Viral epidemiology and severity of respiratory infections in infants in 2009: a prospective study

Severe viral lower respiratory tract infections in Brazilian children: Clinical features of a national cohort

BACKGROUND

The accurate etiological diagnosis of lower respiratory tract infections (LRTI) is essential for their effective clinical management. The extensive use of molecular methods during the COVID-19 pandemic has enabled massive data acquisition on viral lower respiratory tract infections. The current study aims to identify clinical features associated with eight viral agents among children presenting severe LRTI.

METHODS

retrospective cohort study of data from the Brazilian Influenza Epidemiological Surveillance Information System. Patients under 20 years-old who had severe LRTI with etiological confirmation through RT-PCR between 2020 and 2022 were included. Binary logistic regressions were used to examine associations between pathogens and symptoms.

RESULTS

60,657 cases were assessed. The main viral agents detected were Sars-CoV-2 (COV2) (41.2%), Respiratory Syncytial Virus (29.1%), Human Rhinovirus (HRV) (12.1%), and Influenza (FLU) (5.5%). A general mortality rate of 4.3% was observed. The multivariate analysis evidenced that COV2 less likely presented with cough (OR: 0.34; 95%CI: 0.32-0.36), respiratory discomfort (Adjusted Odds Ratio (aOR): 0.61; 95%Confidence Interval (CI): 0.59-0.64), and desaturation (aOR: 0.71; 95%CI: 0.69-0.75). RSV strongly associated with cough (aOR: 2.59; 95%CI: 2.45-2.75) and respiratory discomfort (aOR: 1.54; 95%CI: 1.46-1.62), whereas FLU was linked to fever (aOR: 2.27; 95%CI: 2.06-2.50) and sore throat (aOR: 1.48; 95%CI: 1.34-1.64).

CONCLUSIONS

The viral agents responsible for severe LRTI have distinct associations with clinical features in children.

Characteristics of respiratory viruses' circulation through a six-year period (2016-2022) in a pediatric population in Normandy, France, and the impact of COVID-19 pandemic

IMPORTANCE

The report highlights an epidemiological change in the circulation of respiratory viruses in pediatric populations due to strategies adopted against COVID-19 pandemic. COVID-19 has resulted in a significant increase in requests for multiplex respiratory research to identify the virus responsible for the symptoms. The diagnostic needs have increased, and the number of samples analyzed in 2021-2022 is equal to the samples analyzed over the four epidemic periods preceding the pandemic. The report suggests the importance of active surveillance of respiratory viruses' circulation and new recommendations for respiratory virus detection in pediatric patients.

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.

Coronavirus Infections in the Nervous System of Children: A Scoping Review Making the Case for Long-Term Neurodevelopmental Surveillance

BACKGROUND

The objective of this study was to describe the case literature of human coronavirus infections in the nervous system of children, including from SARS-CoV-2, and to provide guidance to pediatric providers for managing the potential long-term effects on neurodevelopment of human coronavirus infections in the nervous system.

METHODS

Using a structured strategy, the PubMed and Ovid:Embase databases were queried for articles about the clinical presentation and pathophysiology of coronavirus infections in the nervous system of children and young adults, aged 0 to 24 years.

RESULTS

Of 2302 articles reviewed, 31 described SARS-CoV-2 infections in the nervous system of children and 21 described other human coronaviruses: HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, MERS-CoV, SARS-CoV-1. Excepting MERS-CoV, we found cases of neurological disease in children from each human coronavirus. Children with non-SARS-CoV-2 infections have suffered acute flaccid paralysis, acute disseminated encephalomyelitis, encephalitis, and seizures. In addition, cases of ischemic, hemorrhagic, and microvascular strokes have occurred in children with SARS-CoV-2. Patients with multisystem inflammatory syndrome in children have suffered encephalitis, stroke, pseudotumor cerebri syndrome, and cytotoxic lesions of deep brain structures. Despite these reports, few articles evaluated the impact of human coronavirus infections on long-term neurodevelopmental domains including cognitive, language, academic, motor, and psychosocial outcomes.

CONCLUSIONS

Neurological manifestations of human coronavirus infections can cause severe disease in children. The case literature suggests a critical gap in knowledge of the long-term effects on child neurodevelopment of these infections. As the current SARS-CoV-2 pandemic continues, this gap must be filled to facilitate optimal outcomes in recovering children.

