Molecular and clinical characterization of human adenovirus associated with acute respiratory tract infection in hospitalized children

Risk factors of severe conditions in hospitalized children with adenovirus infection and chest CT features

BACKGROUND

Children infected with human adenovirus (HAdV) were at particularly high risk of developing severe disease, but the risk factors of severe conditions are poorly understood.

OBJECTIVES

To explore the risk factors for developing into severe conditions in pediatric patients with HAdV infection by analyzing baseline epidemiological data, clinical characteristics, and computed tomography (CT) imaging features.

METHODS

In this retrospective study, 267 children with HAdV infection were included between October 2016 and September 2021 at Tongji Hospital, Wuhan, China. A descriptive analysis was conducted on the epidemiological and clinical data, as well as patient outcomes. CT manifestations were semi-quantitatively scored based on the presence of consolidation, ground-glass opacities, and emphysema in each lung lobe.

RESULTS

Our analysis revealed that there was a statistically significant difference in the rate of abnormalities observed on chest CT imaging (P = 0.007) and the imaging characteristics of chest CTs (P = 0.002) when comparing severe and mild cases. We found that co-infection with two or more additional pathogens occurred more frequently in severe cases. Additionally, the proportion of lymphocytes in laboratory tests was significantly lower in patients with severe conditions. Furthermore, both the proportions and scores of consolidations were markedly higher in each lung lobe among the severe cases.

CONCLUSIONS

Our findings may assist in identifying children hospitalized with HAdV who are at increased risk for severe conditions, thereby facilitating more aggressive treatment and care strategies.

Etiological analysis of acute respiratory infections in hospitalized children after the relaxation of COVID-19 non-pharmacological interventions in Quzhou, China

BACKGROUND

Acute respiratory infections (ARIs) can cause morbidity and mortality in children. This study was to determine the characteristics of pathogens in hospitalized children with ARIs after the relaxation of COVID-19 non-pharmacological interventions (NPIs) in Quzhou, China.

METHODS

Hospitalized children with ARIs were enrolled between May and October 2023, and thirteen common respiratory pathogens were tested by fluorescent quantitative polymerase chain reaction. Mono- and co-infections were assessed, and the association between pathogens and age was explored using restricted cubic spline analysis.

RESULTS

A total of 1225 children were included, 820 of them detected one pathogen and 238 of them detected two or more pathogens. The dominant pathogen varies monthly. Mycoplasma pneumoniae (Mp) was the most common pathogen in monoinfection, followed by respiratory syncytial virus (RSV) and human rhinovirus (HRV), while influenza virus was detected at a lower rate. Mp + HRV was the most common combination of coinfections. The detection rates of Mp and HRV were higher in coinfections than in monoinfection, but there was no difference in the detection rate of RSV. Children aged 1-3 years had the highest positive detection rates and were more likely to be infected with multiple pathogens, with 40% of respiratory pathogen monoinfection and 47.48% of coinfections (χ2 = 4.245, P = 0.039). In the restricted cubic spline models, a J-shaped association was consistently observed between age and Mp infection, the risk of HRV first increased and then decreased, the risk of RSV was relatively flat until 1.5 years and then decreased rapidly.

CONCLUSION

Our study revealed the epidemiological characteristics of ARIs pathogens after the relaxation of NPIs. The positivity rates of Mp, RSV, and HRV are the highest, while those of influenza virus are still low. Additionally, age and season affect the distribution of respiratory pathogens. These findings underscore the importance of ongoing regional pathogen surveillance to guide local public health responses.

