Identification of Human Bocavirus type 4 in a child asymptomatic for respiratory tract infection and acute gastroenteritis – Goiânia,Goiás,Brazil

Human Bocavirus (HBoV) has been identified from feces and respiratory samples from cases of both acute gastroenteritis and respiratory illness as well as in asymptomatic individuals.The aim of this study was to detect and characterize HBoV from fecal samples collected from hospitalized children aged less than five years old with no symptoms of respiratory tract infection (RTI) or acute gastroenteritis (AGE). The study involved 119 children and one fecal sample was collected from each participant between 2014 and 2015. HBoV was detected using Nested-PCR, and the viral type identified by genomic sequencing. HBoV-4 was identified from one sample obtained from a hospitalized child with soft tissue tumor of the submandibular region. This is the first report of HBoV-4 identification in Brazil, but we consider that this type may be circulating in the country similar to the other types and new investigations are necessary.     

Epidemiological profile and clinical associations of human bocavirus and other human parvoviruses

BACKGROUND: Human bocavirus (HBoV) and PARV4 are newly discovered human parvoviruses. HBoV, which was first detected in respiratory samples, has a potential role in the development of human respiratory disease. The present study compared the frequencies, epidemiological profiles, and clinical backgrounds of HBoV and PARV4 infections with those of other respiratory virus infections, by evaluating diagnostic samples referred to the Specialist Virology Laboratory (SVL) at the Royal Infirmary of Edinburgh (Edinburgh, United Kingdom). METHODS: Anonymized samples and study subject information were obtained from the respiratory sample archive of the SVL. Samples were screened for HBoV, PARV4, B19, respiratory syncytial virus (RSV), adenoviruses, influenza viruses, and parainfluenza viruses by use of nested polymerase chain reaction. RESULTS: HBoV infection was detected in 47 (8.2%) of 574 study subjects, ranking third in prevalence behind RSV infection (15.7%) and adenovirus infection (10.3%). Peak incidences of HBoV were noted among infants and young children (age, 6-24 months) during the midwinter months (December and January) and were specifically associated with lower respiratory tract infections. HBoV infections were frequently accompanied by other respiratory viruses (frequency, 43%), and they were more prevalent among individuals infected with other respiratory viruses (17%), frequently adenovirus or RSV. All respiratory samples were negative for PARV4. CONCLUSIONS: In the present study, HBoV was a frequently detected, potential respiratory pathogen, with a prevalence and an epidemiological profile comparable to those of RSV. Identification of HBoV infections may be clinically important in the future.     

Serologically diagnosed acute human bocavirus 1 infection in childhood community‐acquired pneumonia

Aim

To assess the role of human bocavirus 1 (HBoV1) as a causative agent of non‐severe community‐acquired pneumonia (CAP) in children.

Methods

Patients aged 2‐59 months with non‐severe CAP (respiratory complaints and radiographic pulmonary infiltrate/consolidation) attending a University Hospital in Salvador, Brazil were enrolled in a prospective cohort. From 820 recruited children in a clinical trial ( ClinicalTrials.gov NCT01200706), nasopharyngeal aspirate (NPA), and acute and convalescent serum samples were obtained from 759 (92.6%) patients. NPAs were tested for 16 respiratory viruses by PCR. Acute HBoV1 infection was confirmed by measuring specific IgM and IgG responses in paired serum samples.

Results

Respiratory viruses were detected in 693 (91.3%; 95%CI: 89.1‐93.2) CAP cases by PCR. HBoV1‐DNA was detected in 159 (20.9%; 95%CI: 18.2‐24.0) cases. Of these 159 PCR positive cases, acute HBoV1 infection was confirmed serologically in 38 cases (23.9%; 95%CI: 17.8‐31.0). Overall, acute HBoV1 infection was confirmed in 5.0% (38/759) of non‐severe CAP patients. HBoV1 was detected in 151 cases with at least one other virus making 31.7% of all multiple virus (n = 477) detections. Among all 759 cases, 216 had one respiratory virus detected, and sole HBoV1 was detected in only 8 (3.7%). Acute HBoV1 infection was serologically diagnosed in 34 (22.5%) HBoV1‐DNA‐positive cases with another virus, compared to 4 (50.0%) cases with sole virus detection (p = 0.09).