Epidemiology and seasonality of acute respiratory infections in hospitalized children over four consecutive years (2012-2016)

•

The respiratory viral profile varied with age.

•

The distribution of viruses is variable over the year depending on the species.

•

Persistence of non-enveloped viruses throughout the year.

•

Atmospheric temperature was rarely a limiting factor in the circulation of viruses.

Background

Acute respiratory infections are a principal cause of illness and mortality especially in young children worldwide.

Objectives

To study the epidemiology and seasonality of viral respiratory infections in hospitalized children (under the age of 16) between September 2012 and August 2016.

Study design

Nasopharyngeal swabs or aspirates were collected from 3199 symptomatic patients and then screened with a routine multiplex PCR assay.

Results

Respiratory viruses were detected for 1624 (50.8%) of the 3199 children in the study population. Of these, 210 (13.3%) were positive for two viruses, 28 (1.7%) were positive for three, and 3 (0.2%) were positive for four. The viral profile varied with age. Some viruses were significantly more frequent in children under the age of 1 month (such as human respiratory syncytial virus (p < 0.0001)), whereas others were significantly more frequent in children over that age (such as influenza viruses (p < 0.0001) and adenoviruses (p = .0006)). The distribution of viruses is variable over the year depending on the species. However, the atmospheric temperature was rarely found to be a limiting factor in the circulation of respiratory viruses.

Conclusions

our results constitute a detailed description of the distribution of respiratory viruses among hospitalized children over four consecutive years. Our data notably highlight the persistence of non-enveloped viruses and some enveloped viruses throughout the year–regardless of temperature variations.

SOFIA®RSV: prospective laboratory evaluation and implementation of a rapid diagnostic test in a pediatric emergency ward

Background

Respiratory syncytial virus (RSV) is responsible for severe respiratory infections and higher costs in medical care. The two aims of this work were to assess the performances of SOFIA^®RSV tests in “real-life-laboratory” conditions (study 1) and implemented at point-of-care testing in a pediatric emergency department (ED, study 2), during two consecutive winter seasons.

Methods

In study 1, fresh nasopharyngeal swabs from patients of all ages were sampled in 1.5 ml of Universal virological Transport Medium (UTM) and prospectively tested using SOFIA^®RSV tests. In study 2, conducted in a pediatric ED, nasopharyngeal swabs were placed in 3 ml of UTM. All SOFIA^®RSV tests were confirmed by molecular testing, considered as reference method. The epidemiological and clinical features of tested patients, as well as the care of these patients after obtaining quick results were evaluated.

Results

The sensitivities of SOFIA^®RSV in infants (aged under 24 months) performed in the laboratory and in the pediatric ED were respectively 95% (95% CI: 86.8–98.1) and 74.8% (95% CI: 68.0–80.9) compared to PCR. In study 1, the sensitivity among children (from 2 to 15 years old) and adults (above 15 years old) dropped to 45% (95% CI: 23.1–68.5) and 59% (95% CI: 32.9–81.6), respectively. In study 2, there were some differences in bed-management of SOFIA^®RSV positive compared to SOFIA^®RSV negative infants.

Conclusions

SOFIA^®RSV tests performed in the laboratory and in the pediatric ED show high and satisfactory sensitivities among young children under 24 months, which supports its robustness and reliability. However, the impact of these tests on patient care at point-of-care cannot be clearly assessed when considering the limits of the study 2 design.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2557-8) contains supplementary material, which is available to authorized users.

Interference Between Respiratory Syncytial Virus and Human Rhinovirus Infection in Infancy

BACKGROUND

Respiratory syncytial virus (RSV) and human rhinovirus (HRV) are the most common viruses associated with acute respiratory tract infections in infancy. Viral interference is important in understanding respiratory viral circulation and the impact of vaccines.

METHODS

To study viral interference, we evaluated cases of RSV and HRV codetection by polymerase chain reaction in 2 prospective birth cohort studies (the Infant Susceptibility to Pulmonary Infections and Asthma Following RSV Exposure [INSPIRE] study and the Tennessee Children's Respiratory Initiative [TCRI]) and a double-blinded, randomized, controlled trial (MAKI), using adjusted multivariable regression analyses.

