Severe Human Bocavirus-Associated Pneumonia in Adults at a Referral Hospital, Seoul, South Korea

Clinical and molecular characterization of children and adults with respiratory bocavirus infection in Mexico: a cross-sectional nested study within the ILI002 prospective observational study

Background

Human Bocaviruses (HBoV) can cause acute respiratory tract infections. High coinfection rates cloud its pathogenicity. This study sought to describe the clinical features of HBoV1 disease in children and adults with Influenza-like illness (ILI), exploring associations between viral load, clinical features, and seasonality.

Methods

Patients who tested positive for HBoV1 by polymerase chain reaction, enrolled from April 2010 to March 2014 in the ILI002 prospective observational cohort study were included in this cross-sectional nested study. Participants were included in ILI002 if they presented with signs and/or symptoms suggestive of influenza-like illness. Samples were tested for viral load, and NP1 and VP1/VP2 phylogenetic analyses, except for the samples lacking suitable and viable clinical material for genotyping.

Findings

We identified HBoV1 in 157 (2.8%) of participants. Prevalence was 4.5% in children and 1.8% in adults. Single HBoV1 detection occurred in 41.1% and 46.3% of children and adults, respectively. Children commonly experienced fever (83.3%), cough with sputum (74.4%), and shortness of breath (72.2%). In the multivariate analysis of children, significant positive associations were detected between viral loads and age (0.20 [95% CI: 0.07, 0.33]), and the presence of fever (2.64 [95% CI: 1.35, 3.94]), nasal congestion (1.03 [95% CI: 0.07, 1.99]), dry cough (1.32 [95% CI: 0.42, 2.22]), chest congestion (1.57 [95% CI: 0.33, 2.80]), red eyes (1.25 [95% CI: 0.35, 2.14]), cough with sputum (1.79 [95% CI: 0.80, 2.78]), and other signs and symptoms such as chills, dizziness, and diaphoresis (1.73 [95% CI: 0.19, 3.27]). In contrast, significant negative associations were found between viral loads and percent neutrophils on the blood count (-0.04 [95% CI: -0.06, -0.02]), fatigue (-1.60 [95% CI: -2.46, -0.74]) and the presence of other symptoms or signs, including adenopathy and rash (-1.26 [95% CI: -2.31, -0.21]). Adults commonly experienced sore throat (73.1%), fatigue (77.4%), and headache (73.1%). In the multivariate analysis of adults, significant positive associations were detected between viral load and body mass index (0.13 [95% CI: 0.04, 0.21]), and the presence of confusion (1.54 [95% CI: 0.55, 2.53]), and sore throat (1.03 [95% CI: 0.20, 1.85]), and significant negative associations were detected between viral load and chest congestion (-1.16 [95% CI: -2.07, -0.24]). HBoV1 was detected throughout the year irrespective of season, temperature, and humidity.

Interpretation

This study demonstrated the importance of detecting HBoV1 in patients with influenza-like illness either as single infection or co-infection, in both adults and children, and improves the characterization of HBoV1 seasonality, clinical features, and viral load. Phylogenetic analyses show a high conservation.

Funding

The Mexican Emerging Infectious Diseases Clinical Research Network (LaRed), CONACYT (Fondo Sectorial SSA/IMSS/ISSSTE, Projects No. 71260 and No. 127088), Fondos federales no. HIM/2015/006, NIAID, NIH through a contract with Westat, Inc. (HHSN2722009000031, HHSN27200002), NCI, NIH (75N91019D00024, 75N91019F00130). Additional information at the end of the manuscript.

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

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.

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 Human Bocavirus in the Middle East and North Africa: Systematic Review

The emergence of the COVID-19 pandemic highlighted the importance of studying newly emerging viruses that cause respiratory illnesses. Human bocavirus (HBoV) is one of the relatively newly discovered viruses that has been detected worldwide and causes respiratory and gastrointestinal infections, mainly in pediatric patients. However, little is known about the pathogenicity and evolution of HBoV. This systematic review was initiated to clarify the prevalence and circulating genotypes of HBoV in both respiratory and stool samples from patients of all age groups in the Middle East and North Africa (MENA) from 2005 to February 2021. We performed an electronic search through Science Direct, Scopus, PubMed, Mendeley and Cochrane Library databases. We included all studies reporting the detection rate of HBoV in the MENA region. Data were extracted, and the quality of the included articles was assessed. We included articles containing data on HBoV only or with other respiratory or gastrointestinal viral infections. Review articles, case studies, and animal and environmental studies were excluded. The final number of articles included in this study was 65 articles. The results showed that the HBoV prevalence in children was the lowest in Iran (0%) and the highest in Egypt (56.8%). In adults, the lowest and the highest prevalence were reported in Iran, with values of 0% and 6.6%, respectively. Regarding the respiratory cases, our findings revealed no significant difference between HBoV prevalence among the tested categories (p-value = 0.998). The present study has shown that HBoV is common in children and adults in the MENA region. This systematic review highlights the need for more data on the role of coinfection of HBoV and other viruses, for instance, SARS-CoV-2 in children with acute bronchiolitis.

Seasonal Coronaviruses and Other Neglected Respiratory Viruses: A Global Perspective and a Local Snapshot

Respiratory viral infections are the leading cause of morbidity and mortality in the world; however, there are several groups of viruses that are insufficiently routinely sought for, and can thus be considered neglected from a diagnostic and clinical standpoint. Timely detection of seasonality of certain respiratory viruses (e.g., enveloped viruses such as seasonal coronaviruses) in the local context can aid substantially in targeted and cost-effective utilization of viral diagnostic approaches. For the other, non-enveloped and year-round viruses (i.e., rhinovirus, adenovirus, and bocavirus), a continuous virological diagnosis needs to be implemented in clinical laboratories to more effectively address the aetiology of respiratory infections, and assess the overall impact of these viruses on disease burden. While the coronavirus disease 2019 (COVID-19) pandemic is still actively unfolding, we aimed to emphasize the persistent role of seasonal coronaviruses, rhinoviruses, adenoviruses and bocaviruses in the aetiology of respiratory infections. Consequently, this paper concentrates on the burden and epidemiological trends of aforementioned viral groups on a global level, but also provides a snapshot of their prevalence patterns in Croatia in order to underscore the potential implications of viral seasonality. An overall global prevalence in respiratory tract infections was found to be between 0.5 and 18.4% for seasonal coronaviruses, between 13 and 59% for rhinoviruses, between 1 and 36% for human adenoviruses, and between 1 and 56.8% for human bocaviruses. A Croatian dataset on patients with respiratory tract infection and younger than 18 years of age has revealed a fairly high prevalence of rhinoviruses (33.4%), with much lower prevalence of adenoviruses (15.6%), seasonal coronaviruses (7.1%), and bocaviruses (5.3%). These insights represent a relevant discussion point in the context of the COVID-19 pandemic where the testing of non-SARS-CoV-2 viruses has been limited in many settings, making the monitoring of disease burden associated with other respiratory viruses rather difficult.