Mutations at the conserved N-Terminal of the human Rhinovirus capsid gene VP4, and their impact on the immune response

Rhinoviruses (RV) are the major cause of chronic obstructive pulmonary disease and are associated with exacerbation development as well as community-acquired pneumonia in children, leading to substantial morbidity, mortality, and hospital admission. Here we have examined how changes at the amino terminal of the conserved VP4 epitope of different RV serotypes may affect pulmonary cytokine and chemokine responses and disease severity. Samples positive for rhinovirus were used for genetic characterization, followed by profiling gene expression of pulmonary Th1 and Th2 cytokines/chemokines by RT-PCR arrays. Genetic sequencing and homology 3D modeling revealed changes at the amino terminal of the conserved viral protein 4 (VP4) epitope in the RV-A101 serotype, especially serine at several positions that are important for interactive binding with the host immune cells. We found dysregulation of pulmonary gene expression of Th1- and Th2-related cytokines and chemokines in RV-A 101 and RV-C 8 pneumonia patients. These findings might contribute to a better understanding of RV immunity and the potential mechanisms underlying the pathogenesis of severe RV infections, but further functional studies are needed to confirm the causal relationship.

Genetic Diversity of the Human Adenovirus C Isolated from Hospitalized Children in Russia (2019-2022)

The human adenovirus (HAdV) is a common pathogen in children that can cause acute respiratory virus infection (ARVI). However, the molecular epidemiological and clinical information relating to HAdV among hospitalized children with ARVI is rarely reported in Russia. A 4-year longitudinal (2019-2022) study among hospitalized children (0-17 years old) with ARVI in Novosibirsk, Russia, was conducted to evaluate the epidemiological and molecular characteristics of HAdV. Statistically significant differences in the detection rates of epidemiological and virological data of all positive viral detections of HAdV were analyzed using a two-tailed Chi-square test. The incidence of HAdV and other respiratory viruses such as human influenza A and B viruses, respiratory syncytial virus, coronavirus, parainfluenza virus, metapneumovirus, rhinovirus, bocavirus, and SARS-CoV-2 was investigated among 3190 hospitalized children using real-time polymerase chain reaction. At least one of these respiratory viruses was detected in 74.4% of hospitalized cases, among which HAdV accounted for 4%. A total of 1.3% co-infections with HAdV were also registered. We obtained full-genome sequences of 12 HAdVs, which were isolated in cell cultures. Genetic analysis revealed the circulation of adenovirus of genotypes C1, C2, C5, C89, and 108 among hospitalized children in the period from 2019-2022.

Clinical Characteristics and Genotyping of Pediatric Adenovirus Pneumonia Disease and Coinfection in Southeast China

Introduction: Human adenovirus (HAdV) is a common pathogen that can cause acute respiratory infections (ARIs) in children. Adenovirus pneumonia is the most severe respiratory disease associated with HAdV. Objective: We aimed to investigate the clinical characteristics of children hospitalized with adenovirus pneumonia in Quanzhou, China, in 2019. We also sought to determine the viral genotype in these cases and explore cases associated with severe adenovirus pneumonia. Methods: We collected oropharyngeal swabs from 99 children who were hospitalized with pneumonia in Quanzhou Women and Children's Hospital, these samples were tested for the presence of HAdV. Genotyping of the viruses was performed by real-time polymerase chain reaction. Logistic regression analysis was employed to analyze risk factors related to severe adenovirus pneumonia. The epidemiological data were examined using the Statistical Package for Social Sciences software (SPSS). Results: Among the 99 patients in our study, the median age was 21 months. We observed a 4% mortality rate among those diagnosed with adenovirus pneumonia. Adenovirus pneumonia often presents as a coinfection. Lactate dehydrogenase and neutrophil percentages of WBC's were significantly increased in patients with severe adenovirus pneumonia compared with mild HAdV disease. The predominant viral genotypes identified were type 3 and type 7. Conclusions: In the Quanzhou area of southeast China, the incidence of adenovirus pneumonia was found to be high among children younger than two years old. Type 7 HAdV was identified as the primary pathogen. A long duration of fever, dyspnea and digestive system complications were risk factors for severe adenovirus pneumonia after HAdV infection. Clinical Trial Registration number: ChiCTR2200062358.

