Clinical characterization of human bocavirus 1 infection in infants hospitalized in an intensive care unit for severe acute respiratory tract disease

Acute respiratory infections represent the leading cause of morbimortality in children and viruses are the main etiological agents. Here we describe the clinical characteristics and evolution of infants admitted to intensive care unit with severe acute respiratory infection (SARI) due to Human Bocavirus 1 mono-infection in patients without previous comorbidity. We also compared them with respiratory syncytial virus (RSV) cases. Of 141 cases included (age 5.43 ± 4.54 months, 52% male), 80% had at least 1 virus detected. RSV was the most frequent in the series (71.6%) followed by HBoV1 (28%). Five cases of HBoV1 mono-detection were identified. Pediatric acute respiratory distress syndrome was present in both groups, HBoV1 and RSV. The clinical presentation and evolution of HBoV1 single infection was similar to RSV. HBoV1 should be included among the agents investigated in cases of SARI in infants.

Plastic bronchitis secondary to bocavirus in a previously healthy 4-year-old with negative lymphatic evaluation

This case of a child presenting with severe acute respiratory failure requiring extracorporeal membrane oxygenation due to plastic bronchitis demonstrates the possibility of developing this rare condition despite having no known underlying inflammatory or lymphatic issues. The normal lymphatic anatomy and flow in our patient several weeks after the acute illness suggests a transient lymphatic flow abnormality possibly driven by the acute lower respiratory tract infection with human bocavirus-1 (HBoV1). As there are now four patients in the literature identified with Plastic bronchitis (PB) in the setting of HBoV1, it may be beneficial to include HBoV1 in the initial workup of patients with unknown etiology of PB. While routine use of MR lymphangiography is not warranted, we wonder if the procedure might help realize lymphatic flow abnormalities crucial to the pathophysiology if it can be performed safely in the acute setting. The heterogeneous population presents a challenge when studying PB, thus future studies are needed to elucidate the complex pathophysiology, guide management, and better understand prognosis.

Acute encephalopathy with biphasic seizures and late restricted diffusion temporally associated with human bocavirus infection

Acute encephalitis is a syndromic diagnosis. In the last two decades, a unique clinico-radiological entity, named acute encephalopathy with biphasic seizures and late restricted diffusion (AESD), has been reported in children from Asia. It is characterised by an acute febrile illness with seizures and encephalopathy, with some initial improvement followed by a second flurry of seizures and deep encephalopathy, 3-4 days later. MRI may show a pattern of 'bright tree appearance'. An aetiological agent may not always be identified but an infectious trigger is proposed. Immunomodulatory therapy has been tried with variable results. The prognosis is variable, and children are usually left with neurological sequelae including epilepsy and cognitive impairment. We describe a female infant who presented with the typical clinico-radiological syndrome of AESD and human bocavirus was identified in the stool. She received steroids and antiepileptic drugs. She has persistent cognitive impairment at follow-up but remained seizure free.

Case Report: Bocavirus Infection Radiologically Resembling a Congestive Heart Failure in a Patient with Metastatic Castration-Resistant Prostate Cancer

Background: Human bocavirus (HBoV) is a viral pathogen from the genus Bocaparvovirus (family Parvoviridae, subfamily Parvovirinae) discovered in 2005. Most of available literature is about HBoV in children and adults with hematological malignancies and in otherwise healthy children with respiratory infections. Information regarding infection in the adult population with solid tumors is scarce. Case Report: We report the case of a 51-year-old male with metastatic castration resistant prostate cancer undergoing chemotherapy treatment who presented with fever, dyspnea, dry cough, and pleuritic pain. Imaging techniques showed signs of congestive heart failure. Symptoms, laboratory tests and echocardiography revealed a more probable infectious etiology. Antibiotic therapy was started. A polymerase chain reaction (PCR) test of nasopharyngeal exudate for respiratory viruses was positive for HBoV. The rest of the microbiological tests were negative. Bronchoalveolar lavage (BAL) was performed. Bacterial culture of BAL was negative while respiratory virus PCR confirmed positivity for HBoV. Antibiotic therapy was discontinued. The patient gradually recovered. Conclusions: Emerging infectious diseases are a notorious threat for immunocompromised populations such as solid tumor patients. This case is unique because to our knowledge this is the first case report article of HBoV in a solid tumor patient and because imaging techniques exhibited signs of congestive heart failure that did not correlate with the rest of the tests. It shows that unusual pathogens should be considered when managing serious clinical complications with uncommon presentations in cancer patients. Notable diagnostic efforts should be made to reach a diagnosis in these cases.

