Viral etiology of acute febrile respiratory illnesses in hospitalized children younger than 24 months

Prevalence of Influenza Viruses A and B, Adenovirus, Respiratory Syncytial Virus, and Human Metapneumonia Viruses among Children with Acute Respiratory Tract Infection

Background

Acute respiratory tract infection (ARTI) is a significant cause of morbidity and mortality among children worldwide. The majority of acute respiratory infections in children are caused by viruses, with respiratory syncytial virus (RSV) being the most frequently encountered. Other important viral pathogens include human metapneumovirus, human coronaviruses, adenovirus, and influenza. These infections can lead to complications such as bronchitis and pneumonia. So, this study aimed to evaluate the prevalence of influenza viruses A and B, adenovirus, respiratory syncytial virus (RSV), and human metapneumovirus (HMPV) in children with ARTI.

Methods

The molecular diagnostic of polymerase chain reaction approach was used to detect influenza (A and B), metapneumovirus, respiratory syncytial virus (RSV), and adenovirus in respiratory samples of children with acute respiratory infection hospitalization in a teaching hospital of the Shiraz University of Medical Sciences in January 2016-March 2017.

Results

Of the 340 patients examined, 208 (61.20%) were male and the median age was 3.13 ± 2.38 years. Respiratory viruses were found in 179 (52.64%) patients. The male-to-female ratio was 1.63 : 1 in patients who were viral positive. Detection rates for influenza A, adenovirus, influenza B, RSV, and HMPV were 28.23%, 24.70%, 8.52%, 3.23%, and 2.64%, respectively, and coinfections were detected in 24.02%. The most common combination of two-virus coinfections was IFVA/AdV, followed by IFVB/AdV, AdV, IFVB/IFVA, RSV/IFVA, HMPV/AdV, RSV/AdV, and HMPV/IFVA.

Conclusion

The high prevalence of respiratory viruses in children hospitalized with ARTI suggests that viral infection may play a role in disease pathogenesis. This should be confirmed through the conduct of case-control studies and may inform the role of vaccination to prevent respiratory viral infections.

Systematic Literature Review of Respiratory Syncytial Virus Laboratory Testing Practices and Incidence in United States Infants and Children <5 Years of Age

Background

Respiratory syncytial virus (RSV) can cause serious illness in those aged <5 years in the United States, but uncertainty remains around which populations receive RSV testing. We conducted a systematic literature review of RSV testing patterns in studies published from 2000 to 2021.

Methods

Studies of RSV, medically attended RSV lower respiratory tract infections (LRTIs), and bronchiolitis were identified using standard methodology. Outcomes were clinical decisions to test for RSV, testing frequency, and testing incidence proportions in inpatient (IP), emergency department (ED), outpatient (OP), and urgent care settings.

Results

Eighty good-/fair-quality studies, which reported data from the period 1988–2020, were identified. Twenty-seven described the clinical decision to test, which varied across and within settings. Two studies reported RSV testing frequency for multiple settings, with higher testing proportions in IP (n = 2, range: 83%–85%, 1996–2009) compared with ED (n = 1, 25%, 2006–2009) and OP (n = 2, 15%–25%, 1996–2009). Higher RSV testing incidence proportions were observed among LRTI infant populations in the ED (n = 1, 74%, 2007–2008) and OP (n = 2, 54%–69%, 1995–2008). Incidence proportions in LRTI populations were not consistently higher in the IP setting (n = 13). Across studies and time, there was heterogeneity in RSV testing patterns, which may reflect varying detection methods, populations, locations, time periods, and healthcare settings.

Conclusions

Not all infants and children with LRTI are tested for RSV, highlighting underestimation of RSV burden across all settings.

Viral etiology of acute respiratory infections during 2014–16 in Riyadh, Saudi Arabia

Aim: Viral etiology of respiratory infections is not well understood in Saudi Arabia. This study was conceptualized to understand viral etiology in children with acute respiratory tract infections (ARTI) from Riyadh. Patients and methods: Respiratory viruses were detected by real-time PCR in nasopharyngeal aspirates or swab from 580 children aged ≤5 years. Results: Respiratory viruses were detected in 64% of the samples with 6% mixed viral infections. Respiratory syncytial virus, adenovirus, influenza, parainfluenza and human metapneumovirus infections accounted for 42, 20, 16, 12 and 10%, respectively. Maximum prevalence (37%) was among the lowest age group followed by 30% among the 7- to 12-month age group. Conclusion: The prevalence and determinants of viral etiology are in line with the previous report from the region. No major shift in the viral etiologies was observed in the 2-year study period.

Hospital utilization rates for influenza and RSV: a novel approach and critical assessment

BACKGROUND

Influenza and respiratory syncytial virus (RSV) contribute significantly to the burden of acute lower respiratory infection (ALRI) inpatient care, but heterogeneous coding practices and availability of inpatient data make it difficult to estimate global hospital utilization for either disease based on coded diagnoses alone.

METHODS

This study estimates rates of influenza and RSV hospitalization by calculating the proportion of ALRI due to influenza and RSV and applying this proportion to inpatient admissions with ALRI coded as primary diagnosis. Proportions of ALRI attributed to influenza and RSV were extracted from a meta-analysis of 360 total sources describing inpatient hospital admissions which were input to a Bayesian mixed effects model over age with random effects over location. Results of this model were applied to inpatient admission datasets for 44 countries to produce rates of hospital utilization for influenza and RSV respectively, and rates were compared to raw coded admissions for each disease.