Molecular epidemiology and phylogenetic analyses of human adenovirus in pediatric patients with acute respiratory infections from Hangzhou during COVID-19 pandemic

Background

Acute Respiratory Infections (ARIs) are a major cause of morbidity and mortality worldwide. Human Adenovirus (HAdV), responsible for 5%-10% of children's ARIs, is one of the most prevalent pathogens. Our study aimed to analyze the epidemiology and phylogenesis of HAdV in pediatric patients with ARIs in Hangzhou during the COVID-19 pandemic.

Method

Between November 2020 and March 2021, we collected 1,442 nasopharyngeal swabs from children with ARIs at Children's Hospital, Zhejiang University School of Medicine. Epidemiological statistics, phylogenetic and amino acid (AA) mutation analysis were conducted.

Results

Our findings revealed that 386 (26.77%) samples tested positive for HAdV, with the highest rate in children aged 6-18 years and the lowest in children aged 0-1 year, indicating a different age preference of HAdV compared with pre-pandemic period. Outpatients had a significantly higher positive rate than inpatients. Moreover, patients with HAdV-coinfection exhibited more severe clinical symptoms than those with HAdV-single infection. Our phylogenetic analysis demonstrated that species HAdV-C (type 1, 2, 6) were the predominant circulating strains in Hangzhou during the COVID-19 pandemic. Further AA mutation analysis identified seventeen mutations of particular concern for biological characterization.

Conclusion

In conclusion, our study provides valuable epidemiological and molecular data that will aid in epidemiological surveillance, antiviral therapies and the development of specific vaccine types, leading to improve public health.

Pneumonia in Children During the 2019 Outbreak in Xiamen, China

BACKGROUND

To understand the regional epidemiology and clinical characteristics of adenovirus pneumonia in hospitalized children during the 2019 outbreak of respiratory adenoviruses in China.

METHODS

We analyzed the epidemiologic trend of adenovirus in children hospitalized for acute lower respiratory tract infections in Xiamen in 2019. Adenovirus was identified using direct fluorescent antibody detection. During the peak seasons of adenovirus epidemic, 170 adenovirus-positive specimens were obtained for molecular typing, and the clinical data were collected.

RESULTS

Among the 9890 children hospitalized for acute lower respiratory tract infection, 609 (6.2%) were tested positive for adenovirus. The detection rate of adenovirus was significantly higher in boys than in grils (9.5% vs. 4.6%, P < 0.05). Adenovirus activity increased markedly between April and August with the prevalence of 7.3%-12.4%. During the outbreak season, type 7 accounted for 70.6%, followed by type 3 (28.8%) and type 4 (0.6%). Of the 155 cases of adenovirus pneumonia, the median age was 3.0 years (range: 4 month to 9 years), 153 (98.7%) had fever with a mean fever duration of 9.04 ± 5.52 days, 28 (16.5%) had wheezing, 93 (60%) showed segmental or lobar consolidation with atelectasis and 13 (8.4%) showed pleural effusion. Forty-six (29.6%) cases developed severe pneumonia, 7 (4.1%) required mechanical ventilation and 2 (1.2%) died. Younger age, longer duration of fever and higher fever spike were more frequently seen in severe cases (P < 0.05). Twenty-five (16.2%) had C-reactive protein ≥ 40 mg/L, and 91 (58.7%) had procalcitonin ≥ 0.25 mg/L.

CONCLUSIONS

Adenovirus types 7 and 3 caused the outbreak of adenovirus pneumonia in community children during late spring to summer in 2019 in Xiamen. The majority of adenovirus pneumonia resembles bacterial pneumonia. The incidence of severe pneumonia was high when type 7 predominantly prevailed. Adenovirus type 7 was more common in severe cases than in nonsevere cases.

Molecular epidemiology of human adenoviruses in children with and without respiratory symptoms: Preliminary findings from a case-control study

Background

Human adenovirus (HAdV) is an important viral agent in children which can lead to severe acute respiratory infection (SARI). Reports on molecular epidemiology of HAdVs in Iran are limited. This case-control study is conducted to compare the HAdV infection rate and molecular epidemiology among two groups of children with and without respiratory symptoms in Tehran, Iran during 2018–2019.