EPIDEMIOLOGY OF RESPIRATORY PATHOGENS IN CHILDREN WITH ACUTE RESPIRATORY TRACT INFECTION IN UKRAINE DURING 2018-2020 YEARS

OBJECTIVE

The aim: Is to provide data on the presence of potential pathogens of ARTIs in children in Ukraine.

PATIENTS AND METHODS

Materials and methods: The etiology of ARTIs was investigated in 487 children in MC 'Eurolab', Kyiv, Ukraine during 2018-2020 years. Seven respiratory viruses - Respiratory Syncytial virus (RSV), Parainfluenza virus (PIV), Adenovirus (AdV), human Metapneumovirus (MPV), Rhinovirus (RV), human Bocavirus (BoV), Coronavirus (CoV), were identified by PCR. Qualitative detection of Influenza type A, type B, Group A Streptococcal was performed by chromatographic immunoassay. Pathogens profiles, clinical characteristics and seasonality were analyzed.

RESULTS

Results: 487 nasal and throat swabs from children with ARVI were collected. 400 (82,1%) samples were found to be positive: 319 swabs were positive at least for one respiratory virus, 43 children had positive rapid influenza test, 38 - positive strep test. A total of 403 viruses were identified. RV (27,1%), ADV (13,4%), RSV (13,2 %), IVA (10,7 %) were the most commonly identified viruses.

CONCLUSION

Conclusions: Detection of viral seasonality in Ukraine and estimating of clinical features in case of infection allows predicting probable clinical course of disease, to provide, optimize the therapy and to develop preventive measures, vaccination, in particular.

Environmental monitoring of Aichi virus and human bocavirus in samples from wastewater treatment plant, drain, and River Nile in Egypt

Wastewater plays a major role in water pollution causing transmission of several viral pathogens, including Aichi virus (AiV) and human bocavirus (HBoV), associated with gastrointestinal illness in humans. In this study, we investigated the presence of AiV and HBoV in aquatic, sludge, sediment matrices collected from Abu-Rawash wastewater treatment plant (WWTP), El-Rahawy drain, Rosetta branch of the River Nile in Egypt by conventional polymerase chain reaction (PCR). AiV RNA was detected in 16.6% (2/12), 8.3% (1/12), 8.3% (1/12), 22% (16/72), 12.5% (3/24), 4% (1/24), and 0/24 (0%) of untreated raw sewage, treated sewage, sewage sludge, drainage water, drain sediment, river water, and river sediment, respectively. On the other hand, HBoV DNA was detected in 41.6% (5/12), 25% (3/12), 16.6% (2/12), 48.6% (35/72), 29% (7/24), 3/24 (12.5%), 4% (1/24) of untreated raw sewage, treated raw sewage, sewage sludge, drainage water, drain sediment, river water, and river sediment, respectively. This study provides data on the presence of these viruses in various types of water samples that are valuable to environmental risk assessment. In addition, the current study demonstrates the importance of environmental monitoring as an additional tool to investigate the epidemiology of AiV and HBoV circulating in a given community.

Human Bocavirus as a Possible Contributor to Respiratory Disease in the Georgian Military Population

The coronavirus disease 2019 (COVID-19) pandemic has demonstrated that new and devastating respiratory pathogens can emerge without warning. It is therefore imperative that Special Operations medical personnel be aware of the presence of emerging pathogens within their area of operation. Human bocavirus (HBoV) is a newly described member of a family of viruses known as the Parvovirinae that are often associated with acute respiratory illness. The presence of HBoV in the country of Georgia has not been previously reported. Nasal and throat swabs were collected from 95 symptomatic members of the Georgian military. HBoV was detected in 11 of them (12%). To our knowledge, this is the first report of HBoV infection in the country of Georgia. This finding may have a significant impact on members of the Special Operations community who train in Georgia as more data concerning the transmission, pathogenesis, and treatment of HBoV are accumulated and the role of HBoV in human disease is more clearly defined.

iTRAQ-based high-throughput proteomics analysis reveals alterations of plasma proteins in patients infected with human bocavirus