RESULTS

For most age groups, these methods estimated a higher national admission rate than the rate of directly coded influenza or RSV admissions in the same inpatient sources. In many inpatient sources, International Classification of Disease (ICD) coding detail was insufficient to estimate RSV burden directly. The influenza inpatient burden estimates in older adults appear to be substantially underestimated using this method on primary diagnoses alone. Application of the mixed effects model reduced heterogeneity between countries in influenza and RSV which was biased by coding practices and between-country variation.

CONCLUSIONS

This new method presents the opportunity of estimating hospital utilization rates for influenza and RSV using a wide range of clinical databases. Estimates generally seem promising for influenza and RSV associated hospitalization, but influenza estimates from primary diagnosis seem highly underestimated among older adults. Considerable heterogeneity remains between countries in ALRI coding (i.e., primary vs non-primary cause), and in the age profile of proportion positive for influenza and RSV across studies. While this analysis is interesting because of its wide data utilization and applicability in locations without laboratory-confirmed admission data, understanding the sources of variability and data quality will be essential in future applications of these methods.

Medically Attended Outpatient Coronavirus Infections in Ecuadorean Children During the 20 Months Preceding Countrywide Lockdown Related to the SARS-CoV-2 Pandemic of 2020

BACKGROUND

Human coronaviruses (HCoVs) cause respiratory tract infections during childhood manifesting as common colds, bronchiolitis, croup and pneumonia. In temperate geographies, HCoV activity peaks between December and March. The epidemiology and manifestations of HCoV infections have not been previously reported from Ecuador.

METHODS

Children <5 years who presented with ≥2 symptoms consistent with an acute respiratory tract infection were eligible for enrollment. After obtaining informed consent, demographic data and details regarding the acute illness were recorded. Secretions collected with a nasopharyngeal swab underwent diagnostic testing using multiplex polymerase chain reaction.

RESULTS

A total of 850 subjects were enrolled. A total of 677 (80%) tested positive for at least 1 pathogen, including 49 (7.2%) who tested positive for ≥1 HCoV type. HCoV-NL63 was the most frequent type detected (39%), followed by HCoV-OC43 (27%), 229E (22%) and HKU1 (12%). Nearly all subjects who tested positive for HCoV had nasal congestion or secretions (47/49; 96%). The most frequent syndromic diagnosis was common cold (41%), followed by bronchiolitis (27%). We found no association between the infecting HCoV type and subject's syndromic diagnosis (P > 0.05) or anatomic location of infection (upper vs. lower respiratory tract; P > 0.05). The 2018-2019 peak HCoV activity occurred from October to November; the 2019-2020 peak occurred from January to February.

CONCLUSIONS

HCoVs were detected in ~7% of outpatient Ecuadorean children <5 years of age with symptoms of acute respiratory tract infection. The most frequently detected HCoV types, and the period of peak HCoV activity differed for the 2018-2019 and 2019-2020 seasons.

Systematic Review of the Respiratory Syncytial Virus (RSV) Prevalence, Genotype Distribution, and Seasonality in Children from the Middle East and North Africa (MENA) Region

Respiratory syncytial virus (RSV) is one of the most common viruses to infect children worldwide and is the leading cause of lower respiratory tract illness (LRI) in infants. This study aimed to conduct a systematic review by collecting and reviewing all the published knowledge about the epidemiology of RSV in the Middle East and North Africa (MENA) region. Therefore, we systematically searched four databases; Embase, Medline, Scopus, and Cochrane databases from 2001 to 2019 to collect all the information related to the RSV prevalence, genotype distribution, and seasonality in children in MENA region. Our search strategy identified 598 studies, of which 83 met our inclusion criteria, which cover the past 19 years (2000–2019). Odds ratio (OR) and confidence interval (CI) were calculated to measure the association between RSV prevalence, gender, and age distribution. An overall prevalence of 24.4% (n = 17,106/69,981) of respiratory infections was recorded for RSV. The highest RSV prevalence was reported in Jordan (64%, during 2006–2007) and Israel (56%, 2005–2006). RSV A subgroup was more prevalent (62.9%; OR = 2.9, 95%CI = 2.64–3.13) than RSV B. RSV was most prevalent in children who were less than 12 months old (68.6%; OR = 4.7, 95%CI = 2.6–8.6) and was higher in males (59.6%; OR = 2.17, 95%CI = 1.2–3.8) than in female infants. Finally, the highest prevalence was recorded during winter seasons in all countries, except for Pakistan. RSV prevalence in the MENA region is comparable with the global one (24.4% vs. 22%). This first comprehensive report about RSV prevalence in the MENA region and our data should be important to guide vaccine introduction decisions and future evaluation.

Human coronavirus OC43 and other respiratory viruses from acute respiratory infections of Egyptian children

Respiratory infections have a significant impact on health worldwide. Viruses are major causes of acute respiratory infections among children. Limited information regarding its prevalence in Egypt is available. This study investigated prevalence of 10 respiratory viruses; Adenovirus, influenza A, B, respiratory syncytial virus (RSV), Parainfluenza virus (PIV)type 1-4, enterovirus, and human coronavirus OC43 (HCoV-OC43) among children in Alexandria, Egypt presenting with acute lower respiratory tract infections.The study was conducted on children <14 years of age selected from ElShatby Pediatric Hospital, Alexandria University, Egypt. One hundred children presenting during winter season with influenza-like illness were eligible for the study. Oropharyngeal swabs were collected and subjected to viral RNA and DNA extraction followed by polymerase chain reaction.Viral infections were detected in 44% of cases. Adenovirus was the most common, it was found in 19% of the patients. Prevalence of PIV (3 and 4) and enterovirus was 7% each. Prevalence of RSV and HCoV-OC43 was 5% and 3% respectively. Two percentage were Influenza A positive and 1% positive for influenza B. Mixed viral infection was observed in 7%.To the best of our knowledge, this is the first report of the isolation of HCoV-OC43 from respiratory infections in Alexandria, Egypt.