Conclusion

HBoV1 was detected by PCR in one fifth of the children with non‐severe CAP and acute HBoV1 infection was serologically confirmed in one quarter of these cases.

     

广东地区首例人博卡病毒的检出及鉴定

目的 建立人博卡病毒(HBoV)筛查检测平台,了解广东地区支气管肺炎患儿HBoV感染情况.方法 采用PCR技术筛查HBoV核蛋白(NP)基因片段,阳性标本作HBoV衣壳蛋白(VP)基因片段鉴定,并进行核酸序列和进化树分析.结果 从50例住院支气管肺炎患儿鼻咽分泌物中检测出1例HBoV,为广东地区首例,命名为GD-1株.HBoV VP基因部分序列分析与基因库中HBov VP基因序列同源性比对,除与韩国KNIH-2K6GJ2713株同源性为36%、与美国NH4549株同源性为77%外,与其他所有VP基因序列同源性均>95%,与法国株、北京株、加拿大株的同源性>98%.GD-1株HBoV部分VP基因片段与北京CZ株、加拿大株、西班牙株、意大利株等在同一基因进化簇主分枝中,与法国175/03/2002FRA株同在一个侧枝中.结论 广东地区存在HBoV感染,有进一步研究的必要性.     

Human bocavirus and human metapneumovirus in hospitalized children with lower respiratory tract illness in Changsha,China

Background

Lower respiratory tract illness is a major cause of morbidity and mortality in children worldwide, however, information about the epidemiological and clinical characteristics of LRTIs caused by HMPV and HBoV in China is limited.

Objectives

Human bocavirus (HBoV) and human metapneumovirus (HMPV) are two important viruses for children with lower respiratory tract infections (LRTI). We aimed to assay the correlation between viral load and clinical characteristics of HBoV and HMPV with LRTI in Changsha, China.

Methods

Nasopharyngeal aspirates (NPAs) from children with LRTI were collected. Real‐time PCR was used to screen HBoV and HMPV. Analyses were performed using SPSS 16.0 software.

Results

Pneumonia was the most frequent diagnosis. There was no significant difference between HBoV‐ and HMPV‐positive patients in age (P = .506) or hospitalization duration (P = .280); 24.1% and 18.2% were positive for HBoV and HMPV. HBoV infections peaked in summer (32.2%), and HMPV infections peaked in winter (28.9%). The HBoV‐positive patients had a shorter hospitalization duration than the HBoV‐negative patients (P = .021), and the HMPV‐positive patients had a higher prevalence of fever than the HMPV‐negative patients (P = .002). The HBoV viral load was significantly higher among patients aged <1 year (P = .006). The mean HBoV and HMPV viral loads were not significantly different between patients with single infections and coinfections. Patients infected with HBoV only were older than those coinfected with HBoV and other respiratory viruses (P = .005). No significant difference was found in the clinical characteristics of patients infected with HMPV only and those coinfected with HMPV and other respiratory viruses.

Conclusion

Pneumonia was the most frequent diagnosis caused by HBoV and HMPV. Neither HBoV nor HMPV viral load was correlated with disease severity.     

Prevalence and Molecular Characterization of Human Bocavirus Detected in Croatian Children with Respiratory Infection

Human bocavirus (HBoV) 1 is considered an important respiratory pathogen, while the role of HBoV2-4 in clinical disease remains somewhat controversial. Since, they are characterized by a rapid evolution, worldwide surveillance of HBoVs’ genetics is necessary. This study explored the prevalence of HBoV genotypes in pediatric patients with respiratory tract infection in Croatia and studied their phylogeny. Using multiplex PCR for 15 respiratory viruses, we investigated 957 respiratory samples of children up to 18 years of age with respiratory tract infection obtained from May 2017 to March 2021 at two different hospitals in Croatia. Amplification of HBoV near-complete genome or three overlapping fragments was performed, sequenced, and their phylogenetic inferences constructed. HBoV was detected in 7.6% children with a median age of 1.36 years. Co-infection was observed in 82.2% samples. Sequencing was successfully performed on 29 HBoV positive samples, and all belonged to HBoV1. Croatian HBoV1 sequences are closely related to strains isolated worldwide, and no phylogenetic grouping based on mono- or co-infection cases or year of isolation was observed. Calculated rates of evolution for HBoV1 were 10⁻⁴ and 10⁻⁵ substitutions per site and year. Recombination was not detected among sequences from this study.     

