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。     

Human metapneumovirus in patients with respiratory tract infection in Kuwait

Human metapneumovirus (hMPV) has been recognized as an important cause of respiratory tract infections in all age groups and in all geographical area. The role of hMPV in causing respiratory tract infections in Kuwait was not yet investigated. The aim of this study was to determine the prevalence of hMPV infection in Kuwait among patients with respiratory tract infection with respect to other respiratory viruses. During January–December 2009, 460 respiratory samples from 388 patients with respiratory tract infection were collected from different hospitals. They were tested for hMPV RNA by real‐time PCR, and for other respiratory viruses by conventional PCR. Out of 388 patients, 110 (28%) were positive for viral respiratory infections; 21 (5.4%) were positive for hMPV, 29 (7.5%) were positive for rhinovirus, 13 (4%) were positive for respiratory syncytial virus, and 10 (3%) were positive for adenovirus. Most (n = 19, 90.5%) of hMPV‐positive patients were admitted to the intensive care unit, 76% of them were of age 2 years and below, and 24% of age 59 years and above. All hMPV‐positive elderly patients had pneumonia while 50% of hMPV‐positive infants had bronchopneumonia. Children with hMPV/rhinovirus co‐infection (n = 3, 1%) had recurrent chest infection and frequent intensive care unit admission. The hMPV infection was mostly detected between December and May, and genotype B was more prevalent than genotype A. This is the first study demonstrating the prevalence of hMPV infection in Kuwait, and suggests that hMPV infection is prevalent in infants and elderly patients with lower respiratory tract infection. J. Med. Virol. 83:1811–1817, 2011. © 2011 Wiley‐Liss, Inc.     

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。     

人偏肺病毒感染住院儿童的临床特征及病毒基因特性分析

目的 了解急性呼吸道感染住院儿童中人偏肺病毒(hMPV)的感染情况、临床特征及人偏肺病毒基因特性.方法 对2006年2月至5月、2008年3月至4月及2008年9月至2009年2月收集的天津市儿童医院急性呼吸道感染住院儿童的310份鼻咽吸取物标本进行巢式PCR检测hMPV N基因片段,并对其中17株N基因片段进行序列测定,分析序列特征并绘制种系发生树.收集所有阳性患者的临床资料.同时采用多重PCR对N基因阳性标本进行其他常见呼吸道病毒的检测.结果 310份标本中共检出20份(6.5%)hMPV.hMPV阳性患儿的年龄中位数为15.0个月(16天～9岁),其中≤2岁患儿占90.0%(18/20).男性占60.0%(12/20).17株N基因种系发生树分析显示,11株为A2b亚型.20例hMPV阳性患儿的临床诊断均为支气管肺炎,占所有采集的肺炎患儿标本的7.1%(20/282),其临床症状以咳嗽、喘息、呼吸急促、发烧等常见.35%(7/20)需要重症监护,15%(3/20)需要吸氧治疗.平均住院时间为(11.9±4.8)d.A、B型间临床特征未见明显差别.hMPV无明显流行高峰.2例hMPV阳性患儿分别与腺病毒和鼻病毒混合感染.结论 hMPV可引起婴幼儿肺炎等严重疾病.天津地区流行的hMPV以A2b为优势流行型.     

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.     

Prevailing genotype distribution and characteristics of human respiratory syncytial virus in northeastern China

Although human respiratory syncytial virus (RSV) is one of the most common viruses inducing respiratory tract infections in young children and the elderly, the genotype distribution and characteristics of RSV in northeastern China have not been investigated. Here, we identified 25 RSV‐A and 8 RSV‐B strains from 80 samples of patients with respiratory infections between February 2015 and May 2015. All 25 RSV‐A viruses were classified as the ON1 genotype, which rapidly spread and became the dominant genotype in the world since being identified in Ontario (Canada) in December 2010. All eight RSV‐B viruses belonged to the BA genotype with a 60‐nucleotide duplication, seven of which formed two new genotypes, BA‐CCA and BA‐CCB. The remaining RSV‐B virus clustered with one of the Hangzhou strains belonging to genotype BA11. Construction of a phylogenetic tree and amino acid substitution analysis showed that Changchun ON1 viruses exclusively constituted Lineages 3, 5 and 6, and contained several unique and newly identified amino acid substitutions, including E224G, R244K, L289I, Y297H, and L298P. Selective pressure was also evaluated, and various N and O‐glycosylation sites were predicted. This study provides the first genetic analysis of RSV in northeastern China and may facilitate a better understanding of the evolution of this virus locally and globally. J. Med. Virol. 89:222–233, 2017 . © 2016 The Authors. Journal of Medical Virology Published by Wiley Periodicals, Inc.