Characteristics and Outcomes of Young Children Hospitalized With Laboratory-confirmed Influenza or Respiratory Syncytial Virus in Ontario, Canada, 2009-2014

BACKGROUND

Respiratory illnesses are a major contributor to pediatric hospitalizations, with influenza and respiratory syncytial virus (RSV) causing substantial morbidity and cost each season. We compared the characteristics and outcomes of children 0-59 months of age who were hospitalized with laboratory-confirmed influenza or RSV between 2009 and 2014 in Ontario, Canada.

METHODS

We included hospitalized children who were tested for influenza A, influenza B and RSV and were positive for a single virus. We characterized individuals by their demographics and healthcare utilization patterns and compared their hospital outcomes, in-hospital cost and postdischarge healthcare use by virus type and by presence of underlying comorbidities.

RESULTS

We identified and analyzed 7659 hospitalizations during which a specimen tested positive for influenza or RSV. Children with RSV were the youngest whereas children with influenza B were the oldest [median ages 6 months (interquartile range: 2-17 months) and 25 months (interquartile range: 10-45 months), respectively]. Complex chronic conditions were more prevalent among children with all influenza (sub)types than RSV (31%-34% versus 20%). In-hospital outcomes were similar by virus type, but in children with comorbidities, postdischarge outcomes varied. We observed no differences in in-hospital cost between viruses or by presence of comorbidities [overall median cost: $4150 Canadian dollars (interquartile range: $3710-$4948)].

CONCLUSIONS

Influenza and RSV account for large numbers of pediatric hospitalizations. RSV and influenza were similar in terms of severity and cost in hospitalized children. Influenza vaccination should be promoted in pregnant women and young children, and a vaccine against RSV would mitigate the high burden of RSV.

Demographic and seasonal characteristics of respiratory pathogens in neonates and infants aged 0 to 12 months in the Central-East region of Tunisia

BACKGROUND

This study aimed to characterize the epidemiology of pathogenic respiratory agents in patients aged 0 to 12 months and hospitalized for acute respiratory infections in Tunisia between 2013 and 2014.

METHODS

A total of 20 pathogens, including viruses, Mycoplasma pneumoniae, and Streptococcus pneumoniae, were detected using molecular sensitive assays, and their associations with the patient's demographic data and season were analyzed.

RESULTS

Viral infectious agents were found in 449 (87.2%) of 515 specimens. Dual and multiple infectious agents were detected in 31.4% and 18.6% of the samples, respectively. Viral infection was predominant in the pediatric environment (90.8%, P < 0.001), male patients (88.0%), and spring (93.8%). Rhinovirus was the most detected virus (51.8%) followed by respiratory syncytial virus A/B (34.4%), coronavirus group (18.5%), adenovirus (17.9%), and parainfluenza viruses 1-4 (10.9%). Respiratory Syncytial virus A/B was significantly associated with gender (38.0% male cases vs 28.3% female cases, P = 0.02). Infections by Adenovirus, Bocavirus, and Metapneumovirus A/B increased with increasing age of patients (predominated cases aged 6-12 months, P < 0.001). S. pneumoniae was detected in 30.9% of th tested samples. In 18.2% of the negative viral infections, only S. pneumoniae was identified.

CONCLUSION

A predominance of the rhinovirus infection was observed in this study. Coronavirus subtypes were described for the first time in Tunisia. The observed different pathogenic profiles across age groups could be helpful to avoid the misclassification of patients presenting with ARIs at the triage level when no standardized protocol is available. This study will provide clues for physicians informing decisions regarding preventive strategies and medication in Tunisia.

Epidemiology and clinical characteristics of human coronaviruses OC43, 229E, NL63, and HKU1: a study of hospitalized children with acute respiratory tract infection in Guangzhou, China

Human coronaviruses (HCoV) OC43, 229E, NL63, and HKU1 are common respiratory viruses which cause various respiratory diseases, including pneumonia. There is a paucity of evidence on the epidemiology and clinical manifestations of these four HCoV strains worldwide. We collected 11,399 throat swabs from hospitalized children with acute respiratory tract infection from July 2009 to June 2016 in Guangzhou, China. These were tested for four strains of HCoV infection using real-time polymerase chain reaction (PCR). HCoV-positive patients were then tested for 11 other respiratory pathogens. 4.3% (489/11399) of patients were positive for HCoV, of which 3.0% were positive for OC43 (346/11399), 0.6% for 229E (65/11399), 0.5% for NL63 (60/11399), and 0.3% for HKU1 (38/11399). Patients aged 7–12 months had the highest prevalence of HCoV and OC43 when compared with other age groups (p < 0.001). The peak seasons of infection varied depending on the HCoV strain. Patients infected with a single strain of HCoV infection were less likely to present fever (≥ 38 °C) (p = 0.014) and more likely to present pulmonary rales (p = 0.043) than those co-infected with more than one HCoV strain or other respiratory pathogens. There were also significant differences in the prevalence of certain symptoms, including coughing (p = 0.032), pneumonia (p = 0.026), and abnormal pulmonary rales (p = 0.002) according to the strain of HCoV detected. This retrospective study of the prevalence of four HCoV strains and clinical signs among a large population of pediatric patients in a subtropical region of China provides further insight into the epidemiology and clinical features of HCoV.