RESULTS

Among 3263 respiratory tract samples, 24.5% (798) and 37.3% (1216) were RSV and HRV positive, respectively. The odds of HRV infection were significantly lower in RSV-infected infants in all cohorts, with adjusted odds ratios of 0.30 (95% confidence interval [CI], .22-.40 in the INSPIRE study, 0.18 (95% CI, .11-.28) in the TCRI (adjusted for disease severity), and 0.34 (95% CI, .16-.72) in the MAKI trial. HRV infection was significantly more common among infants administered RSV immunoprophylaxis, compared with infants who did not receive immunoprophylaxis (OR, 1.65; 95% CI, 1.65-2.39).

CONCLUSIONS

A negative association of RSV on HRV codetection was consistently observed across populations, seasons, disease severity, and geographical regions. Suppressing RSV infection by RSV immunoprophylaxis might increase the risk of having HRV infection.

[The interactions between microorganisms and the small airways. A paediatric focus]

The spectrum of respiratory viruses is expanding and emerging diseases have been described regularly over the last fifteen years. The origin of these emerging respiratory viruses may be zoonotic (by crossing species barrier, after changes to RNA viruses such as avian influenza virus type A or coronaviruses), or related to the use of new identification techniques (metapneumovirus, bocavirus). The relationship between bronchiolitis and asthma is now better understood thanks to prospective follow up of birth cohorts. The role of rhinovirus has become predominant with respect to respiratory syncytial virus. The identification of predisposing factors immunological, functional, atopic and genetic, for the onset of asthma after rhinovirus infection suggests that viral infection reveals a predisposition rather than itself being a cause of asthma. The role of bacteria in the natural history of asthma is also beginning to be better understood. The results of the COPSAC Danish cohort have shown the frequency of bacterial identification during wheezy episodes before 3 years, and the impact of bacterial colonization at the age of one month on the onset of asthma by age 5 years. The role of bacterial infections in severe asthma in young children is also discussed.

Usefulness of multiplex PCR methods and respiratory viruses' distribution in children below 15 years old according to age, seasons and clinical units in France: A 3 years retrospective study

Background

To date, only influenza and RSV testing are recommended for respiratory viruses’ detection in paediatric units. In this study, we described, according to seasons, ages and clinical units, the results obtained in children (<15 years old) by multiplex-PCR (mPCR) tests allowing a quick and wide range detection of all respiratory viruses. These results were also compared with RSV specific detection.

Methods

All nasopharyngeal mPCR and RSV tests requested by clinicians in our French teaching hospitals group between 2011 and 2014 were retrospectively included. All repeated samples for the same children in the same month were discarded.

Results

Of the 381 mPCR tests (344 children) performed, 51.4% were positive. Positivity and viral co-infection rates were higher in the 6–36 months old strata (81% and 25%, p<0.0001 and p = 0.04, respectively). Viral distribution showed strong variations across ages. During specific influenza epidemic periods, only 1/39 (2.5%) mPCR tests were positive for influenza and 19/39 (48.7%) for other viruses. During specific RSV epidemic periods, only 8/46 (17.4%) mPCR tests were positive for RSV and 14/46 (30.4%) for other viruses. 477/1529 (31.2%) of RSV immunochromatography-tests were positive. Among the negatives immunochromatography-test also explored by mPCR, 28/62 (31%) were positive for other respiratory viruses.

Conclusion

This study provides a wide description of respiratory viruses’ distribution among children in hospital settings using mPCR over 3 years. It emphasizes the number of undiagnosed respiratory viruses according to the current diagnosis practice in France and gives a better picture of respiratory viruses identified in hospital settings by mPCR all over the year in France.

Prevalence and Seasonal Distribution of Respiratory Viruses During the 2014 - 2015 Season in Istanbul

Background

Acute respiratory tract infection (ARTI) is one of the most common infections worldwide, causing significant morbidity and mortality.

Objectives

This study was conducted to determine the prevalence and seasonal distribution of respiratory viruses in our region, in children and adults with a pre-diagnosis of ARTI.