Methods

Nested PCR was performed on 120 oropharyngeal swabs taken from children aged five and younger with SARI who were hospitalized as the case group, and 120 oropharyngeal swabs were collected from children of the same age without respiratory symptoms as the control group. For positive samples Sanger sequencing was done and a phylogenetic tree was drawn afterward.

Results

Out of 120 cases, 8 (6.6%) tested positive for eachHAdV types including 6 (75%) HAdV-B7, 1 (12.5%) HAdV-C2, and 1 (12.5%) HAdV-C6. Among the control group, out of 120 samples, 8 (6.6%) were positive comprising 5 (62.5%) HAdV-C5, 2 (25%) HAdV-F41, and 1 (12.5%) HAdV-C6.

Conclusion

The present study indicated a different viewpoint of HAdV molecular epidemiology in which the genotypes were compared in children with and without respiratory symptoms. HAdV prevalence was equally common in cases and controls but different genotypes were detected in these two groups. HAdV-B7 was the main type among children with SARI, dissimilar to children with no respiratory symptoms where HAdV-C5 was the predominant type. Detecting HAdV-F in oropharyngeal swabs was a rare finding, which requires further investigation.

Effects of perinatal disease activity on offspring's growth in patients with systemic lupus erythematosus

Introduction

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disorder with a variable clinical course, ranging from mild to severe forms. It mainly occurs in women, especially those of fertile age. The aim of the study was to systematically analyze the associations of perinatal disease activity with adverse outcomes of Chinese patients with SLE and their offspring.

Material and methods

Data of prenatal SLE patients and healthy pregnant woman admitted to our hospital during the period October 2001 to January 2018 were retrospectively collected, and the status of offspring of SLE patients was followed up in March 2020. Disease activity was evaluated by SLE disease activity index 2000 (SLEDAI-2k), and those with scores > 6 were defined as having active disease.

Results

In total, 198 deliveries of 194 SLE patients and 199 deliveries of healthy women were documented. Maternal and fetal adverse outcomes occurred in 74 (37.4%) and 90 (45.5%) deliveries of SLE patients, respectively, which were significantly higher than those of healthy subjects. Among SLE patients, the active group had higher rates of gestational hypertension (p < 0.001), preeclampsia/eclampsia (p < 0.001), low birth weight (p < 0.001), premature birth (p < 0.001) and fetal growth restriction (FGR) (p < 0.01) than the inactive group. Multivariate logistic analysis revealed that perinatal renal activity was associated with gestational hypertension (OR = 4.43, p < 0.001), preeclampsia/ eclampsia (OR = 9.14, p < 0.001), low birth weight (OR = 2.24, p < 0.05) and premature birth (OR = 4.20, p < 0.001). Compared with the general population, offspring of SLE patients had relatively high rates of eczema (50/142, 35.2%) and congenital heart disease (6/142, 4.2%), which were irrelevant to perinatal disease activity, but related to specific antibodies.

Conclusions

For perinatal women with SLE, renal activity is associated with a variety of adverse pregnancy outcomes. However, maternal perinatal disease activity does not seem to affect the growth of their offspring.

Human Mastadenovirus Infections in Children: A Review of the Current Status in the Arab World in the Middle East and North Africa