Respiratory Tract Viral Infections and Coinfections Identified by Anyplex™ II RV16 Detection Kit in Pediatric Patients at a Riyadh Tertiary Care Hospital

Respiratory infections are caused by an array of viruses, and limited information is available about viral coexistence, comparative symptoms, and the burden of illness. This retrospective cohort study aimed to determine the etiological agents responsible for respiratory tract infections by Anyplex II RV16 detection kit (RV16, Seegene), involving 2266 pediatric patients with respiratory infections admitted to the Department of Pediatrics at King Abdul-Aziz Medical City, Ministry of National Guard, Riyadh, from July 2014 to June 2015. The most frequent respiratory infections were recorded in the 1 to 5 year age group (44.7%). Rhinovirus (32.5%), Adenovirus (16.9%), and Respiratory syncytial virus (RSV) B (10.4%) were most common. In single viral infections, Rhinovirus (41.2%), Metapneumovirus (15.3%), and Bocavirus (13.7%) were most frequent. In multiple viral infections, Rhinovirus (36.7%), Adenovirus (35.2%), Bocavirus (11.2), RSV B (7.8%), and RSV A (6.7%) were most frequent. No significant difference was observed in clinical presentations; however, rhinorrhea and hypodynamia were significantly associated with viral respiratory infections. Most respiratory viral pathogens peaked during December, January, March, and April. Rhinovirus, Adenovirus, and Bocavirus circulations were detected throughout the year. Winter peaks were recorded for Rhinovirus, RSV B, Adenovirus, and RSV A, whereas the Metapneumovirus, and the Bocavirus peaked in March and April. These findings enhance understanding of viral etiology and distribution to improve respiratory infection management and treatment.

Short-term relevance of lower respiratory viral coinfection in inpatients under 2 years of age

Introduction

Advances in molecular diagnosis have made it possible to detect previously unknown viral agents as causative agents of lower respiratory tract infections (LRTI). The frequency and relevance of viral coinfections is still debatable.

Objective

Compare clinical presentation and severity between single virus infection and viral coinfection in children admitted for LRTI.

Methods

A 3-year period observational study (2012–2015) included children younger than two years admitted for LRTI. Viral identification was performed using PCR technique for 16 viruses. Clinical data and use of health resources was gathered during hospital stay using a standard collection form and we compared single virus infection and viral coinfections.

Results

The study included 524 samples (451 patients); 448 (85.5%) had at least one virus identified. Viral coinfections were found in 159 (35.5%). RSV and HRV were the most commonly identified virus; bronchiolitis and pneumonia the most frequent diagnosis. Patients with viral coinfections were older, attended day-care centers, had previous recurrent wheezing more frequently and were more symptomatic at admission. These patients did not have more complementary exams performed but were prescribed medications more often. Viral coinfection group did not show longer length of hospital stay and oxygen need, more need for ICU nor ventilatory support.

Discussion

Our study showed a significant proportion of viral coinfections in young infants admitted with LRTI and confirmed previous data showing that prescription was more frequent in inpatients with viral coinfections, without an association with worst clinical outcome.

Respiratory virus detection during hospitalisation for lower respiratory tract infection in children under 2 years in South Auckland, New Zealand

AIM

To describe respiratory virus detection in children under 2 years of age in a population admitted with lower respiratory infection and to assess correlation with measures of severity.

METHODS

Nasopharyngeal aspirates from infants admitted with lower respiratory tract infection (n = 1645) over a 3-year time period were tested by polymerase chain reaction. We collected epidemiological and clinical data on all children. We assessed the correlation of presence of virus with length of hospital stay, intensive care admission and consolidation on chest X-ray.

RESULTS

Of the children admitted 34% were Maori, 43% Pacific and 75% lived in areas in the bottom quintile for socio-economic deprivation. A virus was found in 94% of those tested including 30% with multiple viruses. Picornavirus was present in 59% including 34% as the sole virus. Respiratory syncytial virus was found in 39%. Virus co-detection was not associated with length of stay, chest X-ray changes or intensive care unit admission.

CONCLUSION

In this disadvantaged predominately Maori and Pacific population, picornavirus is commonly found as a sole virus, respiratory syncytial virus is frequent but immunisation preventable influenza is infrequent. We did not find that co-detection of viruses was linked to severity.

[Short-term relevance of lower respiratory viral coinfection in inpatients under 2 years of age]

INTRODUCTION

Advances in molecular diagnosis have made it possible to detect previously unknown viral agents as causative agents of lower respiratory tract infections (LRTI). The frequency and relevance of viral coinfections is still debatable.

OBJECTIVE

compare clinical presentation and severity between single virus infection and viral coinfection in children admitted for LRTI.

METHODS

A 3-year period observational study (2012-2015) included children younger than two years admitted for LRTI. Viral identification was performed using PCR technique for 16 viruses. Clinical data and use of health resources was gathered during hospital stay using a standard collection form and we compared single virus infection and viral coinfections.

RESULTS

The study included 524 samples (451 patients); 448 (85,5%) had at least one virus identified. Viral coinfections were found in 159 (35,5%). RSV and HRV were the most commonly identified virus; bronchiolitis and pneumonia the most frequent diagnosis. Patients with viral coinfections were older, attended day-care centers, had previous recurrent wheezing more frequently and were more symptomatic at admission. These patients did not have more complementary exams performed but were prescribed medications more often. Viral coinfection group did not show longer length of hospital stay and oxygen need, more need for ICU nor ventilatory support.