Human bocavirus (HBoV) is a member of the genus Bocavirus, family Parvoviridae, and subfamily Parvovirus and was first identified in nasopharyngeal aspirates of Swedish children with acute respiratory tract infection (ARTI) in 2005. It is the causative agent of nasopharyngeal aspirate disease and death in children. The HboV genomic structure is a linear single-stranded DNA (ssDNA). Its clinical pathogenic characteristics have been extensively studied, however, at present the molecular mechanism underlying the pathogenesis of HBoV infection is not completely clear. In this study, a total of 293 differentially expressed proteins (DEPs) between ARTI cases and healthy plasma samples were characterized using isobaric tags for relative and absolute quantitation (iTRAQ)-coupled bioinformatics analysis, among which 148 were up-regulated and 135 were down-regulated. Gene Ontology (GO) and Cluster of Orthologous Groups of proteins (COG) annotated an enrichment of DEPs in complement activation and biological processes like immunity, inflammation, signal transduction, substance synthesis, and metabolism. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis enriched DEPs mainly in the Wnt signaling pathway (ko04310), PPAR signaling pathway (ko03320), intestinal immune network for IgA production (ko04672), complement and coagulation cascades (ko04610), Toll-like receptor signaling pathway (ko04620) and B cell receptor signaling pathway (ko04662). Further, expression levels of three candidate proteins (upregulated PPP2R1A and CUL1, and downregulated CETP) were validated using western blotting. Our investigation is the first analysis of the proteomic profile of HBoV-infected ARTI cases using the iTRAQ approach, providing a foundation for a better molecular understanding of the pathogenesis of ARTI in children.

[Human Bocavirus 1: role in the acute respiratory infection and epidemiology in Cordoba, Argentina]

Human bocavirus 1 (HBoV1) is an agent of acute respiratory infection frequent in children. It can cause pneumonia in infants, in the absence of epidemiological risk factors and comorbidities. Well-controlled studies of clinical cases and case series are still useful for the characterization of the clinicoepideiological features of the infection, while research dives on the molecular biology of the virus and the virus-cell relationship allowing to unveil tha natural history of the infection. This article reviews the state of the art and future perspectives on this new human parvovirus and its etiological role in the respiratory pathology.

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.

Case Report: Human Bocavirus Associated Pneumonia as Cause of Acute Injury, Cologne, Germany

Although the human bocavirus (HBoV) is known since a decade, limited information about its pathogenesis is available due to the lack of an animal model. Thus, clinical cases and studies are the major source of novel information about the course of infection and the related pathophysiology.In this context, a clinical case of an adult patient suffering from severe HBoV-pneumonia is described that was associated with loss of consciousness followed by acute rib fracture and subsequent neurological disorder.Following initial global respiratory dysfunction the clinical respiratory symptoms recovered but the neurological symptoms maintained after weaning and intensive care in the stroke unit. During the initial phase, an acute active HBoV infection was confirmed by positive polymerase chain reactions from bronchoalveolar lavage fluid and serum.The case further demonstrates that HBoV can cause severe pneumonia, induce secondary disease also in adults, and may be associated with neurological symptoms as previously assumed.

Emerging respiratory viruses other than influenza

Non-influenza respiratory virus infections are common worldwide and contribute to morbidity and mortality in all age groups. The recently identified Middle East respiratory syndrome coronavirus has been associated with rapidly progressive pneumonia and high mortality rate. Adenovirus 14 has been increasingly recognized in severe acute respiratory illness in both military and civilian individuals. Rhinovirus C and human bocavirus type 1 have been commonly detected in infants and young children with respiratory tract infection and studies have shown a positive correlation between respiratory illness and high viral loads, mono-infection, viremia, and/or serologically-confirmed primary infection.

Human bocavirus VP2 upregulates IFN-β pathway by inhibiting ring finger protein 125-mediated ubiquitination of retinoic acid-inducible gene-I

Precise regulation of innate immunity is crucial for maintaining optimal immune responses against infections. Whereas positive regulation of IFN signaling elicits rapid type I IFNs, negative regulation is equally important in preventing the production of superfluous IFNs that can be hazardous to the host. The positive regulators of IFN pathway are known to be the main targets of viruses to antagonize the innate immune system. Whether viruses target the negative regulators of IFN pathway remains to be fully investigated. In this study, we report that the structural protein VP2 of human Bocavirus modulates IFN pathway by targeting the ring finger protein 125 (RNF125), a negative regulator of type I IFN signaling, which conjugates Lys(48)-linked ubiquitination to retinoic acid-inducible gene-I (RIG-I) and subsequently leads to the proteasome-dependent degradation of RIG-I. VP2 not only upregulated Sendai virus (SeV)-induced IFNB promoter activity, but also enhanced SeV-induced IFN-β production at both mRNA and protein levels. In agreement, the level of Ser(396)-phosphorylated IFN regulatory factor 3 stimulated by SeV was enhanced in the presence of VP2. Furthermore, VP2 was demonstrated to physically interact with RNF125, resulting in the reduction of RNF125-mediated ubiquitination and proteasome-dependent degradation of RIG-I. Additional study indicated that endogenous RIG-I degradation was decreased in VP2-expressing cells. Our study delineates a unique phenomenon for aberrant activation of IFN regulatory factor 3 pathway and may represent a new mechanism underlying viral manipulation of the host immune system.