Human mastadenovirus (HAdV) is a non-enveloped icosahedral virus with double-stranded DNA genomes. The mortality rate of HAdV infections can reach 35.5%, while gastroenteritis HAdV infections, HAdV pneumonia, and disseminated disease tend to show a worse outcome, with rates ranging from 44.2% to 50%. In addition, HAdV can cause infections at any age but most commonly in the pediatric population, especially in young children and infants. Therefore, this review aims to assess the current status of HAdV infections among children in the Arab World, particularly in the Middle East and North Africa. Web of Science, Scopus, PubMed, EMBASE, and Google Scholar databases for publications in English were searched up to July 2022 for relevant articles. The literature search yielded a total of 21 studies, which were included in this review. Studies reporting HAdV infections in children were conducted in 17 out of the 22 countries. The average prevalence rate of HAdV infections in children was 12.7%, with average prevalence rates of 12.82% and 12.58% in the Middle East and North African countries, respectively. The highest prevalence rate (28.3%) was reported in Egypt, whereas the lowest prevalence (1.5%) was reported in Sudan. The included studies presented children with signs and symptoms of gastroenteritis, acute respiratory infection, acute diarrhea, and acute hemorrhagic conjunctivitis. In conclusion, the average prevalence rate of HAdV infections in children was 12.7%, with average prevalence rates of 12.82% and 12.58% in the Middle East and North African countries, respectively. Finding the precise prevalence rate of this virus is crucial because it will guide future planning for effective disease control and the selection of particular treatment options during epidemics and special seasons.

Molecular typing and epidemiology profiles of human adenovirus infection among hospitalized patients with severe acute respiratory infection in Huzhou, China

Background

Severe acute respiratory infections (SARI) threaten human health and cause a large number of hospitalizations every year. However, as one of the most common pathogen that cause acute respiratory tract infection, the molecular epidemiological information relating to human adenoviruses (HAdVs) among patients with SARI is limited. Here, we evaluate the epidemiological and molecular characteristics of HAdV infections among hospitalized patients with SARI from January 2017 to December 2019 in Huzhou, China.

Methods

From January 2017 to December 2019, a total of 657 nasopharyngeal swabs collected from inpatients with SARI were screened for HAdV and other common respiratory viruses by multiplex real-time PCR. All samples that tested positive for HAdV were further typed by sequencing partial sequences of hexon gene. Genotypes of HAdV were confirmed by phylogenetic analysis. Epidemiological data were analyzed using Microsoft Excel 2010 and service solutions (SPSS) 21.0 software.

Results

251 (38.20%) samples were positive for at least one respiratory virus. HAdV was the second common viral pathogen detected, with a detection rate of 7.08%. Infection with HAdV was found in all age groups tested (0<2, 2<5, 5<15, 15<50, 50<65, ≥65). Children under 15 years old accounted for 84.62% (44/52) of the infections. Higher activity of HAdV infection could be seen in spring-early autumn season. Seven different types of HAdV belonging to 4 species (HAdV-A, B, C, E) were identified in hospitalized SARI cases, with HAdV-B3 as the most prevalent HAdV types, followed by HAdV-B7 and HAdV-E4. HAdV-B3 was the most frequently detected genotype in 2017 and 2019, accounting for 75.00% (9/12) and 63.64% (7/11) of typed HAdV infections in 2017 and 2019, respectively. No predominant strain was responsible for HAdV infections in 2018, although HAdV-B7 (28.57%, 2/7) and HAdV-C1 (28.57%, 2/7) were the major causative genotypes.

Conclusions

This study revealed the prevalence and the molecular epidemiological characteristics of HAdV infections among hospitalized patients with SARI in Huzhou from January 2017 to December 2019. The HAdV prevalence is related to age and season. As the most prevalent HAdV types, HAdV-B3 was co-circulating with other types and presented an alternate prevalence pattern.

Human adenoviruses in paediatric patients with respiratory tract infections in Beijing, China

Background

Human adenoviruse (HAdV) is a major pathogen of paediatric respiratory tract infections (RTIs). Mutation or recombination of HAdV genes may cause changes in its pathogenicity and transmission. We described the epidemiology and genotypic diversity of HAdV in hospitalized children with RTIs in Beijing, China.

Methods

Nasopharyngeal aspirates were collected from hospitalized children with RTIs from April 2018 to March 2019. HAdVs were detected by a quantitative real-time PCR, and the hexon gene was used for phylogenetic analysis.