DISCUSSION

Our study showed a significant proportion of viral coinfections in young infants admitted with LRTI and confirmed previous data showing that prescription was more frequent in inpatients with viral coinfections, without an association with worst clinical outcome.

Respiratory viral coinfection and disease severity in children: A systematic review and meta-analysis

•

Respiratory viral coinfections are common in children.

•

Overall pediatric respiratory viral coinfections have no impact on severity.

•

Prognostic role of specific viral interactions remains unclear.

Background

With advent of molecular diagnostic technologies, studies have reported detection of two or more respiratory viruses in about 30% of children with respiratory infections. However, prognostic role of coinfection remains unclear.

Objective

Evaluate relation between respiratory viral confection and illness severity in children.

Study design

MEDLINE (through PUBMED), EMBASE, EBSCO, LILACS databases were searched up to March 2015 by two independent reviewers. Studies assessing severity of viral coinfection in patients aged less than 18 years were included. Standardized forms were used for data extraction of population, study design, clinical syndromes, virus combinations compared and severity outcomes. Risk of bias and quality of evidence were assessed through EPHPP and GRADE. Subgroup analysis was performed according to age and viral combinations.

Results

Of 5218 records screened, 43 were included in analysis. Viral coinfection did not influence risks of all outcomes assessed: length of stay (mean difference in days in coinfection, −0.10 [95% confidence interval: −0.51 to 0.31]), length of supplemental oxygen (−0.42 [−1.05 to 0.20]), need of hospitalization (odds ratio of coinfection, 0.96 [95% confidence interval: 0.61–1.51]), supplemental oxygen (0.94 [0.66 to 1.34]), need of intensive care (0.99 [0.64 to 1.54]), mechanical ventilation (0.81 [0.33 to 2.01]) and death (2.22 [0.83 to 5.95]). Sub-analyses according to age and viral combinations have not shown influence of these factors in outcomes.

Conclusions

Respiratory viral coinfection did not increase severity in all outcomes assessed. Further studies are necessary to confirm this finding, especially regarding role of specific viral interactions.

Does Viral Co-Infection Influence the Severity of Acute Respiratory Infection in Children?

Background

Multiple viruses are often detected in children with respiratory infection but the significance of co-infection in pathogenesis, severity and outcome is unclear.

Objectives

To correlate the presence of viral co-infection with clinical phenotype in children admitted with acute respiratory infections (ARI).

Methods

We collected detailed clinical information on severity for children admitted with ARI as part of a Spanish prospective multicenter study (GENDRES network) between 2011–2013. A nested polymerase chain reaction (PCR) approach was used to detect respiratory viruses in respiratory secretions. Findings were compared to an independent cohort collected in the UK.

Results

204 children were recruited in the main cohort and 97 in the replication cohort. The number of detected viruses did not correlate with any markers of severity. However, bacterial superinfection was associated with increased severity (OR: 4.356; P-value = 0.005), PICU admission (OR: 3.342; P-value = 0.006), higher clinical score (1.988; P-value = 0.002) respiratory support requirement (OR: 7.484; P-value < 0.001) and longer hospital length of stay (OR: 1.468; P-value < 0.001). In addition, pneumococcal vaccination was found to be a protective factor in terms of degree of respiratory distress (OR: 2.917; P-value = 0.035), PICU admission (OR: 0.301; P-value = 0.011), lower clinical score (-1.499; P-value = 0.021) respiratory support requirement (OR: 0.324; P-value = 0.016) and oxygen necessity (OR: 0.328; P-value = 0.001). All these findings were replicated in the UK cohort.

Conclusion

The presence of more than one virus in hospitalized children with ARI is very frequent but it does not seem to have a major clinical impact in terms of severity. However bacterial superinfection increases the severity of the disease course. On the contrary, pneumococcal vaccination plays a protective role.

Systematic review and meta-analysis of respiratory viral coinfections in children

Respiratory infections are a common cause of paediatric morbidity. Clinical outcomes in children hospitalized with single respiratory virus infection are compared with those with two or more viral-viral coinfection. Studies were restricted to those reporting on children aged less than 5 years (PROSPERO CRD#42014009133). Published data to calculate risk ratios (RR) comparing children with single viral infections to coinfection using a random effects model were used. Similar analyses by pathogen pairs and by excluding children with comorbidities were performed. Of 4443 articles reviewed, 19 were included. Overall, no differences in the risk of fever, admission to an intensive care unit (ICU), oxygen use, mechanical ventilation and abnormal radiographs between children with single infection and those with coinfection were found. When analysing only children without comorbidities, the risk of fever (RR = 1.16 to RR = 1.24, 95% confidence intervals (CI) = 1.00-1.55) and ICU admission (RR = 1.08 to RR = 1.31, 95% CI = 0.93-1.83) increased but remained non-significant. Point estimates suggested an increased risk of ICU admission in those coinfected with either respiratory syncytial virus or human metapneumovirus compared with those with single infection but was non-significant. Our findings suggest that coinfection is not associated with increased clinical severity, but further investigations by pathogen pairs are warranted.

Detection of viral acute lower respiratory tract infection in hospitalized infants using real-time PCR

Introduction

Acute lower respiratory tract infection in children causes significant morbidity in the developing countries. Documentation of virus infection using PCR and clinical characteristics of patients affected with viral pneumonia are reviewed in this study.