Incidence of recurrent wheezing in under 5-year-old human bocavirus infection during one year follow-up

BACKGROUND

Human bocavirus (HBoV) is a newly identified virus that can cause acute wheezing in young children. The present study aimed to evaluate the incidence and factors associated with recurrent wheezing during 1 year after HBoV lower respiratory tract infection (LRI).

MATERIAL AND METHOD

Children younger than 5 years old who were admitted to King Chulalongkorn Memorial Hospital between February 1, 2006 and September 30, 2008 due to LRI were recruited. Their nasopharyngeal aspirates were evaluated for respiratory virus by polymerase chain reaction (PCR) assays. Those who had positive PCR for HBoV and had no underlying diseases were studied. Their clinical presentations were evaluated and their clinical data about recurrent wheezing as well as pulmonary function tests were followed-up for 1 year.

RESULTS

Fifteen patients with HBoV-LRI were regularly followed-up. Seven patients (47%) had co-infection with other respiratory viruses. Generalized wheezing was the most common lung sign detected in 73% of cases (11 cases) and 36% (4 cases) of them responded well to bronchodilators. During one year follow-up, serial pulmonary function tests were normal in all cases and most patients were doing well. However 27% of HBoV infected patients (4 cases) developed recurrent wheezing associated with respiratory tract infections. Two of them had to be re-hospitalized. Compared to patients without recurrent wheezing, eosinophil count tended to be higher in those with recurrent wheezing and isolated HBoV infected patients tended to develop recurrent wheezing more than those with co-infection.

CONCLUSION

Acute wheezing is a common presenting lung sign in HBo V-LRI. Although the pulmonary function tests of all patients were normal, more than a quarter of patients suffered from recurrent wheezing during one-year follow-up.

Human bocavirus types 1, 2 and 3 in acute gastroenteritis of childhood

Aim:  Recently identified human bocavirus (HBoV) types 2 and 3 have been associated with acute gastroenteritis in children. We studied 878 stool specimens from children with acute gastroenteritis and 112 controls (43 children with unspecified fever, 33 with respiratory tract infection and 36 healthy children) for known HBoVs. The same specimens were previously studied for rotaviruses, noroviruses, sapoviruses, adenoviruses, coronaviruses and aichivirus.

Methods:  HBoVs were detected by PCR and positive amplicons were sequenced to identify HBoV1, HBoV2, HBoV3 and HBoV4.

Results:  HBoV of any type was found in 85 (9.7%) cases of acute gastroenteritis and in 6 (5.4%) controls. HBoV1 was detected in 49 (5.6%) cases and 2 (1.8%) controls, HBoV2 in 29 (3.3%) cases and 2 (1.8%) controls and HBoV3 in 8 (0.9%) cases and 2 (1.8%) controls. No HBoV4 was found. HBoV as a single infection was found in 16 (1.8%) cases and in 6 (5.4%) controls; in the remaining cases, a known gastroenteritis virus was also found. Among the single HBoV infections, HBoV2 was the most common type with 8 (50%) cases.

Conclusion:  HBoVs are rarely found alone in children with acute gastroenteritis. Further studies are warranted to confirm a possible specific association of HBoV2 with gastroenteritis.

[Clinical characteristics of human bocavirus infection in 90 children]

OBJECTIVE

To study the clinical characteristics of human bocavirus (HBoV) infection in children.

METHODS

Nasal and throat swab samples were collected in 843 children with lower respiratory tract infection. The multiple RT-PCR method was used to detect HBoV and six other common respiratory tract viruses. The clinical characteristics of HboV positive cases were investigated.

RESULTS

Among 843 cases, 90 were HboV positive (10.7%), 131 were respiratory syncytial virus (RSV) positive (15.5%), 117 were influenza virus positive (13.9%), 84 were parainfluenza virus positive (10.0%), 55 were rhinovirus positive (6.5%), 48 were coronavirus positive (5.7%), and 33 were human metapneumovirus positive (3.7%). Of the 90 HBoV infected patients, 45 (50%) showed a co-infection with other respiratory tract viruses. Among them, 33 were infected with one other type of virus (37%), 11 (12%) were infected with two other types of virus, and 1 case (1%) was infected with other three viruses. The HBoV positive rate in children with wheezing was significantly higher than those without wheezing (17.0% vs 9.2%; P<0.01). The common clinical manifestations of HBoV-infected patients included frequent coughing, wheezing and fever. There were no significant differences in the frequency of wheezing between HBoV and RSV infected patients.

