Human bocavirus ; genetics ; isolation & purification ; metabolism ; pathogenicity ; Humans ; Neonatology ; Research Report

Human bocavirus 1 (HBoV1) is a novel virus that mainly causes respiratory tract infection, and it has the characteristic of genome of Parvovirus, containing three open reading frames that encode non-structural proteins NS1 and NP1 and structural proteins VP1 and VP2. Circular episome is present during the rolling circle replication of HBoV1, which provides the possibility of full genome amplification and infectious clone construction to save HBoV1. The recombination between HBoV1 and HBoV2-4 occurs frequently. With the three-dimensional culture, in vitro culture of HBoV1 provides a powerful tool for research on the pathogenesis of HBoV1. This review focuses on the molecular characteristics, association with diseases, in vitro culture, diagnosis and treatment of HBoV1.
Diarrhea ; virology ; Genomics ; Human bocavirus ; genetics ; isolation & purification ; physiology ; Humans ; Meningitis ; virology ; Respiratory Tract Diseases ; virology

Gastroenteritis ; etiology ; virology ; Human bocavirus ; isolation & purification ; Humans ; Parvoviridae Infections ; diagnosis ; Respiratory Tract Diseases ; etiology ; virology

Human bocavirus 1 (HBoV1) non-structural protein NS1 is a multifunctional protein important for virus replication and induction of apoptosis in host cell. To better understand the function of the NS1 protein, it is urgent to address reducing the toxicity of NS1 to host cells. In the present study, we established a stable cell line that regulates expression of NS1 of HBoV1. The recombinant lentivirus plasmid containing a regulatable promoter fused with ns1 gene was constructed and transfected into HEK 293T cells using transfection reagent. The HEK 293T cell lines stably expressing NS1-100 and NS1-70 proteins were established by screening resistant cells with puromycin and inducing NS1 expression with doxycycline. The expression of NS1 protein was determined by fluorescent labeling protein and Western blotting. HBoV1 promoter was transfected into stably expressing NS1 cell line and its trans-transcriptional activity was analyzed. The results showed that NS1 protein was expressed stably in the established cell lines and had a strong activation activity on the HBoV1 promoter driving luciferase gene. Taken together, this study provides a solid basis for further research on the function of NS1 and the pathogenesis of human bocavirus.
Human bocavirus ; Promoter Regions, Genetic ; Transcriptional Activation ; Viral Nonstructural Proteins ; Virus Replication

Human bocavirus is a novel pathogen first detected in respiratory tract samples in 2005. People of different ages can be infected by human bocavirus. Children are the susceptible population, especially the infants aged from 6-24 months old. The epidemic season varies in different regions due to the differences in climate and geographical location, and it mainly occurs in autumn and winter. It's demonstrated that human bocavirus-1 is closely related to respiratory system diseases and even causes life-threatening critical illness. Also, the severity of symptom is positively correlated with viral load. Co-infections between human bocavirus-1 and other viruses often present high frequency occurrence. Human bocavirus-1 interferes immune function of host by inhibiting interferon secrete pathway. Currently, it remains limited knowledge and understanding of the roles of human bocavirus 2-4 in diseases, but the gastrointestinal diseases should be paid more attention. Detection of human bocavirus DNA by traditional polymerase chain reaction (PCR) assay shouldn't be regarded as conclusive diagnostic basis. Instead, combined with mRNA and specific antigen detection, it is beneficial to improve the accuracy of diagnosis. Till now, the knowledge of human bocavirus remains poorly studied, which is deserved to further progress.
Infant ; Humans ; Child ; Child, Preschool ; Human bocavirus ; Climate ; Coinfection ; Epidemics ; Interferons

PURPOSE: Excluding RSV, the relationship between bronchiolitis caused by viruses and the development of wheezing and atopy in childhood has not been well studied. We studied this relationship in children who had bronchiolitis caused by human bocavirus before 2 years of age. METHODS: We retrospectively investigated 2,430 throat swab obstained between January 2005 and December 2007 from pediatric in-patients with acute respiratory tract disease at the Kwangju Christian Hospital. Human bocavirus was detected in 112 patients. A total of 61 patients less than 2 years of age were finally enrolled in this study. Patients were followed up between April and June of 2008. We measured the frequency of wheezing and atopic status using (allergy skin-prick tests, CAP tests and MAST tests). RESULTS: Of the 61 patients, 16 (26.2%) had recurrent wheezing. Of these 16 patients, 8 (13.1%) had Infrequent wheezing (1-2 wheezing episodes) and 8 (13.1%) had frequent wheezing (3 and over wheezing episodes). Of the total 61 patients, 18 (29.5%) completed allergy tests. Of the 18 patients, 10 (55.6%) were sensitized to at least 1 allergen. Recurrent wheezing was significantly associated with the severity of bronchiolitis (mild vs. moderate vs. severe; 9.1% vs. 22.2% vs. 66.7%). CONCLUSION: Human bocavirus-induced bronchiolitis in childhood are an independent risk factor for development of wheezing in childhood and may be associated with an increased risk of allergic sensitization. The most important risk factor for recurrent wheezing is the severity of lower respiratory tract illnesses.
Bronchiolitis ; Child ; Human bocavirus ; Humans ; Hypersensitivity ; Korea ; Pharynx ; Respiratory Sounds ; Respiratory System ; Respiratory Tract Diseases ; Retrospective Studies ; Risk Factors