     

Co-circulation of genetically distinct human metapneumovirus and human bocavirus strains in young children with respiratory tract infections in Italy

The discovery of human Metapneumovirus (hMPV) and human Bocavirus (hBoV) identified the etiological causes of several cases of acute respiratory tract infections in children. This report describes the molecular epidemiology of hMPV and hBoV infections observed following viral surveillance of children hospitalized for acute respiratory tract infections in Milan, Italy. Pharyngeal swabs were collected from 240 children ≤3 years of age (130 males, 110 females; median age, 5.0 months; IQR, 2.0-12.5 months) and tested for respiratory viruses, including hMPV and hBoV, by molecular methods. hMPV-RNA and hBoV-DNA positive samples were characterized molecularly and a phylogenetical analysis was performed. PCR analysis identified 131/240 (54.6%) samples positive for at least one virus. The frequency of hMPV and hBoV infections was similar (8.3% and 12.1%, respectively). Both infections were associated with lower respiratory tract infections: hMPV was present as a single infectious agent in 7.2% of children with bronchiolitis, hBoV was associated with 18.5% of pediatric pneumonias and identified frequently as a single etiological agent. Genetically distinct hMPV and hBoV strains were identified in children examined with respiratory tract infections. Phylogenetic analysis showed an increased prevalence of hMPV genotype A (A2b sublineage) compared to genotype B (80% vs. 20%, respectively) and of the hBoV genotype St2 compared to genotype St1 (71.4% vs. 28.6%, respectively). Interestingly, a shift in hMPV infections resulting from A2 strains has been observed in recent years. In addition, the occurrence of recombination events between two hBoV strains with a breakpoint located in the VP1/VP2 region was identified.     

Clinical impact of human metapneumovirus genotypes and genotype-specific seroprevalence in Yamagata, Japan

The clinical impact of human metapneumovirus (hMPV) genotypes and the relation between the hMPV genotype in circulation and genotype-specific seroprevalence are yet to be clarified. We determined the genotypes of 93 hMPV strains that were isolated between 2004 and 2006 in Yamagata, Japan, and identified 35 genotype A2, 14 genotype B1, and 44 genotype B2 isolates. Children infected with genotype A2 hMPV were significantly older than those infected with genotype B1 hMPV. Diagnosis of laryngitis was more common in children with genotype B1 hMPV infection and wheezing was more prevalent in children with genotype B1 and B2 hMPV infection than in those with genotype A2 hMPV infection. We then examined genotype-specific seroprevalence by neutralization assay. The higher seropositive rate for the B2 genotype among the children aged 1-2 years is likely to reflect the outbreak of B2 genotype strains in the previous year in this community. The low seropositive rate for the B1 genotype among children aged 1-2 years appears to be associated with a finding that more than 70% of children infected with the B1 genotype were less than 3 years old. In conclusion, we found that the different clinical characteristics of hMPV infection may be associated with hMPV genotype, and the predominant genotype during a season and the affecting age may be closely related to genotype-specific immune status within a community.     

Phylogenetic analysis of human metapneumovirus from New York State patients during February through April 2010

Background

Human metapneumovirus (hMPV) is the second leading cause of lower respiratory infection (LRI) in children around the world and has been linked to LRI in multiple studies. Currently, hMPV is classified into 2 major subtypes (A and B), each with 2 subgroups (1 and 2).

Objective

To determine which hMPV genotypes were present in NYS patients with influenza-like illness (ILI) from February through April 2010, during a period of unusually heightened activity.

Study design

Specimens were collected from February through April of 2010 from patients presenting with ILI who were previously confirmed as positive for hMPV by real-time RT-PCR. A 700 base pair region of the hMPV fusion (F) gene was amplified, sequenced and resulting sequences aligned. A phylogenic tree was constructed based on prototype strains, and the partial F gene sequences obtained in this study.

Results

Bi-directional sequence was obtained from 30 patient samples and included in the phylogenic analysis. Specimen sequences grouped into hMPV genotype A2a (16), A2b (9), B2 (4) and B1 (1). No A1 genotypes were found.

Conclusion

Previously, reports have demonstrated that genotypes A1, A2, B1 and B2 circulate every season, usually with one dominant strain. In contrast, late in the 2009-2010 respiratory season, 4 of the 5 recognized genotypes of hMPV were isolated from NYS ILI patients, and by sequencing a larger portion of the fusion gene, we were able to identify the A2a and A2b genotypes.     