Methods

A total of 845 nasopharyngeal swab specimens were analyzed with the RespiFinder Smart 22 kit (PathoFinder BV, Netherlands) and the Rotor-Gene 6000 real-time PCR system.

Results

At least one pathogen was detected in 612 (72.4%) of the specimens. Overall, 902 pathogens were detected; 821 (91%) were viruses and 81 (9%) were bacteria. The most commonly detected pathogens were influenza A virus (IFV-A) (n = 219), influenza B virus (IFV-B) (n=157), rhinovirus/enterovirus (n = 107), human bocavirus (HBoV) (n = 91), respiratory syncytial virus (RSV) A/B (n = 64), adenovirus (n = 56), human coronaviruses (n = 51), Mycoplasma pneumoniae (n = 49), parainfluenza viruses (n = 40), human metapneumovirus (n = 36), Bordetella pertussis (n = 15), Legionella pneumophila (n = 11), and Chlamydophila pneumoniae (n = 6), respectively. Among the 215 (25.4%) co-infected cases, IFV-A/HBoV and IFV-A/IFV-B were the most common co-infections. IFV-A was the most prevalent agent in all age groups except for children under 5 years of age, in whom RSV A/B was the most common pathogen. Approximately two thirds of the respiratory viruses were detected in early spring and winter, with peaks in January, March, and April.

Conclusions

With regard to the prevalence and seasonal distribution of respiratory viruses, our epidemiological data for the 2014 - 2015 season in Istanbul showed a predominance of IFV-A infections with a peak activity in early spring. Enhanced surveillance and early detection of respiratory viral pathogens can be useful in the diagnosis, treatment, and prevention of ARTIs, and for guiding the development of appropriate public health strategies.

Study and interest of cellular load in respiratory samples for the optimization of molecular virological diagnosis in clinical practice

BACKGROUND

Respiratory viral diagnosis of upper respiratory tract infections has largely developed through multiplex molecular techniques. Although the sensitivity of different types of upper respiratory tract samples seems to be correlated to the number of sampled cells, this link remains largely unexplored.

METHODS

Our study included 800 upper respiratory tract specimens of which 400 negative and 400 positive for viral detection in multiplex PCR. All samples were selected and matched for age in these 2 groups. For the positive group, samples were selected for the detected viral species.

RESULTS

Among the factors influencing the cellularity were the type of sample (p < 0.0001); patient age (p < 0.001); viral positive or negative nature of the sample (p = 0.002); and, for the positive samples, the number of viral targets detected (0.004 < p < 0.049) and viral species.

CONCLUSION

The cellular load of upper respiratory samples is multifactorial and occurs for many in the sensitivity of molecular detection. However it was not possible to determine a minimum cellularity threshold allowing molecular viral detection. The differences according to the type of virus remain to be studied on a larger scale.

Probiotics for prevention and treatment of respiratory tract infections in children: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Respiratory tract infections (RTIs) represent one of the main health problems in children. Probiotics are viable bacteria that colonize the intestine and affect the host intestinal microbial balance. Accumulating evidence suggests that probiotic consumption may decrease the incidence of or modify RTIs. The authors systematically reviewed data from randomized controlled trials (RCTs) to investigate the effect of probiotic consumption on RTIs in children.

METHODS

MEDLINE/PubMed, Embase, Cochrane Library, and Web of Science were systematically searched for RCTs regarding the effect of probiotics on RTIs in children. The outcomes included number of children experienced with at least 1 RTI episode, duration of illness episodes, days of illness per subject, and school/day care absenteeism due to infection. A random-effects model was used to calculate pooled relative risks, or mean difference (MD) with the corresponding 95% confidence interval (CI).

RESULTS

A total of 23 trials involving 6269 children were eligible for inclusion in the systematic review. None of the trials showed a high risk of bias. The quality of the evidence of outcomes was moderate. The age range of subjects was from newborn to 18 years. The results of meta-analysis showed that probiotic consumption significantly decreased the number of subjects having at least 1 RTI episode (17 RCTs, 4513 children, relative risk 0.89, 95% CI 0.82-0.96, P = 0.004). Children supplemented with probiotics had fewer numbers of days of RTIs per person compared with children who had taken a placebo (6 RCTs, 2067 children, MD -0.16, 95% CI -0.29 to 0.02, P = 0.03), and had fewer numbers of days absent from day care/school (8 RCTs, 1499 children, MD -0.94, 95% CI -1.72 to -0.15, P = 0.02). However, there was no statistically significant difference of illness episode duration between probiotic intervention group and placebo group (9 RCTs, 2817 children, MD -0.60, 95% CI -1.49 to 0.30, P = 0.19).

