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1.
J Med Virol ; 96(1): e29429, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38258346

RESUMO

This study aimed to investigate the frequency and genotypic diversity of human bocavirus (HBoV) in historical fecal samples collected before 2005 in Brazil and understand its natural history in patients with diarrhea. Between 1998 and 2005, 3347 samples were tested for HBoV by RT-PCR, with a detection rate of 5.8% (195/3347). Coinfection with norovirus (NoV) and human adenovirus (HAdV) was found in 34.9% (68/195), indicating HBoV's potential role as a causative agent of diarrheal disease. The detection rate varied over the years (p < 0.05), suggesting natural oscillatory fluctuations. HBoV was more prevalent in fall and winter, with higher positivity in children ≤5 years (p < 0.05), reinforcing that HBoV is an important pathogen in childhood diarrhea. Genotyping (32.8%; 64/195) revealed the circulation of HBoV-1 (79.7%, 51/64), HBoV-3 (12.5%, 8/64), HBoV-2 (6.2%, 4/64), and the rare HBoV-4 (1.6%, 1/64). Difference in HBoV-1 and HBoV-2/-3 mono-infections prevalence (p < 0.05), suggests a potential role of HBoV-1 in the pathogenicity of diarrheal disease. The study highlights HBoV's lasting impact on viral gastroenteritis in Brazil and emphasizes its genotypic diversity. Recommending screening for HBoV in public health laboratories is crucial for understanding its role in gastrointestinal diseases. The data also contribute to understanding the molecular characterization of enteric viruses in historical fecal samples.


Assuntos
Adenovírus Humanos , Infecções por Enterovirus , Bocavirus Humano , Criança , Humanos , Brasil/epidemiologia , Bocavirus Humano/genética , Diarreia/epidemiologia , Genótipo
2.
Braz J Microbiol ; 55(1): 315-322, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38019412

RESUMO

Human bocaparvoviruses (HBoVs) belong to the Parvoviridae family, being currently classified into four species (HBoV1-4). These viruses have been found in association with respiratory and gastroenteric symptoms, as well as in asymptomatic individuals. This study aimed to investigate the occurrence of HBoVs in infants under 5 months old admitted to a Neonatal Intensive Care Unit (NICU) during the COVID-19 pandemic (between March 2021 and March 2022). Clinical samples (nasopharyngeal swab, serum, stool, and urine) were screened by qPCR TaqMan. The HBoV was detected in samples of 31.6% (12/38) of participants. The most frequent alteration among the HBoV-positive neonates was the chest X-ray with interstitial infiltrate, followed by tachycardia and vomiting. Viral DNA was detected in more than one type of clinical sample in three of the participants in association with respiratory symptoms. Two participants had positive stool samples with or without enteric symptoms. HBoV intermittent and continuous positivity patterns were observed. The present study stands out for the prospective evaluation of positivity for HBoV in different types of clinical samples from a population of hospitalized infants. Our data supports circulation of HBoV in nosocomial environment during the COVID-19 pandemic.


Assuntos
COVID-19 , Bocavirus Humano , Infecções por Parvoviridae , Infecções Respiratórias , Lactente , Recém-Nascido , Humanos , Unidades de Terapia Intensiva Neonatal , Brasil/epidemiologia , Pandemias , Bocavirus Humano/genética , COVID-19/epidemiologia
3.
Rev Med Virol ; 33(6): e2482, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37749807

RESUMO

Human bocaviruses were first described between 2005 and 2010, identified in respiratory and enteric tract samples of children. Screening studies have shown worldwide distribution. Based on phylogenetic analysis, they were classified into four genotypes (HBoV1-4). From a clinical perspective, human bocavirus 1 (HBoV1) is considered the most relevant, since it can cause upper and lower acute respiratory tract infection, mainly in infants, including common cold, bronchiolitis, and pneumonia, as well as wheezing in susceptible patients. However, the specific processes leading to structural, biochemical, and functional changes resulting in the different clinical presentations have not been elucidated yet. This review surveys the interactions between the virus and target cells that can potentially explain disease-causing mechanisms. It also summarises the clinical phenotype of cases, stressing the role of HBoV1 as an aetiological agent of lower acute respiratory infection in infants, together with laboratory tests for detection and diagnosis. By exploring the current knowledge on the epidemiology of HBoV1, insights into the complex scenario of paediatric respiratory infections are presented, as well as the potential effects that changes in the circulation can have on the dynamics of respiratory agents, spotlighting the benefits of comprehensively increase insights into incidence, interrelationships with co-circulating agents and potential control of HBoV1.