Human bocavirus infection in hospitalized children in Italy

Background Human bocavirus (HBoV) was first discovered in Sweden in 2005 and has now been found worldwide; however its role in clinically relevant diseases has not yet been clearly defined. Objectives To gain new insight into HBoV infection among children hospitalized with acute respiratory infections in Rome. Methods Between November 2004 and May 2007, 415 nasal washings were tested for the presence of an extensive range of respiratory viruses using molecular methods. Results Viral pathogens were detected in 214 children (51·6%), 28·9% being respiratory syncytial virus (RSV) and 9·6% being rhinovirus positive. Of the 34 children (8·2%) who tested positive for HBoV, 21 (61·8%) were co‐infected with another respiratory virus, mainly RSV. Human bocavirus was the only pathogen identified in four pneumonia and six bronchiolitis cases in March 2005 and January 2007, respectively. Human bocavirus was also detected in one child hospitalized with gastroenteritis and in another with erythema. Conclusions In the examined population, HBoV was the third most common virus detected but with a high rate of co‐infection with other respiratory viruses. Human bocavirus appeared to be the etiological agent in some pneumonia and bronchiolitis cases in which tests for all likely respiratory pathogens were negative.     

人博卡病毒全基因组序列测定与种系分析

目的了解福州地区人博卡病毒(HBoV)在儿童呼吸道感染中的检出情况,并对其进行全基因组序列测定和种系分析。方法收集2007年11月至2008年10月在福建省妇幼保健院因下呼吸道感染住院的重症监护病房的57例小儿鼻咽抽取物标本,用一对特异引物通过PCR扩增法对HBoV基因片段进行检测,对检测出的2例HBoV(FZ1和FZ40)用7对全序列引物进行扩增和拼接,获得这两株病毒全基因组序列,上传GenBank并与基因库中国内外其它10株HBoV的全基因组序列和各氨基酸序列进行比对,并做种系分析。结果FZ1株基因组序列全长为5299bp,与HBoV参考株st2株序列长度相同;而FZ40株的基因组序列全长少2bp。病毒全基因组编码4种蛋白,分别是非结构蛋白NS1、核蛋白NP-1和衣壳蛋白VP1、VP2。结论种系分析显示福州的FZ40株与浙江温岭的WLL-1株关系较近,而FZ1株与北京的两株及泰国的CU6株关系较近。     

Human bocavirus infection in young children in the United States: molecular epidemiological profile and clinical characteristics of a newly emerging respiratory virus

BACKGROUND: Human bocavirus (HBoV) is a newly identified human parvovirus that was originally identified in the respiratory secretions of children with respiratory tract disease. To further investigate the epidemiological profile and clinical characteristics of HBoV infection, we screened infants and children <2 years of age (hereafter referred to as "children") for HBoV. METHODS: Children for whom respiratory specimens submitted to a diagnostic laboratory tested negative for respiratory syncytial virus, parainfluenza viruses (types 1-3), influenza A and B viruses, and adenovirus, as well as asymptomatic children, underwent screening for HBoV by use of polymerase chain reaction (PCR). Respiratory specimens were obtained from the children from 1 January 2004 through 31 December 2004. RESULTS: Twenty-two (5.2%) of the 425 children who had a respiratory specimen submitted to the diagnostic laboratory and 0 of the 96 asymptomatic children were found to be positive for HBoV by PCR (P=.02). Fever, rhinorrhea, cough, and wheezing were observed in > or =50% of the HBoV-positive children. Of the 17 children who had chest radiography performed, 12 (70.6%) had abnormal findings. HBoV appeared to have a seasonal distribution. Nucleotide polymorphisms were detected in the viral capsid protein (VP) 1/VP2 genes. Two distinct HBoV genotypes circulated during the study period. CONCLUSIONS: HBoV is circulating in the United States and is associated with both upper and lower respiratory tract disease in infants and young children.     