CONCLUSIONS

HBoV positive rate detected from children with wheezing is higher than from children without wheezing, suggesting that apart from RSV, HBoV is another virus causing wheezing in children with respiratory tract infection. Co-infections of HBoV with other respiratory track viruses can be present in some patients.

[Characteristics and the prevalence of respiratory viruses and the correlation with climatic factors of hospitalized children in Suzhou children's hospital]

OBJECTIVE

To study the epidemiological characteristics of respiratory virus infection and its relations to climatic factors in Suzhou.

METHODS

From 2006 to 2009, viral etiology surveillance was conducted among 6655 children hospitalized with acute respiratory tract infections (ARIs). Direct immunofluorescence method was used to test respiratory secretion samples for respiratory syncytial virus (RSV), influenza viruses A and B (Inf-A, Inf-B), parainfluenza virus types I, II, and III (Pinf-I, Pinf-II, Pinf-III) and adenovirus. Samples were tested for human metapneumovirus (hMPV) with reverse transcription polymerase chain reaction (RT-PCR). Samples from Jan 2006 to Dec 2009 were also tested for human bocavirus (HBoV). Climatic factors, including mean temperature, relative humidity, rainfall amount, sum of sunshine and mean wind velocity were collected monthly. The relationship between activity of each virus and climatic factors were analyzed by linear regression and stepwise regression analysis.

RESULTS

From 2006 to 2009, in the total virus detection rate was 32.2% (2142/6655) in Suzhou. RSV was the most common virus and the average detection rate was 15.7% (1048/6655), followed by hMPV 8.9% (596/6655), HBoV 7.8% (148/1883), Pinf-III 2.7% (183/6655), Inf-A 2.4% (161/6655), ADV 1.3% (89/6655), Pinf-I 0.4% (29/6655), Inf-B 0.37% (25/6655) and Pinf-II 0.16% (11/6655). The positive rates of RSV, hMPV and ADV were significantly different in four years (χ(2) = 17.71, 33.23, 8.42, all P values < 0.05). Different virus has different epidemiological characteristics and distinct seasonality. The detection rate of RSV, hMPV, Inf-A were higher in Winter as 37.2%, 13.2%, 4.4%, respectively. ADV and Pinf-III were higher in summer as 2.3% and 4.6% respectively. The peak of HBoV existed in Autumn as 3.3%. The total virus detection rate showed significant inverse correlation with month average temperature (r = -0.732, P < 0.001) and a weak inverse correlation with average wind velocity was also found (r = -0.36, 0.01 < P < 0.05). The highest month total virus detection rate was from 47.6% to 84.4% when average temperature was from 3.2°C to 9.4°C and mean wind velocity was from 1.2 - 1.9 m/s. The associations of average temperature, sum of sunshine and wind velocity with RSV activity were statistical significant (r = -0.88, P < 0.001; r = -0.43, P < 0.01; r = -0.47, P < 0.01). The highest rate was from 24.3% to 58.2%, when mean temperature was from 5.3°C to 19.9°C, mean wind velocity was from 1.3 - 2.4 m/s and sum of sunshine was 61.0 to 153.4 hours. hMPV detection rate was inversely correlated with mean temperature and rain account (r = -0.43, P < 0.01; r = -0.29, P < 0.05). The rate was highest from 11.7% to 31.6% when mean temperature was from 5.3°C to 21.9°C and rain account was from 27.5 millimeter to 150.9 millimeter. Only mean temperature was positively correlated with Pinf-III (r = 0.53, P < 0.001). The rate was from 2.8% to 7.2% when mean temperature was between 11.9°C and 30.4°C. ADV detection rate was positively correlated with mean temperature and sum of sunshine, but negatively correlated with wind velocity (r = 0.35, P < 0.05; r = 0.30, P < 0.05; r = -0.32, P < 0.05). The rate was from 2.2% to 6.6% when mean temperature was between 15.9°C and 30.4°C, and sum of sunshine between 93 hours to 240.7 hours and mean wind velocity was from 1.1 - 2.8 m/s. Average temperature and relative humidity showed interactions on the detection rate of ADV (r = 0.36, P = 0.0093; r = -0.34, P = 0.016), but temperature showed higher effect on ADV detection rate. ADV detection rate was high at higher temperature (15.9 - 30.4°C) and low humidity (56% - 71%).

CONCLUSION

RSV was one of the most common viruses among hospitalized children in Suzhou, and hMPV and HBoV also played an important role in respiratory tract infection of children. Different virus has different cycle and seasonality. Climatic factors, especially mean temperature, was the main factor affecting the virus prevalence.