Assuntos
Bocavirus Humano , Infecções por Parvoviridae , Infecções Respiratórias , Lactente , Criança , Humanos , Bocavirus Humano/genética , Filogenia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Replicação Viral , Comunicação Celular , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/epidemiologia
4.
Viruses ; 15(4)2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37113004

RESUMO

Human bocavirus (HBoV) is an emerging virus detected around the world that may be associated with cases of acute gastroenteritis (AGE). However, its contribution to AGE has not been elucidated. This study aimed to describe the frequency, clinical features, and HBoV species circulation in children up to 5 years with or without AGE symptoms in Acre, Northern Brazil. A total of 480 stool samples were collected between January and December 2012. Fecal samples were used for extraction, nested PCR amplification, and sequencing for genotyping. Statistical analysis was applied to verify the association between epidemiological and clinical characteristics. Overall, HBoV-positivity was 10% (48/480), with HBoV-positive rates of 8.4% (19/226) and 11.4% (29/254) recorded in diarrheic and non-diarrheic children, respectively. The most affected children were in the age group ranging between 7 and 24 months (50%). HBoV infection was more frequent in children who live in urban areas (85.4%), use water from public networks (56.2%), and live with adequate sewage facilities (50%). Co-detection with other enteric viruses was 16.7% (8/48) and the most prevalent coinfection was RVA+ HBoV (50%, 4/8). HBoV-1 was the most frequent species detected in diarrheic and non-diarrheic children, responsible for 43.8% (21/48) of cases, followed by HBoV-3 (29.2%, 14/48) and HBoV-2 (25%, 12/48). In this study, HBoV infection was not always associated with AGE, as most HBoV cases belonged to the non-diarrheal group. Future studies are warranted in order to determine the role of HBoV in causing acute diarrhea disease.


Assuntos
Bocavirus , Gastroenterite , Bocavirus Humano , Infecções por Parvoviridae , Infecções Respiratórias , Humanos , Criança , Lactente , Pré-Escolar , Bocavirus Humano/genética , Brasil/epidemiologia , Infecções por Parvoviridae/epidemiologia , Gastroenterite/epidemiologia , Diarreia/epidemiologia , Fezes , Doença Aguda
5.
J Med Microbiol ; 71(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36301612

RESUMO

Introduction. Human bocavirus 1 (HBoV1) infection occurs with viral genome presence in respiratory secretions (RS) and serum, and therefore both samples can be used for diagnosis.Gap statement. The diagnostic sensitivity of HBoV1 DNA detection in serum and the duration of DNAaemia in severe clinical cases have not been elucidated.Aim. To determine HBoV1 DNA in serum and RS of paediatric patients hospitalized for lower acute respiratory infection (LARI) and to analyse the clinical-epidemiological features of positive cases.Methodology. This was a prospective, transverse study. Physicians selected the clinical situations and obtained paired clinical samples (RS and serum) that were tested by PCR/qPCR for HBoV1. Positive cases were analysed considering time of specimen collection, co-detection, clinical manifestations and viral load; statistical significant level was set at α=0.05.Results. HBoV1 was detected in 98 of 402 cases included (24 %); 18/98 (18 %) patients had the virus detectable in serum and 91/98 (93 %) in RS (P<0.001). Positivity rates were not significantly different in patients with RS and serum collected within or beyond 24 h of admission. Single HBoV1 infection was identified in 39/98 patients (40 %), three patients had HBoV1 in both clinical samples (3/39, 8 %) and 32 (32/39, 82 %) only in RS, 22 of them (69 %) with both clinical samples within 24 h of admission. Cough (P=0.001) and rhinitis (P=0.003) were significantly frequent among them and most patients were diagnosed with bronchiolitis (22/39, 56 %) and pneumonia (9/39, 23 %), which was more frequent compared to cases with co-infection (P=0.04). No significant differences were identified among patients with high, medium or low viral load of HBoV1 regarding rate of positivity in both clinical samples, the time of collection of RS and serum, co-detection, first episode of LARI, clinical manifestations, comorbidity or requirement for assisted ventilation. Intensive care unit (ICU) patients had a significantly higher frequency of detection (P<0.001) and co-detection (P=0.001) compared to patients on standard care.Conclusions. HBoV1 is prevalent among infant patients hospitalized for LARI and including it in the standard testing can add to the aetiological diagnosis in these cases, especially for patients admitted to the ICU. HBoV1 detection in serum did not contribute significantly to the diagnosis as compared to detection in respiratory secretions.