Genotype variability of human metapneumovirus, South Korea

Human metapneumovirus (hMPV), a virus causing lower respiratory tract infections in children, is classified two major groups or genotypes of hMPV and recently existence of multiple lineages has been suggested. The purpose of this study was to examine the extent of genetic variation and circulation pattern of hMPV in Korea. Between January 2005 and April 2007, nasopharyngeal aspirates were collected from 1,214 children <16 years of age hospitalized with acute respiratory tract infection at Sanggyepaik Hospital. Nasopharyngeal aspirates were tested for common respiratory pathogens using immunofluorescence or multiplex RT-PCR. RT-PCR was used to detect hMPV. The PCR products were purified and subsequently sequenced directly on both strands. hMPV was detected in 8.4% (102/1,214) of nasopharyngeal aspirates from children with acute respiratory tract infection. The 102 hMPV strains detected in this study were classified into two distinct F lineages, 87 strains belonged to genogroup A2 (A2a in 42, A2b in 45) and 15 strains to genogroup B. All hMPV subtypes except A1 co-circulated in Korean population. Although alternating predominance of hMPV subtypes from year to year could not be found, the changing predominance of sublineage A2a and A2b was demonstrated.     

A review on epidemiology and impact of human metapneumovirus infections in children using TIAB search strategy on PubMed and PubMed Central articles

Acute respiratory tract infections (ARTI) contribute to morbidity and mortality in children globally. Viruses including human metapneumovirus (hMPV) account for most ARTIs. The virus causes upper and lower respiratory tract infections mostly in young children and contributes to hospitalization of individuals with asthma,chronic obstructive pulmonary diseases and cancer. Moreover, hMPV pauses a considerable socio‐economic impact creating a substantial disease burden wherever it has been studied, although hMPV testing is relatively new in many countries. We aimed to comprehensively analyze the epidemiological aspects including prevalence, disease burden and seasonality of hMPV infections in children in the world. We acquired published data extracted from PubMed and PubMed Central articles using the title and abstract (TIAB)search strategy for the major key words on hMPV infections from 9/54 African, 11/35 American, 20/50 Asian, 2/14 Australian/Oceanian and 20/51 European countries. According to the findings of this review, the prevalence of hMPV infection ranges from 1.1 to 86% in children of less than 5 years of age globally. Presence of many hMPV genotypes (A1, A2, B1, B2) and sub‐genotypes (A2a, A2b, A2c, B2a, B2b) suggests a rapid evolution of the virus with limited influence by time and geography. hMPV infection mostly affects children between 2 to 5 years of age. The virus is active throughout the year in the tropics and epidemics occur during the winter and spring in temperate climates, contributing to a substantial disease burden globally.     

The role of influenza,RSV and other common respiratory viruses in severe acute respiratory infections and influenza-like illness in a population with a high HIV sero-prevalence,South Africa 2012–2015

BackgroundViruses detected in patients with acute respiratory infections may be the cause of illness or asymptomatic shedding.ObjectiveTo estimate the attributable fraction (AF) and the detection rate attributable to illness for each of the different respiratory virusesStudy designWe compared the prevalence of 10 common respiratory viruses (influenza A and B viruses, parainfluenza virus 1–3; respiratory syncytial virus (RSV); adenovirus, rhinovirus, human metapneumovirus (hMPV) and enterovirus) in both HIV positive and negative patients hospitalized with severe acute respiratory illness (SARI), outpatients with influenza-like illness (ILI), and control subjects who did not report any febrile, respiratory or gastrointestinal illness during 2012–2015 in South Africa.ResultsWe enrolled 1959 SARI, 3784 ILI and 1793 controls with a HIV sero-prevalence of 26%, 30% and 43%, respectively. Influenza virus (AF: 86.3%; 95%CI: 77.7–91.6%), hMPV (AF: 85.6%; 95%CI: 72.0–92.6%), and RSV (AF: 83.7%; 95%CI: 77.5–88.2%) infections were associated with severe disease., while rhinovirus (AF: 46.9%; 95%CI: 37.6–56.5%) and adenovirus (AF: 36.4%; 95%CI: 20.6–49.0%) were only moderately associated.ConclusionsInfluenza, RSV and hMPV can be considered pathogens if detected in ILI and SARI while rhinovirus and adenovirus were commonly identified in controls suggesting that they may cause only a proportion of clinical disease observed in positive patients. Nonetheless, they may be important contributors to disease.