CONCLUSION

Based on the available data and taking into account the safety profile of RCTs, probiotic consumption appears to be a feasible way to decrease the incidence of RTIs in children.

Probiotics for the treatment of upper and lower respiratory-tract infections in children: systematic review based on randomized clinical trials

OBJECTIVES

Evaluate the effect of probiotics on the symptoms, duration of disease, and the occurrence of new episodes of upper and lower respiratory infections in healthy children.

SOURCES

In order to identify eligible randomized controlled trials, two reviewers accessed four electronic databases [MEDLINE/PubMed, Scopus (Elsevier), Web of Science, and Cochrane (Cochrane VHL)], as well as ClinicalTrials.gov until January 2015. Descriptors were determined by using the Medical Subject Headings tool, following the same search protocol.

SUMMARY OF THE FINDINGS

Studies showed to be heterogeneous regarding strains of probiotics, the mode of administration, the time of use, and outcomes. The present review identified 11 peer-reviewed, randomized clinical trials, which analyzed a total of 2417 children up to 10 incomplete years of age. In the analysis of the studies, reduction in new episodes of disease was a favorable outcome for the use of probiotics in the treatment of respiratory infections in children. It is noteworthy that most of these studies were conducted in developed countries, with basic sanitation, health care, and strict, well-established and well-organized guidelines on the use of probiotics. Adverse effects were rarely reported, demonstrating probiotics to be safe.

CONCLUSIONS

Despite the encouraging results - reducing new episodes of respiratory infections - the authors emphasize the need for further research, especially in developing countries, where rates of respiratory infections in children are higher when compared to the high per capita-income countries identified in this review.

Epidemiology and virology of acute respiratory infections during the first year of life: a birth cohort study in Vietnam

BACKGROUND

Understanding viral etiology and age-specific incidence of acute respiratory infections in infants can help identify risk groups and inform vaccine delivery, but community-based data is lacking from tropical settings.

METHODS

One thousand four hundred and seventy-eight infants in urban Ho Chi Minh City and 981 infants in a semi-rural district in southern Vietnam were enrolled at birth and followed to 1 year of age. Acute respiratory infection (ARI) episodes were identified through clinic-based illness surveillance, hospital admissions and self-reports. Nasopharyngeal swabs were collected from infants with respiratory symptoms and tested for 14 respiratory pathogens using multiplex reverse transcription-polymerase chain reaction.

RESULTS

Estimated incidence of ARI was 542 and 2691 per 1000 infant-years, and hospitalization rates for ARI were 81 and 138 per 1000 infant-years, in urban and semi-rural cohorts, respectively, from clinic- and hospital-based surveillance. However self-reported ARI episodes were just 1.5-fold higher in the semi-rural versus urban cohort, indicating that part of the urban-rural difference was explained by under-ascertainment in the urban cohort. Incidence was higher in infants ≥6 months of age than <6 months, but this was pathogen-specific. One or more viruses were detected in 53% (urban) and 64% (semi-rural) of samples from outpatients with ARI and in 78% and 66% of samples from hospitalized ARI patients, respectively. The most frequently detected viruses were rhinovirus, respiratory syncytial virus, influenza virus A and bocavirus. ARI-associated hospitalizations were associated with longer stays and more frequent ICU admission than other infections.

CONCLUSIONS

ARI is a significant cause of morbidity in Vietnamese infants and influenza virus A is an under-appreciated cause of vaccine-preventable disease and hospitalizations in this tropical setting. Public health strategies to reduce infant ARI incidence and hospitalization rates are needed.