Assuntos
Bocavirus Humano , Infecções por Parvoviridae , Infecções Respiratórias , Lactente , Humanos , Criança , Bocavirus Humano/genética , Estudos Prospectivos , Infecções por Parvoviridae/diagnóstico , Infecções Respiratórias/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real
6.
Braz J Microbiol ; 53(4): 1915-1924, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35933553

RESUMO

The human bocavirus (HBoV) is an agent of upper and lower respiratory infections, affecting mainly children under 5 years of age. Community-acquired pneumonia (CAP) is an important public health problem in developing countries, representing one of the main causes of hospitalizations and deaths in children. The aim of this study was to describe the prevalence of HBoV and the clinical and epidemiological characteristics in children diagnosed with CAP. For this purpose, nasopharyngeal aspirates were collected from 545 children aged 0 to 60 months diagnosed with CAP between January 2013 and December 2014 in a reference pediatric hospital in Fortaleza, Ceará, Brazil. The samples were subjected to PCR for detection of HBoV and parainfluenza 4 (PIV4) and indirect immunofluorescence for detection of respiratory syncytial virus (RSV), adenovirus (AdV), influenza A and B (FLU A and FLU B), and parainfluenza 1, 2, and 3 (PIV1, PIV2, PIV3). Clinically, most CAP were non-complicated (487/545; 89.3%); however, 10.7% (58/545) of children were treated in the ICU/resuscitation sector. Among the total samples analyzed, 359 (65.8%) were positive for at least one virus surveyed and 105 (19.2%) samples had two or more viruses. HBoV was detected in 87 samples (15.9%), being the second most prevalent virus. RSV, AdV, FLU A, FLU B, and PIV 1-3 were detected in 150 (27.5%), 45 (8.2%), 30 (5.5%), 3 (0.5%), and 131 (24%) samples, respectively. The age average was 12.1 months in children infected with HBoV, and the most frequent symptoms were dyspnea and cough. In addition, 90.6% of HboV-positive children received antibiotics as empirical treatment. HBoV did not show any circulation pattern; however, it seemed to be more frequent in the first half of the year, totaling 68.9% of the cases. HBoV is a frequent agent of pneumonia in the child population studied.


Assuntos
Infecções Comunitárias Adquiridas , Bocavirus Humano , Infecções por Paramyxoviridae , Infecções por Parvoviridae , Pneumonia , Infecções Respiratórias , Criança , Humanos , Lactente , Pré-Escolar , Bocavirus Humano/genética , Brasil/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Vírus Sinciciais Respiratórios , Infecções por Parvoviridae/epidemiologia
7.
J Med Virol ; 94(2): 594-600, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-30982975

RESUMO

OBJECTIVES: The aim of this study was to evaluate the occurrence of human bocavirus (HBoV) and to determine viral loads in samples of patients admitted for allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Fecal and serum samples were collected from 19 patients, during a 24-month period. Samples were screened by quantitative polymerase chain reaction TaqMan assay, with specific probe and primers targeting the NP1 gene of all HBoVs genotypes (HBoV-1 to - 4), and viral loads were determined using serial dilutions of a recombinant plasmid. RESULTS: HBoV DNA was detected in 42.1% (8 of 19) of the patients in at least one type of sample (feces and/or serum) during the study period, with 75% (6 of 8) of the patients being positive in both types of sample. Viral shedding in feces had a median of 26 days (range, 5 to 121) and viremia was detected in 87.5% (7 of 8) of the patients. The HBoV loads in fecal samples were higher than in sera and, in most cases, HBoV was detected earlier in fecal than in sera samples. In six HBoV-positive patients (6 of 8) diarrhea was observed concomitantly to viral detection in fecal samples. CONCLUSIONS: A high frequency and loads of HBoV in allo-HSCT recipients was observed, especially in fecal samples. Positivity in fecal samples was an early predictor of HBoV presence.


Assuntos
Fezes/virologia , Transplante de Células-Tronco Hematopoéticas , Bocavirus Humano/genética , Infecções por Parvoviridae/virologia , Viremia/sangue , Adolescente , Adulto , Brasil , Feminino , Genótipo , Hospitalização , Bocavirus Humano/isolamento & purificação , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Carga Viral , Eliminação de Partículas Virais , Adulto Jovem
8.
J Med Virol ; 93(11): 6132-6139, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34050944

RESUMO

Cholesteatomas are frequent middle ear benign tumors of unknown etiology. Infectious agents have been considered as possible contributing factors in the pathogenesis of cholesteatomas. Aiming to investigate the presence of respiratory viruses in primary cholesteatoma tissues, 26 formalin-fixed paraffin-embedded primary cholesteatoma tissues obtained from patients seen at the of the Clinical Hospital of the University of São Paulo School of Medicine, in Ribeirão Preto, Brazil were tested by real-time polymerase chain reaction (PCR). Considering the PCR results, 35% of the tissues were positive for human rhinovirus (HRV), 15.3% for human enterovirus (EV), 3.8% for human metapneumovirus (HMPV), and 3.8% for human bocavirus (HBoV). Serial immunohistochemistry for virus antigens and cell surface markers evidenced that the viruses were associated with fibroblasts, dendritic cells, macrophages, B lymphocytes, CD4+ , and CD8+ T lymphocytes. These findings indicate for the first time the presence of active respiratory virus infection in primary cholesteatoma tissues, suggesting that persisting virus infection in the middle could play a role in the pathogenesis and evolution of cholesteatomas.


