对核苷酸序列作基因进化树分析显示存在2种不同的基因型，以Bj1816组为代表的基因型14株，以Bj1887组为代表的基因型9株。结论hMPV是上海地区儿童CALRTIs的重要致病原，上海地区儿童感染的hMPV同时存在2种不同的基因型。     

我国急性呼吸道感染患儿中检测到KI和WU多瘤病毒

目的 了解多瘤病毒WU和KI在我国儿童急性呼吸道疾病中的感染情况.方法 采用PCR扩增的方法对2006年11月至2007年10月收集的急性呼吸道感染患儿的318份鼻咽抽吸物(NPA)标本进行了多瘤病毒WU和KI基因检测.结果 318份标本共检测出14份病毒核酸阳性标本,其中WUV 7份(2.2%),KIPyV 7份(2.2%).该14例基因检测阳性患儿临床均有上呼吸道感染或下呼吸道感染症状.结论 WUV和KIPyV可能也是儿童急性呼吸道感染中较为重要的一个病原,且与儿童上呼吸道感染和下呼吸道感染存在相关性.     

重庆地区急性呼吸道感染患儿呼吸道合胞病毒流行特征及其G基因序列分析

目的 分析重庆地区2008-2009年度急性呼吸道感染住院患儿呼吸道合胞病毒(respiratory syncytial virus,RSV)的亚型流行情况,并了解优势流行株BA株的G蛋白基因特征.方法 采集2008年4月-2009年3月全年于重庆医科大学附属儿童医院因急性呼吸道感染住院的508例患儿鼻咽深部分泌物,用RT-PCR方法检测RSV并进行亚型鉴定,选取29例B亚型和10例A亚型RSV阳性标本,用RT-PCR的方法扩增全长G蛋白并测序.结果 在508例标本中,RSV阳性126例(24.8%),其中检测出A亚型43例(34.1%),B亚型80例(63.5%),A、B亚型混合感染3例(2.4%).所测的10株A亚型的G基因与标准株A2的核苷酸同源性为91.4%～92.0%,均属GA2基因型;29株B亚型的G基因与标准株CH18537的核苷酸同源性为92.0%～93.0%,其中19株均为具有60个高度重复核苷酸插入的BA株.B亚型流行株与CH18537标准株相比,G基因有多种核苷酸变异如缺失、插入等,尤其在G蛋白近C端1/3处的高变区.结论 2008-2009年RSV仍是重庆地区儿童急性呼吸道感染的主要病原,与既往两年A亚型优势流行不同,2008-2009年度B亚型毒株流行占优;近年新发现的BA株可能已成为本地区优势流行株,BA株G基因变异是否导致G蛋白功能增强,进而促进其优势流行尚有待研究.     

多重核酸检测在儿童下呼吸道感染病原学诊断中的应用分析

目的对临床诊断为下呼吸道感染(支气管肺炎、大叶性肺炎、支气管炎、毛细支气管炎)的住院患儿采集深部痰液进行细菌培养及咽拭子进行多重RT-PCR和毛细电泳联用技术,检测呼吸道常见病原(呼吸道合胞病毒、甲型流感病毒、乙型流感病毒、副流感病毒、鼻病毒、偏肺病毒、冠状病毒和腺病毒、博卡病毒、肺炎支原体、衣原体),分析多重PCR检测技术在儿童下呼吸道感染病原学诊断的临床应用价值。方法收集2018年12月至2019年2月在成都儿童专科医院住院的155例下呼吸道感染患儿的鼻咽分泌物及深部痰液标本,年龄在1月～14岁,病程在1～60天。结果本组患者男93例(60%),女62例(40%),平均发病时间为7.2天,≤7天94例,7天61例,1岁组39例(25.2%),1～3岁组42例(27.1%),3～5岁组41例(26.5%),5岁33例(21.3%),平均年龄3.1岁。多重核酸检测结果发现,155例患儿的鼻咽分泌物标本中至少有一种病原检测阳性的共计143份标本(占92.3%),其中有40份标本(占27.97%)检测到两种或两种以上病原。排名前三位的病原依次为、呼吸道合胞病毒、甲型流感病毒和偏肺病毒。按照不同年龄组病原阳性率分析,除呼吸道合胞病毒外(χ2=29.241,P0.001),其余病毒组间差异无统计学意义。通过多重PCR检查阳性标本中混合细菌感染者占57例共计59株(36.77%),各年龄组混合感染差异无统计学意义,其中卡他布兰汉菌28株(47.46%),流感嗜血杆菌18株(30.51%),肺炎链球菌9株(15.25%),金黄色葡萄球菌3株(5.08%),大肠埃希菌1株(1.70%);根据发病时间分为≤7天和7天组,核酸检测阳性结果≤7天组91例(58.71%),与7天组阳性例数52例(33.54%)(χ2=5.4,P=0.020.05)差异具有统计学意义。结论呼吸道合胞病毒是本院冬春季3岁以下儿童下呼吸道感染主要病原,偏肺病毒、流感病毒是5岁以下儿童该时期下呼吸道感染的主要病原,支原体感染仍多见于5岁以上儿童;和痰培养比较,进行多重PCR病原检测有助于全面了解儿童下呼吸道感染的病原,发病早期(≤7天)检测阳性率更高。     