[Winter viral ecology in a pediatric intensive care unit: a prospective study]

Le but de cette étude prospective était d’évaluer l’épidémiologie des virus respiratoires chez les enfants hospitalisés dans une unité de réanimation et de soins continus pédiatriques pendant 3 mois d’hiver, en 2012–2013. Ont été inclus tous les enfants admis en réanimation pédiatrique du centre hospitalier universitaire (CHU) de Caen et ayant bénéficié d’une recherche d’infection par un virus respiratoire à partir d’un prélèvement nasal analysé par amplification génique (PCR) multiplex. Sur 105 enfants admis, 84 répondaient aux critères d’inclusion. Trente-sept enfants présentaient un ou plusieurs symptômes respiratoires à l’admission. Cinquante-quatre échantillons étaient positifs (64,3 %) avec 70 virus détectés. Le virus dont la prévalence était la plus élevée était le virus respiratoire syncytial (VRS) (n = 28 ; 40,0 %), suivi par le rhinovirus (n = 24 ; 34,3 %). Parmi les enfants sans symptômes respiratoires, 42,6 % étaient infectés par un ou plusieurs virus. Aucune différence de durée d’hospitalisation, de durée de ventilation mécanique n’a été mise en évidence en fonction du virus détecté. La principale limite de cette étude est l’analyse par PCR, beaucoup plus sensible que d’autres méthodes de détection, notamment chez des sujets asymptomatiques sur le plan respiratoire. Cette étude révèle cependant un taux élevé d’infections respiratoires causées par des virus chez les enfants qui ne présentent pas de symptômes respiratoires à leur admission en unité de réanimation et soins continus. Elle suggère un intérêt du dépistage de ces infections virales à l’admission des enfants et un bénéfice à l’extension des mesures d’isolement pour tous les enfants en réanimation pédiatrique.

Clinical evaluation of viral acute respiratory tract infections in children presenting to the emergency department of a tertiary referral hospital in the Netherlands

Background

The relative incidence and clinical impact of individual respiratory viruses remains unclear among children presenting to the hospital emergency department with acute respiratory tract infection (ARTI).

Methods

During two winter periods, respiratory virus real-time multiplex PCR results were evaluated from children (< 18 years) presenting to the emergency department of a tertiary referral hospital with ARTI that had been sampled within 48 hours of hospital presentation. In an attempt to identify virus-specific distinguishing clinical features, single virus infections were correlated with presenting signs and symptoms, clinical findings and outcomes using multivariate logistic regression.

Results

In total, 274 children with ARTI were evaluated and most were aged < 3 years (236/274, 86%). PCR detected respiratory viruses in 224/274 (81.8%) children and included 162 (59%) single and 62 (23%) mixed virus infections. Respiratory syncytial virus (RSV) and human rhinovirus (HRV) single virus infections were common among children aged < 3 years, but proportional differences compared to older children were only significant for RSV (95% CI 1.3–15). Clinical differentiation between viral ARTIs was not possible due to common shared presenting signs and symptoms and the high frequency of mixed viral infections. We observed virus-associated outcome differences among children aged < 3 years. Oxygen treatment was associated with RSV (OR 3.6) and inversely correlated with FLU (OR 0.05). Treatment with steroids (OR 3.4) or bronchodilators (OR 3.4) was associated with HRV. Severe respiratory complications were associated with HRV (OR 3.5) and inversely correlated with RSV (OR 0.24).

Conclusions

Respiratory viruses are frequently detected in young children presenting to the hospital emergency department with ARTI and require PCR diagnosis since presenting signs and symptoms are not discriminant for a type of virus. RSV and HRV bear a high burden of morbidity in the pediatric clinical setting.

Probiotics for the prevention of pediatric upper respiratory tract infections: a systematic review

BACKGROUND

Acute upper respiratory tract infections (URTIs) contribute substantially to pediatric morbidity and mortality worldwide. Prevention of these infections in childhood is a very important public health challenge. Previous systematic reviews, including both adult and childhood populations, have reported that probiotics seem promising, but with modest evidence. This study aimed to focus on prophylactic probiotic use in the prevention of URTIs in childhood.

METHODS

Relevant trials on two databases were identified in a systematic review, from inception to June 2014. Study selection, data extraction and quality assessment were carried out by two reviewers. In this review, the effects of probiotics, particularly the Lactobacillus and Bifidobacterium strains, on the incidence and symptom scores of URTI in otherwise healthy children were evaluated for the first time. This review comprises 14 randomized controlled trials (RCTs) applied to a pediatric population with high-quality methodology.