Methods

51 children less than three years admitted to the Pediatric Hospital, Cairo University with viral pneumonia were included. All patients had undergone nasopharyngeal aspirate for PCR viral detection.

Results

A total of 51 cases were enrolled in the study, of which 7 cases were negative while 44 children were positive for viruses. The most common respiratory virus was Rhinovirus in 32 patients (72.2%), then parainfluenza virus (PIV) in 12 (27.3%), of which subtypes PIV1 were 2 (4.5%), PIV3 were 5 (11.4%) and PIV4 were 5 (11.4%) cases. The third common viruses were respiratory syncytial virus (RSV) in 9 (20.5%) cases of which 3 (6.8%) were RSVA and 6 (13.6%) were RSVB and adenovirus in 9 cases (20.5%). Boca virus was found in 8 (18.2%) patients, corona virus 2 (4.5%) patients, H1N1 2 (4.5%) patients, enterovirus 2 patients (4.5%) and human metapneumovirus in one case (2.3%). Influenza B and PIV2 were not detected. Coinfection was found in 28 (63.7%). Mortality occurred in 12 (23.5%). There was no significant relation between virus type or coinfection with disease severity.

Conclusions

RV was the most commonly detected virus in children under 3 years admitted with acute lower respiratory tract infections. Coinfection was present in the majority of our patients; however it was not related significantly to parameters of disease severity.

Viral Co-Infections in Pediatric Patients Hospitalized with Lower Tract Acute Respiratory Infections

BACKGROUND

Molecular techniques can often reveal a broader range of pathogens in respiratory infections. We aim to investigate the prevalence and age pattern of viral co-infection in children hospitalized with lower tract acute respiratory infection (LT-ARI), using molecular techniques.

METHODS

A nested polymerase chain reaction approach was used to detect Influenza (A, B), metapneumovirus, respiratory syncytial virus (RSV), parainfluenza (1-4), rhinovirus, adenovirus (A-F), bocavirus and coronaviruses (NL63, 229E, OC43) in respiratory samples of children with acute respiratory infection prospectively admitted to any of the GENDRES network hospitals between 2011-2013. The results were corroborated in an independent cohort collected in the UK.

RESULTS

A total of 204 and 97 nasopharyngeal samples were collected in the GENDRES and UK cohorts, respectively. In both cohorts, RSV was the most frequent pathogen (52.9% and 36.1% of the cohorts, respectively). Co-infection with multiple viruses was found in 92 samples (45.1%) and 29 samples (29.9%), respectively; this was most frequent in the 12-24 months age group. The most frequently observed co-infection patterns were RSV-Rhinovirus (23 patients, 11.3%, GENDRES cohort) and RSV-bocavirus / bocavirus-influenza (5 patients, 5.2%, UK cohort).

CONCLUSION

The presence of more than one virus in pediatric patients admitted to hospital with LT-ARI is very frequent and seems to peak at 12-24 months of age. The clinical significance of these findings is unclear but should warrant further analysis.

Viral coinfection in childhood respiratory tract infections

INTRODUCTION

The introduction of molecular techniques has enabled better understanding of the etiology of respiratory tract infections in children. The objective of the study was to analyze viral coinfection and its relationship to clinical severity.

METHODS

Hospitalized pediatric patients with a clinical diagnosis of respiratory infection were studied during the period between 2009-2010. Clinical and epidemiological data, duration of hospitalization, need for oxygen therapy, bacterial coinfection and need for mechanical ventilation were collected. Etiology was studied by multiplex PCR and low-density microarrays for 19 viruses.

RESULTS

A total of 385 patients were positive, 44.94% under 12 months. The most frequently detected viruses were RSV-B: 139, rhinovirus: 114, RSV-A: 111, influenza A H1N1-2009: 93 and bocavirus: 77. Coinfection was detected in 61.81%, 36.36% with 2 viruses, 16.10% and 9.35% with 3 to 4 or more. Coinfection was higher in 2009 with 69.79 vs. 53.88% in 2010. Rhinovirus/RSV-B on 10 times and RSV-A/RSV-B on 5 times were the most detected coinfections. Hospitalization decreased with greater number of viruses (P<0,001). Oxygen therapy was required by 26.75% (one virus was detected in 55.34% of cases). A larger number of viruses resulted in less need for oxygen (P<0,001). Ten cases required mechanical ventilation, 4 patients with bacterial coinfection and 5 with viral coinfection (P=0,69).

CONCLUSIONS

An inverse relationship was found between the number of viruses detected in nasopharyngeal aspirate, the need for oxygen therapy and hospitalization days. More epidemiological studies and improved quantitative detection techniques are needed to define the role of viral coinfections in respiratory disease and its correlation with the clinical severity.

The burden of single virus and viral coinfections on severe lower respiratory tract infections among preterm infants: a prospective birth cohort study in Brazil

BACKGROUND

Respiratory syncytial virus (RSV) is associated with severe lower respiratory tract infection (LRTI), especially in preterm infants. Other viruses, co-detected with RSV, may play a role in the severity of respiratory outcomes.

METHODS

This prospective epidemiologic study of severe LRTI incidence among children born ≤35 weeks gestational age at 3 sites in Brazil (2008-2010) followed a birth cohort for 1 year post-enrollment. Nasal washes from subjects with LRTI were tested for respiratory viruses using polymerase chain reaction. The primary outcome was the incidence of severe LRTI requiring hospitalization associated with RSV infection. Secondary outcomes included identification of viruses associated with LRTI, alone or coinfections, and risk factors associated with severe LRTI.