Results

Among 1572 samples, 90 (5.72%) were HAdV-positive. The HAdV detection rate was highest in November and July. Among HAdV-positive children, 61.11% (55/90) were co-infected with other respiratory viruses, the most common of which were human respiratory syncytial virus and human rhinovirus. The main diagnosis was bronchopneumonia, most patient have cough and fever. Children with a high viral load were more likely to have a high fever (P = 0.041) and elevated WBC count (P = 0.000). Of 55 HAdV-positive specimens, HAdV-B (63.64%), HAdV-C (27.27%), and HAdV-E (9.09%) were main epidemic species. Phylogenetic analysis indicated that hexon sequences of three samples were on the same branch with the recombinant HAdV strain (CBJ113), which was circulating in Beijing since 2016.

Conclusion

The HAdV-B3 and HAdV-B7 are the main epidemic strains in Beijing, and the recombinant HAdV-C strain CBJ113 has formed an epidemic trend.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-021-01661-6.

Clinical and CT findings of adenovirus pneumonia in immunocompetent adults

INTRODUCTION

Adenovirus pneumonia is not uncommon in children and immunocompromised patients. However, the study of the clinical and computed tomography (CT) characteristics of Adenovirus pneumonia in immunocompetent adults is still limited.

OBJECTIVE

The objective of this study was to retrospectively observe the clinical and CT characteristics as well as their dynamic change of Adenovirus pneumonia in immunocompetent adults.

METHODS

Twenty patients (18 males, median age, 36 years old) with Adenovirus pneumonia were retrospectively included from January 2018 to December 2019. Clinical information and chest CT at admission of all patients were reviewed. Twelve patients underwent serial CT scans, and the temporal changes of CT findings were summarized. Pneumonia severity index (PSI) was calculated according to clinical information.

RESULTS

The median time interval from illness onset to admission was 6 days (interquartile range [IQR], 5-7.5 days). The clinical characteristics included the high fever (39.2 ± 0.8°C) with the normal white blood cell count, the decreased lymphocyte, and elevated C-reactive protein. Ten cases complicated with mycoplasma infection at admission. Thirteen patients were mechanically ventilated, and two patients died during hospitalization. Consolidation was a predominant pattern found during the first 2 weeks and then resolved to minimal consolidation after the fourth week. There was no significant correlation between CT score and PSI score (r = 0.15, p = 0.41).

CONCLUSIONS

Predominant radiological finding of Adenovirus pneumonia was consolidation. Multilobular involvement, higher CT scores, and pleural effusion were found in more severe patients. The abnormal opacity peaked in 2 weeks of illness onset and gradually resolved after the third week. The temporal changes of radiological score are consistent with clinical findings.

Development and Application of a Fast Method to Acquire the Accurate Whole-Genome Sequences of Human Adenoviruses

The whole-genome sequencing (WGS) of human adenoviruses (HAdVs) plays an important role in identifying, typing, and mutation analysis of HAdVs. Nowadays, three generations of sequencing have been developed. The accuracy of first-generation sequencing is up to 99.99%, whereas this technology relies on PCR and is time consuming; the next-generation sequencing (NGS) is expensive and not cost effective for determining a few special samples; and the third-generation sequencing technology has a higher error rate. In this study, first, we developed an efficient HAdV genomic DNA extraction method. Using the complete genomic DNA instead of the PCR amplicons as the direct sequencing template and a set of walking primers, we developed the HAdV WGS method based on first-generation sequencing. The HAdV whole genomes were effectively sequenced by a set of one-way sequencing primers designed, which reduced the sequencing time and cost. More importantly, high sequence accuracy is guaranteed. Four HAdV strains (GZ01, GZ02, HK35, and HK91) were isolated from children with acute respiratory diseases (ARDs), and the complete genomes were sequenced using this method. The accurate sequences of the whole inverted terminal repeats (ITRs) at both ends of the HAdV genomes were also acquired. The genome sequence of human adenovirus type 14 (HAdV-B14) strain GZ01 acquired by this method is identical to the sequence released in GenBank, which indicates that this novel sequencing method has high accuracy. The comparative genomic analysis identified that strain GZ02 isolated in September 2010 had the identical genomic sequence with the HAdV-B14 strain GZ01 (October 2010). Therefore, strain GZ02 is the first HAdV-B14 isolate emergent in China (September 2010; GenBank acc no. MW692349). The WGS of HAdV-C2 strain HK91 and HAdV-E4 strain HK35 isolated from children with acute respiratory disease in Hong Kong were also determined by this sequencing method. In conclusion, this WGS method is fast, accurate, and universal for common human adenovirus species B, C, and E. The sequencing strategy may also be applied to the WGS of the other DNA viruses.