PURPOSE: Human bocavirus (hBoV), a recently discovered virus, has been detected in children with respiratory tract infections worldwide. The aim of this study was to analyze the frequency and molecular phylogeny of hBoV in the respiratory samples of children with acute respiratory tract infections in 2010. METHODS: Nasopharyngeal samples were collected from 953 children with lower respiratory tract infections at Severance children's hospital in Korea from January 2010 to December 2010. We applied the multiplex PCR technique for the identification of 12 respiratory viruses from the samples. Among the total specimens, hBoV positive samples were subjected to phylogenetic analysis by sequencing a fragment of the VP1/VP2 gene junction. RESULTS: hBoV was detected in 141 (14.8%) among 953 patients. The 61.7% of hBoV-positive samples were found to co-exist with other respiratory viruses. The results of phylogenetic analysis showed that all 141 hBoV-positive isolates were identified as hBoV 1, revealing a high similarity among the isolates (>98%). CONCLUSION: hBoV 1 with minimal sequence variations circulated in children with acute respiratory infections during 2010. More research is needed to determine the clinical severity and outcomes of the minimal sequence variations.
Child ; Child, Hospitalized ; Human bocavirus ; Humans ; Korea ; Multiplex Polymerase Chain Reaction ; Phylogeny ; Respiratory System ; Respiratory Tract Infections ; Viruses

PURPOSE: It is well known that respiratory viral infection has epidemiological characteristics, including season. This study aimed to investigate the patterns of the prevalence of common respiratory viruses during a period of 10 years with regard to age, sex, and season in Korean children. METHODS: From June 2006 to November 2016, we obtained 11,798 specimens from patients aged less than 18 years who were admitted with lower respiratory infections. Ten respiratory viruses were detected using multiplex reverse transcription-polymerase chain reaction. RESULTS: Of 11,798 specimens, at least 1 virus was detected in 4,845 (41.1%). Respiratory syncytial virus (RSV, 18.9%) was the most common virus detected, followed by human rhinovirus (HRV, 14.8%), adenovirus (9.5%), and human bocavirus (HBoV, 7.4%). The detection rate of HRV was higher in male subjects (male 60.0% vs. female 40.0%, P=0.004), but the other viruses had no significant differences with regard to sex. The subjects who were positive for RSV test were youngest (median, 10.5 months; interquartile range, 3.0–25.0 months), followed by human coronavirus (median, 13.0 months), HRV (median, 14 months), and parainfluenza (median, 14 months). HBoV was most commonly detected in spring (29.3%), enterovirus in summer (25.8%), HRV in fall (22.6%), and RSV in October and winter (22.6%). CONCLUSION: We found that the prevalence of respiratory viruses in Korean children during a period of 10 years was associated with age, sex, and season when the infection occurred. Further nationwide data is warranted to infer clinical implication of our results.
Adenoviridae ; Child* ; Coronavirus ; Enterovirus ; Female ; Human bocavirus ; Humans ; Male ; Paramyxoviridae Infections ; Prevalence* ; Respiratory Syncytial Viruses ; Respiratory Tract Infections ; Rhinovirus ; Seasons*

OBJECTIVETo investigate the status of human bocavirus and to identify its epidemiological characteristics as well as genotype distribution in patients with infantile viral diarrhea in Suzhou, Jiangsu province.

METHODS832 fecal specimens from patients with infantile virus diarrhea cases were collected from Suzhou Children's Hospital in 2010-2011. Human bocavirus were detected by Real-Time RT-PCR, and genotype were determined by sequence analysis.

RESULTSAmong all the fecal specimens, 51 (6.1%) cases were positive for human bocavirus. The peak season of rotavirus infection was between July and September. Of all the episodes on rotavirus diarrhea, 96% occurred before 2 years of age, with peaks in children with 7-12 months of age. Data from Nucleotide Sequence analysis showed that among 28 samples that carrying HBoV-1, 5 strains belonged to HBoV-2, HBoV type 3 but type 4 were absent.

CONCLUSIONHuman bocavirus were detected from fecal specimens of infantile virus diarrhea in Suzhou, with genotype HBoV-1 as the major strain. HBoV-2 genotype was also found.

China ; epidemiology ; Diarrhea, Infantile ; epidemiology ; virology ; Female ; Genotype ; Human bocavirus ; genetics ; isolation & purification ; Humans ; Infant ; Male ; Phylogeny ; Sequence Analysis, DNA

OBJECTIVETo study the clinical and molecular epidemiology characteristics of human Bocavirus 1-3 (HBoV1-3) in children for acute respiratory infection in Lanzhou area.

METHODSNasopharyngeal aspiration samples and throat swabs were collected from 524 children with ARTI at the First Hospital of Lanzhou University, Gansu Province, China, between December 2009 and November 2010. Nested PCR was employed to screening HBoV1-3, which amplified a 518-bp fragment of the partial NS1 gene. Furthermore, a standard reverse transcription-PCR was used to screen for other common respiratory viruses.

RESULTSThe overall frequency of HBoV was 8.2% (43/524), lining up behind human rhinovirus, RSV, parainfluenza virus 3. Thirty of the HBoV-postive children(69.8%) were co-infected with other respiratory viruses. The prevalence of HBoV1 in ALRTI was obviously higher than that in AURI. The 2 HBoV2 NS1 sequences shared 99% and 100% nucleotide sequence identity with HBoV2 strain CU47TH respectively. Two cases of HBoV2 postive children appears gastrointestinal symptoms. The one HBoV3 NS1 sequences shared 99% nucleotide sequence identity with HBoV3 isolate 46-BJ07.

CONCLUSIONThe HBoV3 was detected at the first time in lanzhou area. HBoV1-3 infection exists in children with acute respiratory tract infections in Lanzhou region, HBoV1 were dominant. The mixed infection rate was higher.

Acute Disease ; China ; Female ; Human bocavirus ; classification ; genetics ; isolation & purification ; Humans ; Infant ; Male ; Phylogeny ; Respiratory Tract Infections ; virology