长沙地区呼吸道感染儿童Saffold心肌炎病毒的调查

目的了解长沙地区Saffold病毒（以下简称为SAFV）在儿童呼吸道感染中的流行情况,探讨其与儿童呼吸道感染的相关性。方法选取湖南省人民医院儿科医学中心2007年11月至2008年10月间643名因呼吸道感染住院儿童的鼻咽抽吸物。采用实时荧光定量聚合酶链式反应（Realtime．PCR）方法扩增SAFV的5UTR的基因片段,并且统计分析临床资料。结果643份样本中共检测出SAFV阳性67份,阳性检出率为10．42％（67／643）,5岁以上未检测出该病毒。31例患迁延性肺炎和慢性肺炎的患儿标本检出SAFV8例（25．81％）,差异有统计学意义。结论本研究表明长沙地区下呼吸道感染住院儿童存在SAFV感染;SAFV可能与下呼吸道感染及病程迁延相关。     

长沙地区住院儿童人冠状病毒NL63的感染状况及临床特征

目的 了解HCOV-NL63在长沙地区急性下呼吸道感染住院儿童中的流行状况以及临床特征.方法 采集长沙地区2008年9月至2010年10月因急性下呼吸道感染住院儿童NPA样本1185份,用RT-PCR方法检测HCOV-NL63N基因,阳性扩增产物经测序确认,统计分析临床资料.结果 1185份NPA样本中,HCOV-NL63检出阳性10份,检出率为0.8％,其中春季检出1例、夏季检出6例、秋季检出2例、冬季检出1例;阳性检出病例患儿年龄最大2岁半,最小2个月,平均月龄12.5个月;男童7例,女童3例;临床诊断为支气管肺炎6例、毛细支气管炎3例、急性喉气管支气管炎1例;10例中有4例病情危重;4例有基础疾病;7例合并其他病毒混合感染;阳性扩增产物经测序分析与HCOV-NL63参考株同源性为97％～100％.结论 本资料HCOV-NL63阳性检出患儿年龄均在3岁以下;夏季检出率高;男童感染为主;单一基因型在长沙地区流行;HCOV-NL63可能也是我国儿童急性下呼吸道感染中的一种病原.     

Prevalence of human metapneumovirus in hospitalized children with respiratory tract infections in Tianjin,China

Human metapneumovirus (hMPV) has recently been recognized as an important respiratory pathogen, especially in children. At present, our understanding of the characteristics of hMPV from China is very limited. Nasopharyngeal aspirates were taken from 310 hospitalized pediatric patients. Twenty (6.5%) of them were infected with hMPV, and they all developed pneumonia. Sixty five percent (13/20) of the cases were under 12 months. Phylogenetic analysis of F gene fragments indicated that three sub-genotypes of hMPV(A2a/A2b, B1,B2) circulated in Tianjin and A2b was the predominant subtype. The Vero-E6 cell line was better than LLC-MK2 for hMPV isolation. Three hMPV strains were successfully isolated using the Vero-E6 cell line.     

Characterization of human metapneumovirus infections in Israel

Respiratory tract infections are a leading cause of morbidity and mortality worldwide. Even with the advancement of diagnostic tools, the causative agent of 20 to 30% of upper respiratory tract infections go undiagnosed. Recently, a newly identified human respiratory virus, human metapneumovirus (hMPV), was discovered in young children in The Netherlands. To study the prevalence of hMPV infections in Israeli children, respiratory specimens from 388 hospitalized children less than 5 years of age were evaluated for the presence of hMPV RNA, which was present in 42 (10.8%) of these samples. All hMPV-positive samples were negative for respiratory syncytial virus (RSV), influenza viruses (Flu) A and B, adenovirus, and parainfluenza viruses 1, 2, and 3. Conversely, hMPV RNA was not detected in 76 RSV-positive and 38 Flu A- or B-positive samples. Most hMPV activity was between the months February and April. Sequence analysis of 20 positive samples revealed that both of the hMPV genotypes (groups 1 and 2) have circulated in central Israel during the study period. Moreover, three of the four known hMPV subgroups (1A, 1B, and 2B) were detected among the tested samples. Seroprevalence of hMPV in 204 patients from the central part of Israel revealed that 100% of the children are hMPV seropositive by the age of 5 years old. We conclude that hMPV is a common respiratory pathogen in Israel, while mixed infections of hMPV with RSV or Flu in hospitalized children are apparently rare.     