RESULTS

Among 303 subjects, 176 (58.1%) experienced LRTI. Among these subjects, 162 had samples tested using polymerase chain reaction; 27.8% (45/162) experienced severe LRTI. More subjects with severe LRTI were infected with RSV (30/45, 66.7%) than with other viruses. RSV was present in 33.1% (143/432) of LRTI events tested, 57.3% (82/143) were coinfections. RSV was the virus most frequently associated with severe LRTIs (34/56 events, 60.7%); 50% (17/34 events) single and 50% coinfections. Significantly longer hospital stays were associated with LRTI events involving RSV coinfections compared with RSV single infections (P = 0.012). Infants with severe LRTIs had significantly lower mean RSV-IgG levels at study entry compared with those with nonsevere or no LRTIs (P < 0.05).

CONCLUSIONS

This study confirms the association of RSV alone or as a coinfection with severe LRTI and reinforces the importance of providing adequate prophylaxis for susceptible infants.

Viral coinfection in childhood respiratory tract infections

Introduction

The introduction of molecular techniques has enabled better understanding of the etiology of respiratory tract infections in children. The objective of the study was to analyze viral coinfection and its relationship to clinical severity.

Methods

Hospitalized pediatric patients with a clinical diagnosis of respiratory infection were studied during the period between 2009 and 2010. Clinical and epidemiological data, duration of hospitalization, need for oxygen therapy, bacterial coinfection and need for mechanical ventilation were collected. Etiology was studied by multiplex PCR and low-density microarrays for 19 viruses.

Results

A total of 385 patients were positive, 44.94% under 12 months. The most frequently detected viruses were RSV-B: 139, rhinovirus: 114, RSV-A: 111, influenza A H1N1-2009: 93 and bocavirus: 77. Coinfection was detected in 61.81%, 36.36% with two viruses, 16.10% and 9.35% with three to four or more. Coinfection was higher in 2009 with 69.79 vs 53.88% in 2010. Rhinovirus/RSV-B on 10 times and RSV-A/RSV-B on five times were the most detected coinfections. Hospitalization decreased with greater number of viruses (P<.001). Oxygen therapy was required by 26.75% (one virus was detected in 55.34% of cases). A larger number of viruses resulted in less need for oxygen (P<.001). Ten cases required mechanical ventilation, four patients with bacterial coinfection and five with viral coinfection (P=.69).

Conclusions

An inverse relationship was found between the number of viruses detected in nasopharyngeal aspirate, the need for oxygen therapy and hospitalization days. More epidemiological studies and improved quantitative detection techniques are needed to define the role of viral coinfections in respiratory disease and its correlation with the clinical severity.

Viral etiology of respiratory infections in children in southwestern Saudi Arabia using multiplex reverse-transcriptase polymerase chain reaction

OBJECTIVES

To investigate 15 respiratory viruses in children with acute respiratory tract infections (ARTIs) using multiplex reverse-transcriptase polymerase chain reaction (RT-PCR), and to analyze the clinical and epidemiological features of these viruses.

METHODS

In a cross-sectional study, 135 children, ≤5 years of age who presented with ARTIs in Najran Maternity and Children Hospital, Najran, Saudi Arabia between October 2012 and July 2013 were included. The clinical and sociodemographic data, and the laboratory results were recorded using a standardized questionnaire. Two nasopharyngeal swabs were collected from each child: one for bacteriological examination, and the second for viral detection using multiplex RT-PCR.

RESULTS

A single viral pathogen was detected in 76 patients, viral coinfections in 9, and mixed viral and bacterial pathogens in 15. Respiratory syncytial virus was isolated in 33 patients, human rhinovirus (hRV) in 22, adenovirus (AdV) in 19, human metapneumovirus in 13, influenza virus in 10, parainfluenza virus in 7, human corona virus (hCoV) in 4, and human bocavirus in one.

CONCLUSION

Respiratory syncytial virus, hRV, and AdV were the most frequent viruses, accounting for more than two-thirds of the cases. Other viruses, such as MPV, hCoV NL63, and hCoV OC43, may play a role in pediatric ARTIs. Of significance is the potential use of multiplex RT-PCR to provide epidemiological and virological data for early detection of the emergence of novel respiratory viruses in the era of the Middle East respiratory syndrome coronavirus. 

Viruses associated with influenza-like-illnesses in Papua New Guinea, 2010

Influenza‐like‐illness can be caused by a wide range of respiratory viruses. The etiology of influenza‐like‐illness in developing countries such as Papua New Guinea is poorly understood. The etiological agents associated with influenza‐like‐illness were investigated retrospectively for 300 nasopharyngeal swabs received by the Papua New Guinea National Influenza Centre in 2010. Real‐time PCR/RT‐PCR methods were used for the detection of 13 respiratory viruses. Patients with influenza‐like‐illness were identified according to the World Health Organization case definition: sudden onset of fever (>38°C), with cough and/or sore throat, in the absence of other diagnoses. At least one viral respiratory pathogen was detected in 66.3% of the samples tested. Rhinoviruses (17.0%), influenza A (16.7%), and influenza B (12.7%) were the pathogens detected most frequently. Children <5 years of age presented with a significantly higher rate of at least one viral pathogen and a significantly higher rate of co‐infections with multiple viruses, when compared to all other patients >5 years of age. Influenza B, adenovirus, and respiratory syncytial virus were all detected at significantly higher rates in children <5 years of age. This study confirmed that multiple respiratory viruses are circulating and contributing to the presentation of influenza‐like‐illness in Papua New Guinea. J. Med. Virol. 86:899–904, 2014. © 2013 Wiley Periodicals, Inc.