Human bocavirus amongst an all‐ages population hospitalised with acute lower respiratory infections in Cambodia

Please cite this paper as: Arnott et al. (2013) Human bocavirus amongst an all‐ages population hospitalised with acute lower respiratory infections in Cambodia. Influenza and Other Respiratory Viruses 7(2) 201–210. Background Human bocavirus (HBoV) is a novel parvovirus that is associated with respiratory and gastrointestinal tract disease. Objectives To investigate the prevalence and genetic diversity of HBoV amongst hospitalized patients with acute lower respiratory infection (ALRI) in Cambodia. Study Design Samples were collected from 2773 patients of all ages hospitalised with symptoms of ALRI between 2007 and 2009. All samples were screened by multiplex RT‐PCR/PCR for 18 respiratory viruses. All samples positive for HBoV were sequenced and included in this study. Results Of the samples tested, 43 (1·5%) were positive for HBoV. The incidence of HBoV did not vary between the consecutive seasons investigated, and HBoV infections were detected year‐round. The incidence of HBoV infection was highest in patients aged <2 years, with pneumonia or bronchopneumonia the most common clinical diagnosis, regardless of age. A total of 19 patients (44%) were co‐infected with HBoV and an additional respiratory pathogen. All isolates were classified as HBoV type 1 (HBoV‐1). High conservation between Cambodian NP1 and V1V2 gene sequences was observed. Conclusions Human bocavirus infection can result in serious illness, however is frequently detected in the context of viral co‐infection. Specific studies are required to further understand the true pathogenesis of HBoV in the context of severe respiratory illness.     

广东地区急性呼吸道感染儿童人类博卡病毒的流行状况

目的 了解广东地区急性呼吸道感染患儿人类博卡病毒(HBoV)的感染情况.方法 收集广东地区2007年6月至2008年5月期间呼吸道感染患儿的鼻咽分泌物447份,采用PCR法检测HBoV衣壳蛋白(VP)基因片段,阳性标本作核酸序列测定,并与基冈库中的已知序列进行序列比对和系统进化树分析.结果 447例呼吸道感染患儿标本中HBoV阳件率为5.1%.其中10例患儿与其他病毒混合感染,占阳性标本的43.5%.阳件患儿的主要临床诊断为喘息性肺炎、毛细支气管炎和支气管肺炎,年龄分布从42 d到6岁,主要集中在1岁以内,HBoV感染的季节分布偏向夏、秋及晚春.经序列比对和进化树分析.阳性株的VP基因片段与瑞典株ST1的核酸及氨基酸序列同源性分别为97.8%～98.8%及99.3%～100.0%.结论 HBoV是广东地区儿童下呼吸道感染的重要病原之一,且在1岁以内患儿中高发.该地区HBoV流行株的VP基因片段较为保守,但也存在导致氨基酸改变的突变株.     

Human bocavirus: a novel parvovirus epidemiologically associated with pneumonia requiring hospitalization in Thailand

BACKGROUND: We detected human bocavirus (HBoV) infection in 4.5% of hospitalized patients with pneumonia in rural Thailand. However, the role of HBoV as a pathogen is unclear. METHODS: We compared HBoV infection in patients with pneumonia with that in asymptomatic control patients enrolled between 1 September 2004 and 31 August 2005 in the same hospitals in Thailand. We examined outpatients with influenza-like illness for HBoV infection and tested for 13 additional respiratory viruses. Epidemiologic and clinical characteristics of HBoV infection are described. RESULTS: HBoV infection was detected in 20 (3.9%) of 512 outpatients and 3 (1%) of 280 control patients. Coinfection with other viruses was detected in 83% of patients with pneumonia and in 90% of outpatients. Compared with control patients, HBoV infection was significantly associated with pneumonia requiring hospitalization (adjusted odds ratio, 3.56 [95% confidence interval, 1.06-11.91]; P=.04). Eighty-three percent of HBoV infections were detected in patients with pneumonia who were <5 years old. More patients with pneumonia associated with HBoV-respiratory syncytial virus (RSV) or human parainfluenza virus (HPIV) coinfections had wheezing than patients with RSV and HPIV infections alone (9 [53%] of 17 vs. 32 [23%] of 138]; P=.01). CONCLUSIONS: HBoV infection was epidemiologically associated with pneumonia among young children in rural Thailand, but infection and illness may be dependent on coinfection with other viruses.     