Emergence and characterization of a putative novel human adenovirus recombinant HAdV-C104 causing pneumonia in Southern China

In 2017, a survey of the molecular epidemiology of human adenovirus (HAdV) infections in Southern China based on hexon and fiber genotype demonstrated that the most prevalent genotypes of HAdV were HAdV-3 (n = 62), HAdV-2 (n = 21), and HAdV-7 (n = 16). In addition, two patients were co-infected with two genotypes of HAdV. Interestingly, a novel human adenovirus C recombinant genotype strain was isolated from one of the pneumonia patients in this survey. Phylogenetic, recombination, and proteotyping analysis showed that this novel pathogen originated from the recombination of parental viruses harboring the HAdV-1 penton and hexon gene, and the HAdV-2 fiber gene. It was named ‘P1H1F2’ and was assigned as HAdV-C104 based on the nomenclature protocol of using three major capsid proteins for characterization. Subsequent in vitro experiments demonstrated that HAdV-C104 had comparable proliferation capacity to HAdV-1, HAdV-2, and another recombination genotype P1H2F2. In addition, the HAdV-C104 infected patient was diagnosed with pneumonia and recovered after antiviral therapy. This report strengthens the hypothesis of recombination as a major pathway for the molecular evolution of HAdV-C species.

The Epidemiology, Molecular, and Clinical of Human Adenoviruses in Children Hospitalized With Acute Respiratory Infections

Introduction

Human adenovirus (HAdV) is a common pathogen in children with acute respiratory infections (ARIs). The aim was to describe the epidemiology, molecular, and clinical characteristics of HAdV among children hospitalized with ARIs in Wenzhou in southeastern China.

Methodology

From January 2018 to December 2019, nasopharyngeal swab or sputum specimens were prospectively collected from hospitalized children with ARIs. HAdV was detected using direct immunofluorescence. We used a multiplex PCR assay combined with capillary electrophoresis targeting the hexon gene’s hypervariable region to identify HAdV types 1, 2, 3, 4, 5, 7, 14, 21, 37, 40, 41, and 55. We analyzed the epidemiological, molecular, and clinical data according to the HAdV type.

Results

HAdVs were detected in 1,059 (3.5%) of the total of 30,543 children tested. A total of 947 cases with monotype HAdV identified by the PCR assay were included in the analysis. HAdV-3 (415/947, 43.8%), HAdV-7 (318/947, 33.6%), HAdV-2 (108/947, 11.4%), and HAdV-1 (70/947, 7.4%) were the predominant types. Of the 550 (58.1%) cases detected from December 2018 to August 2019, HAdV-3, and HAdV-7 were the main types. The main diagnoses included 358 cases of pneumonia, 232 cases of tonsillitis, 198 cases of bronchitis, and 159 cases of upper respiratory tract infection (URTI). Among children with pneumonia the main types were HAdV-7 (51.1%), HAdV-3 (36.9%), and HAdV-1 (2.2%). Among children with bronchitis, the main types were HAdV-3 (48.0%), HAdV-7 (28.3%), and HAdV-2 (10.6%). Among children with URTIs, the main types were HAdV-3 (49.7%), HAdV-7 (22.6%), and HAdV-2 (13.2%). Among children with tonsillitis, the main types were HAdV-3 (47.4%), HAdV-2 (22.4%), and HAdV-7 (18.5%). In total, 101 (55.2%) patients required supplemental oxygen, 15 (8.2%) required critical care, and 1 child (0.5%) with HAdV-7 pneumonia died.