Assuntos
Colesteatoma/virologia , Enterovirus/isolamento & purificação , Bocavirus Humano/isolamento & purificação , Metapneumovirus/isolamento & purificação , Rhinovirus/isolamento & purificação , Adolescente , Adulto , Idoso , Brasil , Colesteatoma/patologia , Estudos Transversais , Enterovirus/genética , Feminino , Bocavirus Humano/genética , Humanos , Masculino , Metapneumovirus/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Rhinovirus/genética , Adulto Jovem
9.
Int J Infect Dis ; 95: 32-37, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32251804

RESUMO

OBJECTIVES: This study aimed to verify the frequency, genotypes, and etiological role of Human Bocavirus (HBoV) in younger Amazonian children with either acute gastroenteritis (AGE) or respiratory infections (ARI). The influence of Rotarix™ vaccination and co-infection status was also investigated. DESIGN: HBoV quantitative polymerase chain reaction (qPCR) testing was done on both fecal and saliva (1468 samples) from 734 children < 5 months old living in the Amazon (Brazil, Guyana, and Venezuela). High and median HBoV viral load samples were used for extraction, nested PCR amplification, and sequencing for genotyping. HBoV mRNA detection was done by reverse transcription following DNA amplification. RESULTS: The overall HBoV frequencies were 14.2% (69/485; AGE) and 14.1% (35/249; ARI) (p = 0.83). HBoV exclusively infected 4.5% (22/485; AGE) and 4% (10/249) of the Amazonian children (Odds ratios 1.13, 95% confidence interval= 2.42-0.52). HBoV 1 was mainly detected in feces and saliva from AGE children; and HBoV2, from ARI children. HBoV mRNA was detected only in feces. The Rotarix™ vaccination status did not affect the HBoV frequencies. CONCLUSIONS: We suggest that, after entry into the air/oral pathways, HBoV1 continues infecting toward the intestinal tract causing AGE. HBoV2 can be a causative agent of AGE and ARI in younger Amazonian children.


Assuntos
Gastroenterite/virologia , Bocavirus Humano/genética , Infecções por Parvoviridae/virologia , Infecções Respiratórias/virologia , Doença Aguda , Brasil , Coinfecção/virologia , Fezes/virologia , Feminino , Genótipo , Guiana , Bocavirus Humano/isolamento & purificação , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Saliva/virologia , Venezuela , Carga Viral
10.
Braz J Microbiol ; 51(1): 45-51, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31522356

RESUMO

The objective of this study was to determine the frequency and seasonal distributions of HBoV detections among Iranian children presenting with acute respiratory or gastrointestinal symptoms and to compare infections among children with concomitant respiratory syncytial virus (RSV) and rotavirus (RV) infections. A cross-sectional study at Mofid Children's Hospital in Tehran, Iran, enrolled children < 3 years old presenting with either acute respiratory or gastrointestinal symptoms during the period of 2017-2018. Respiratory or stool specimens collected from each group were initially tested by RT-PCR assays for RSV and RV, respectively, and all specimens were tested for HBoV by PCR assay. Clinical and demographic data were collected and statistically compared. Five hundred respiratory and stool specimens each were tested and 67 (13.4%) and 72 (14.4%) were PCR positive for HBoV, respectively. Of 128 (25.6%) respiratory specimens positive for RSV, 65% were also positive for HBoV (p = 0.019); of 169 (33.8%) stool specimens positive for RV, 62.5% were also positive for HBoV (p = 0.023). Peak circulation of all viruses was during late winter and early spring months (Jan-Mar) in gastrointestinal infections and during winter (Feb-Jan) in respiratory infections. HBoV is commonly detected among Iranian children presenting with acute respiratory or gastrointestinal symptoms and is often present as co-infections with RSV and RV, respectively.


Assuntos
Coinfecção/epidemiologia , Gastroenteropatias/virologia , Infecções por Parvoviridae/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções Respiratórias/virologia , Estações do Ano , Doença Aguda/epidemiologia , Pré-Escolar , Coinfecção/virologia , Estudos Transversais , Fezes/virologia , Feminino , Gastroenteropatias/epidemiologia , Bocavirus Humano/genética , Bocavirus Humano/patogenicidade , Humanos , Lactente , Irã (Geográfico)/epidemiologia , Masculino , Nasofaringe/virologia , Vírus Sinciciais Respiratórios/genética , Vírus Sinciciais Respiratórios/patogenicidade , Infecções Respiratórias/epidemiologia , Rotavirus/genética , Rotavirus/patogenicidade
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