2665例急性上呼吸道感染患儿的病原学及临床特征

目的 分析急性上呼吸道感染儿童患者的病原学及临床特征。方法 以南方医科大学珠江医院2009年11月至2015年9月收治的2 665例急性上呼吸道感染儿童为研究对象,采用qRT-PCR方法检测临床上常见的8种呼吸道病毒(流感病毒、呼吸道合胞病毒、副流感病毒、腺病毒、人类博卡病毒、人类冠状病毒、人类偏肺病毒、鼻病毒)。结果 共检测患儿标本2 665份,其中阳性标本1 566份,总阳性率为58.8%。四个季节中8种呼吸道病毒检出率存在明显差异,并以春季最高,夏冬季次之,秋季最低。儿童呼吸道病毒感染率随着年龄增加而逐渐降低,并以0~1岁婴幼儿病毒检出率最高64.5%。男童呼吸道病毒感染率高于女童,住院患儿呼吸道病毒检出率高于门诊患儿。混合感染标本260份,占阳性标本数的16.6%,主要集中于0~3岁儿童患者标本中,并因季节而异,秋冬季节较少,而春夏季节较为普遍。咳嗽为呼吸道病毒感染的主要临床症状,咳痰和流涕次之,临床症状在8种呼吸道病毒感染患儿中存在差异。结论 本调查分析了急性上呼吸道感染患儿中8种常见呼吸道病毒的病原学及临床特征,为指导临床治疗及防控提供相关数据。     

Human bocavirus - insights into a newly identified respiratory virus

Human Bocavirus (HBoV) was discovered in 2005 using a molecular virus screening technique. It is often found in respiratory samples and is a likely cause for respiratory diseases in children. HBoV is distributed worldwide and has been found not only in respiratory samples, but also in feces, urine and serum. HBoV infections are mostly found in young children and coinfections with other respiratory viruses are often found, exacerbating the efforts to link HBoV to specific symptoms. The purpose of this review is to give an overview of recent HBoV research, highlighting some recent findings.     

Human bocavirus: Current knowledge and future challenges

Human bocavirus(HBoV) is a parvovirus isolated about a decade ago and found worldwide in both respiratory samples, mainly from early life and children of 6-24 mo of age with acute respiratory infection, and in stool samples, from patients with gastroenteritis. Since then, other viruses related to the first HBoV isolate(HBoV 1), namely HBoV 2, HBoV 3 and HBoV 4, have been detected principally in human faeces. HBo Vs are small nonenveloped single-stranded DNA viruses of about 5300 nucleotides, consisting of three open reading frames encoding the first two the non-structural protein 1(NS1) and nuclear phosphoprotein(NP1) and the third the viral capsid proteins 1 and 2(VP1 and VP2). HBoV pathogenicity remains to be fully clarified mainly due to the lack of animal models for the difficulties in replicating the virus in in vitro cell cultures, and the fact that HBo V infection is frequently accompanied by at least another viral and/or bacterial respiratory and/or gastroenteric pathogen infection. Current diagnostic methods to support HBoV detection include polymerase chain reaction, real-time PCR, enzymelinked immunosorbent assay and enzyme immunoassay using recombinant VP2 or virus-like particle capsid proteins, although sequence-independent amplification techniques combined with next-generation sequencing platforms promise rapid and simultaneous detection of the pathogens in the future. This review presents the current knowledge on HBoV genotypes with emphasis on taxonomy, phylogenetic relationship and genomic analysis, biology, epidemiology, pathogenesis and diagnostic methods. The emerging discussion on HBoV s as true pathogen or innocent bystander is also emphasized.     

Respiratory Syncytial Virus Coinfections With Rhinovirus and Human Bocavirus in Hospitalized Children