Conclusion

HAdV-3 -7, -2, and -1 were the predominant types identified in hospitalized children with ARIs in Wenzhou. From December 2018 to August 2019, there were outbreaks of HAdV-3 and -7. There were significant differences in HAdV types among children with pneumonia, tonsillitis, bronchitis, and URTI. HAdV-7 can cause more severe pneumonia in children than HAdV-3.

Functionalized Surfaces as a Tool for Virus Sensing: A Demonstration of Human mastadenovirus Detection in Environmental Waters

The main goal of this study was to apply magnetic bead surface functionalization in the form of immunomagnetic separation (IMS) combined with real-time polymerase chain reaction (qPCR) (IMS-qPCR) to detect Human mastadenovirus species C (HAdV-C) and F (HAdV-F) in water samples. The technique efficiency was compared to a nonfunctionalized method (ultracentrifugation) followed by laboratory detection. Tests were carried out to standardize IMS parameters followed by tests on 15 water samples concentrated by IMS and ultracentrifugation. Microscopic analyses detected a successful beads–antibody attachment. HAdV was detected up to dilutions of 10−6 by IMS-qPCR, and samples concentrated by IMS were able to infect cell cultures. In water samples, HAdV-C was detected in 60% (monoclonal) and 47% (polyclonal) by IMS-qPCR, while 13% of samples concentrated by ultracentrifugation gave a positive result. HAdV-F was positive in 27% of samples by IMS-qPCR (polyclonal) and ultracentrifugation and 20% by IMS-qPCR (monoclonal). The rate of detection varied from 4.55 × 102 to 5.83 × 106 genomic copies/L for IMS-qPCR and from 2.00 × 102 to 2.11 × 103 GC/L for ultracentrifugation. IMS showed to be a more effective concentration technique for HAdV than ultracentrifugation, improving the assessment of infectious HAdV in water resources.

Study of the Etiology of Acute Respiratory Infections in Children Under 5 Years at the Dr. Agostinho Neto Hospital, Praia, Santiago Island, Cabo Verde

Background: Acute respiratory infections are one of the major causes of morbidity and mortality in children under 5 years in developing countries and are a challenge for the health system of these countries. In Cabo Verde, despite the lack of recent studies, data indicate that it affects thousands of children, being the fourth leading cause of infant mortality in 2013. The aim of this study was to identify and describe the etiological agents associated with acute respiratory tract infections in children under 5 years old, and their associated risk factors, such as clinical symptoms or socio-demographic characteristics. Methods: Naso-pharyngeal samples were collected from children under 5 years attending at Dr. Agostinho Neto Hospital (Praia, Santiago Island, Cabo Verde) with suspected ARI at different time-points during 2019. Samples were analyzed using FilmArray® Respiratory Panel v. 2.0 Plus to identify etiological agents of ARI. A questionnaire with socio-demographic information was also collected for each participant. Data analyses were carried out using the IBM SPSS version 25 (IBM Corporation, Armonk, NY) and R 3.5.1 statistical software. Results: A total of 129 naso-pharyngeal samples were included in the study. Seventeen different etiologic agents of respiratory infections were identified. HRV/EV was the most frequent agent detected, followed by FluA H3 and RSV. Coinfection with two or more pathogens was detected in up to 20% of positive samples. The results were analyzed in terms of age-group, sex, period of the year and other social and demographic factors. Conclusion: Viruses are the main causative agents of ARI in children <5 years attending at the pediatrics service at the Dr. Agostinho Neto Hospital in Praia city, Santiago Island, Cabo Verde. Some factors are described in this study as statistically associated with the presence of an infectious agent, such as having one or more children sharing the bedroom with an adult and the presence of some clinical symptoms. The data addresses the need for studies on respiratory tract infections in Cabo Verde.