Severe lower respiratory tract infection in infants and toddlers from a non-affluent population: viral etiology and co-detection as risk factors

BACKGROUND

Lower respiratory tract infection (LRTI) is a major cause of pediatric morbidity and mortality, especially among non-affluent communities. In this study we determine the impact of respiratory viruses and how viral co-detections/infections can affect clinical LRTI severity in children in a hospital setting.

METHODS

Patients younger than 3 years of age admitted to a tertiary hospital in Brazil during the months of high prevalence of respiratory viruses had samples collected from nasopharyngeal aspiration. These samples were tested for 13 different respiratory viruses through real-time PCR (rt-PCR). Patients were followed during hospitalization, and clinical data and population characteristics were collected during that period and at discharge to evaluate severity markers, especially length of hospital stay and oxygen use. Univariate regression analyses identified potential risk factors and multivariate logistic regressions were used to determine the impact of specific viral detections as well as viral co-detections in relation to clinical outcomes.

RESULTS

We analyzed 260 episodes of LRTI with a viral detection rate of 85% (n = 222). Co-detection was observed in 65% of all virus-positive episodes. The most prevalent virus was Respiratory Syncytial Virus (RSV) (54%), followed by Human Metapneumovirus (hMPV) (32%) and Human Rhinovirus (HRV) (21%). In the multivariate models, infants with co-detection of HRV + RSV stayed 4.5 extra days (p = 0.004), when compared to infants without the co-detection. The same trends were observed for the outcome of days of supplemental oxygen use.

CONCLUSIONS

Although RSV remains as the main cause of LRTI in infants our study indicates an increase in the length of hospital stay and oxygen use in infants with HRV detected by RT-PCR compared to those without HRV. Moreover, one can speculate that when HRV is detected simultaneously with RSV there is an additive effect that may be reflected in more severe clinical outcome. Also, our study identified a significant number of children infected by recently identified viruses, such as hMPV and Human Bocavirus (HBov), and this is a novel finding for poor communities from developing countries.

Diagnostic value of respiratory virus detection in symptomatic children using real-time PCR

Background

Acute respiratory tract infections are an important public health problem. Sensitive and rapid diagnostic techniques have been developed and are used in daily clinical practice. Here we evaluate the clinical relevance of detecting 20 common respiratory pathogens by molecular methods in a general pediatric clinic.

Methods

Nasopharynx samples of children < 18 years of age with respiratory symptoms referred to a general pediatric clinic were tested for the presence of 19 viruses and Mycoplasma pneumoniae, using real-time polymerase chain reaction.

Results

Of 177 patients included in this retrospective study, 73% were positive for at least one virus. Respiratory syncytial virus (36.6%) and human rhinovirus (24%) were most frequently detected. Patients in whom a respiratory virus or Mycoplasma pneumoniae was detected, were younger (6 versus 24 months; p < 0.001) and more often hospitalized (116 versus 34; p = 0.001) than patients in whom no respiratory pathogen was detected. Also they were more likely to present with feeding problems, dyspnea, rhinorrhea and wheezing (all p < 0.05) than patients without a respiratory pathogen.

In the majority of cases, clinicians did not change their antibiotic management after detecting a viral respiratory pathogen. No difference in mean Ct value was found between patients with one respiratory pathogen and those with >1 respiratory pathogen (30.5 versus 31.2; p = 0.573).

Conclusion

Routine testing of common respiratory pathogens could lead to a better understanding of their role in disease in children with respiratory symptoms.

Prevalence and Characteristics of Human Metapneumovirus Infection Among Hospitalized Children at High Risk for Severe Lower Respiratory Tract Infection

BACKGROUND

Human metapneumovirus (HMPV) is a significant cause of respiratory tract infections. Little is known about HMPV in children who are at high risk for lower respiratory tract infection (LRTI).

METHODS

To determine the prevalence of HMPV in high-risk children and to identify HMPV risk factors, children ≤24 months with prematurity, chronic lung disease, and/or congenital cardiac disease who were hospitalized with LRTI were prospectively enrolled. Nasopharyngeal aspirates were tested for HMPV, respiratory syncytial virus (RSV), influenza A and B, and parainfluenza types 1-3. Demographics, medical history, and outcomes for those with HMPV and RSV were compared. A multivariate analysis was performed to determine HMPV risk factors.

RESULTS

Over 4 years, 1126 eligible children were enrolled. Pathogens were identified in 61% of subjects. HMPV was identified in 9.0%, second to RSV (45%). Coinfection with HMPV and RSV occurred in <1% of subjects. Subjects infected with HMPV were older (8.2 vs 4.0 months, P < .001), were born more prematurely (27 vs 33 weeks, P < .001), and more commonly had chronic lung disease (59.3% vs 21.8%, P < .001) compared with subjects infected with RSV. In a multivariate analysis that compared children infected with HMPV to all others, increasing age and household exposure to children ages 6-12 were associated with an increased risk, whereas birth at older gestational age and exposure to children age >12 were associated with a decreased risk.

CONCLUSIONS

HMPV was detected in 9% of high-risk children who were hospitalized with lower respiratory tract disease, representing the second most common virus in this population. Compared with all other subjects (including RSV-infected), subjects infected with HMPV were older but were born more prematurely.