It is not clearly established if coinfections are more severe than single viral respiratory infections.The aim of the study was to study and to compare simple infections and viral coinfections of respiratory syncytial virus (RSV) in hospitalized children.From September 2005 to August 2013, a prospective study was conducted on children younger than 14 years of age, admitted with respiratory infection to the Pediatric Department of the Severo Ochoa Hospital, in Spain. Specimens of nasopharyngeal aspirate were taken for virological study by using polymerase chain reaction, and clinical data were recorded. Simple RSV infections were selected and compared with double infections of RSV with rhinovirus (RV) or with human bocavirus (HBoV).In this study, 2993 episodes corresponding to 2525 children were analyzed. At least 1 virus was detected in 77% (2312) of the episodes. Single infections (599 RSV, 513 RV, and 81 HBoV) were compared with 120 RSV-RV and 60 RSV-HBoV double infections. The RSV-RV coinfections had fever (63% vs 43%; P < 0.001) and hypoxia (70% vs 43%; P < 0.001) more often than RV infections. Hypoxia was similar between single or dual infections (71%). Bronchiolitis was more frequent in the RSV simple group (P < 0.001). Pediatric intensive care unit admission was more common in RSV simple or RSV-RV groups than in the RV monoinfection (P = 0.042).Hospitalization was longer for both RSV simple group and RSV-HBoV coinfection, lasting about 1 day (4.7 vs 3.8 days; P < 0.001) longer than in simple HBoV infections. There were no differences in PICU admission. RSV single group was of a younger age than the other groups.Coinfections between RSV-RV and RSV-HBoV are frequent. Overall viral coinfections do not present greater severity, but have mixed clinical features.     

Human bocavirus infection in a neonatal intensive care unit

Human bocavirus (HBoV) plays a non-insignificant role as a pathogen in respiratory tract diseases in the pediatric population, especially in infants younger than 2 years of age. In this paper, we have described two cases of a possible nosocomial infection in a neonatal intensive care unit being HBoV the sole detected respiratory virus in clinical samples.     

乌鲁木齐地区RT-PCR法检测儿童急性呼吸道病毒的临床研究

目的利用多重荧光逆转录聚合酶链反应(RT-PCR)分析急性下呼吸道感染患儿4种病毒:人腺病毒(HADV)、人博卡病毒(HBoV)、人偏肺病毒(HMPV)、人呼吸道合胞病毒(HRSV)的感染情况。方法收集1045例急性呼吸道感染的住院患儿鼻咽深部分泌物标本,采用多重荧光RT-PCR进行呼吸道病毒4项指标检测,就病毒分布情况、季节因素等方面进行临床流行病学特点分析。结果1045例患儿中有281例4种呼吸道病毒阳性,总阳性率为26.89%;其中单一病毒感染194例(69.04%)、混合病毒感染87例(30.96%),HMPV感染最多,为120例(42.70%)、其次为HRSV感染119例(42.35%);在各年龄组中≤3岁组阳性229例(36.06%),4~7岁组阳性114例(42.22%),≥8岁组阳性63例(45.00%)。从季节分布来看,春、夏、秋、冬四季的检出率分别为25.68%、28.24%、49.34%、65.57%。结论多重荧光RT-PCR法能快速检测乌鲁木齐地区儿童急性呼吸道病毒,呼吸道病毒感染主要为HMPV和HRSV感染;呼吸道病毒患儿感染率最高年龄段为≥8岁;以秋季和冬季为呼吸道病毒感染高发期。     

上海地区643例呼吸道感染患儿鼻咽分泌物病毒病原检测分析

目的 探讨上海地区急性儿童呼吸道感染的病毒病原学特点,为临床诊断和治疗提供参考.方法 收集2012年1月至2013年12月,在上海交通大学医学院附属第九人民医院、新华医院、普陀区中心医院因急性呼吸道感染就诊的643例患儿的鼻咽抽吸物标本,采用反转录聚合酶链反应(RT-PCR)和聚合酶链反应(PCR)方法检测呼吸道相关病毒HRV、RSV、ADV、IFV (A、B型)、PIV(1～4型)、HMPV、HCoV-NL63,HCoV-HKU1、HBoV.结果 共643例患儿采集了鼻炎抽吸物标本,年龄从11d至12岁,中位年龄为12个月,男402例,女241例;共检出病毒感染阳性标本369份,总检出率57.4％ (369/643),2012年RSV检出率最高,2013年ADV检出率最高,新发现病毒中HBoV检出率最高,未检测到冠状病毒NL-63.6个月到1岁年龄段病毒的检出率最高,随年龄增长,病毒的检出率逐渐下降,病毒检出贯穿全年,诊断包括上、下呼吸道感染.结论 病毒是引起上海地区儿童呼吸道感染的主要病原,以RSV和ADV为丰.