Epidemiological and clinical features of hMPV, RSV and RVs infections in young children.

BACKGROUND: Human metapneumovirus (hMPV) has recently been isolated from children with acute respiratory tract infections (RTIs). The epidemiological and clinical characteristics of hMPV infection need further investigation. OBJECTIVES: The purpose of this study was to compare the clinical features of hMPV, respiratory syncytial virus (RSV) and rhinoviruses (RV) infections in children less than 3 years of age presenting to an emergency department with acute respiratory illness. STUDY DESIGN: From December 2002 to April 2004, all children under age three (n=931) admitted for acute respiratory illness to Dijon Hospital, France, were investigated for respiratory viruses in nasal washes. RESULTS: hMPV was detected in 6% of children (in 10.1% (n=38) the first winter and in 3.3% (n=17) the second winter); RSV was detected in 28.5% of the children, while rhinoviruses were found in 18.3%. Five hMPV-infected children had evidence of dual infection, two with RSV and three others with RV. The median age of the patients with hMPV infection was 6 months, and the main clinical symptoms were rhinorrhea (74.5%) and cough (67%). A lower tract disease occurred in 66% of hMPV-positive patients. Gene sequencing of hMPV isolates revealed co-circulation of the two major groups of hMPV during the study period; no difference in pathogenicity was found. There was no difference in the prevalence of bronchiolitis where hMPV, RSV or rhinoviruses were present. Asthma was found more often in hospitalized children with hMPV and rhinoviruses than among those with RSV (p<0.001). CONCLUSIONS: These results provide further evidence of the importance of hMPV as a pathogen associated with respiratory tract infection in children.     

Co-circulating genetically divergent A2 human metapneumovirus strains among children in southern Taiwan

An outbreak of human metapneumovirus (hMPV) among children in southern Taiwan in 2004 prompted the investigation of the molecular epidemiology of hMPV from September 2003 to August 2005. Respiratory specimens that were culture negative for a panel of respiratory viruses were examined for the presence of hMPV by RT-PCR. The results indicated that 59 out of 546 (10.8%) children were hMPV-positive. The majority of these hMPV-positive children were less than 2 years old (59.4%), females (61%), and inpatients (67.8%). Infections occurred throughout the year, but peaked during the spring and/or summer months. Sequence analysis of the fusion gene from the isolates revealed two phylogenetic groups with five possible lineages (A1, A2a/A2b, B1, and B2). Among these co-circulating strains, A2 strains were most frequently observed and demonstrated the greatest divergence. Deduced amino acid sequence analysis identified several variant amino acids specific to the A2 lineage. Lineage-specific amino acid substitutions were noted at aa233, aa286, aa312, aa348, and aa296. This study indicated that genetically divergent strains of hMPV which caused respiratory disease and hospitalization were circulating among children in Taiwan.     

Usefulness of two new methods for diagnosing metapneumovirus infections in children

Human metapneumovirus (hMPV) is associated with acute respiratory tract infections, mainly in paediatric patients. The aim of this study was to evaluate the usefulness of two new commercial techniques available for the detection of hMPV in clinical samples from children: an enzyme immunoassay, hMPV EIA (Biotrin International Ltd), and a molecular assay, real-time RT-PCR (Pro hMPV Real Time Assay Kit; Prodesse). A total of 184 nasopharyngeal aspirate specimens from 173 children aged less than 5 years who were hospitalized with acute wheezing were analysed. Respiratory syncytial virus was detected in 27% of the samples, followed by influenza A virus (6%), parainfluenza virus (PIV)3 (2.2%), adenovirus (2%), PIV1 (1.1%), PIV2 (1.1%), and influenza B virus (0.5%). The presence of hMPV was tested in all samples, using the real-time RT-PCR and EIA. Real-time RT-PCR detected 13 hMPV-positive samples (8%), and EIA detected 17 (9.3%). When the EIA results were compared with those of real-time RT-PCR for the detection of hMPV, a good correlation was found (94%). A relatively low co-infection rate (15%) was observed in our patients. RT-PCR and EIA provide robust methods for the diagnosis of hMPV infection in children.