RESULTS

This systematic review suggests that probiotics in immunocompetent children have a modest effect both in diminishing the incidence of URTIs and the severity of the infection symptoms.

CONCLUSIONS

At least one beneficial effect of prophylactic probiotic was observed in the majority of RCTs. Even a minimal reduction of 5 - 10% in the incidence of URTIs would have an important clinical and economic mpact on societies. Furthermore, the long-term administration of probiotics appeared to have a good safety profile in childhood and none of the studies reported any serious adverse events related to the probiotic strain.

Viral etiology of respiratory tract infections in children at the pediatric hospital in Ouagadougou (Burkina Faso)

Background

Acute respiratory infections (ARIs) are a major cause of morbidity and mortality in children in Africa. The circulation of viruses classically implicated in ARIs is poorly known in Burkina Faso. The aim of this study was to identify the respiratory viruses present in children admitted to or consulting at the pediatric hospital in Ouagadougou.

Methods

From July 2010 to July 2011, we tested nasal aspirates of 209 children with upper or lower respiratory infection for main respiratory viruses (respiratory syncytial virus (RSV), metapneumovirus, adenovirus, parainfluenza viruses 1, 2 and 3, influenza A, B and C, rhinovirus/enterovirus), by immunofluorescence locally in Ouagadougou, and by PCR in France. Bacteria have also been investigated in 97 samples.

Results

153 children (73.2%) carried at least one virus and 175 viruses were detected. Rhinoviruses/enteroviruses were most frequently detected (rhinovirus n = 88; enterovirus n = 38) and were found to circulate throughout the year. An epidemic of RSV infections (n = 25) was identified in September/October, followed by an epidemic of influenza virus (n = 13), mostly H1N1pdm09. This epidemic occurred during the period of the year in which nighttime temperatures and humidity were at their lowest. Other viruses tested were detected only sporadically. Twenty-two viral co-infections were observed. Bacteria were detected in 29/97 samples with 22 viral/bacterial co-infections.

Conclusions

This study, the first of its type in Burkina Faso, warrants further investigation to confirm the seasonality of RSV infection and to improve local diagnosis of influenza. The long-term objective is to optimize therapeutic management of infected children.

Respiratory syncytial virus-associated hospitalizations in pre-mature infants in Lima, Peru

We conducted a prospective cohort study in four hospitals in Lima, Peru in infants with a birth weight ≤ 1,500 g followed from birth hospital discharge up to 1 year of age to determine the incidence of respiratory syncytial virus (RSV) hospitalizations. We enrolled 222 infants from March of 2009 to March of 2010: 48 infants with a birth weight < 1,000 g and 174 infants with a birth weight of 1,000-1,500 g (birth weight = 1,197 ± 224 g; gestational age = 30.1 ± 2.6 weeks). There were 936 episodes of respiratory infections; the incidence of respiratory infections during the first 1 year of life was 5.7 episodes/child-years. The incidence of RSV respiratory infections that required emergency room management was 103.9 per 1,000 child-years, and the incidence of RSV hospitalizations was 116.2 per 1,000 child-years (244.9 in infants with a birth weight < 1,000 g and 88.9 in infants 1,000-1,500 g; P < 0.05). The incidence of RSV respiratory infections that required emergency management or hospitalization is high among pre-mature infants in Lima.

[Viral epidemiology and clinical severity during the peak of the influenza A(H1N1) variant epidemic in febrile respiratory diseases of children]

En mars 2009, un nouveau virus a fait émergence, le virus Influenzae A(H1N1) variant. Nous avons voulu en étudier la répercussion médicale.

Objectifs

Définir la prévalence virale dans les atteintes respiratoires fébriles hospitalisées de l’enfant en période d’épidémie grippale A(H1N1) variant et déterminer les caractéristiques cliniques, paracliniques et évolutives liées aux virus identifiés.

Méthodes

Il s’est agi d’une étude épidémiologique, prospective, monocentrique menée à l’hôpital des Enfants du centre hospitalier universitaire de Bordeaux (Aquitaine, France) pendant l’épidémie grippale du 23 novembre au 20 décembre 2009 inclus. Tous les enfants hospitalisés pour atteinte respiratoire fébrile ont été inclus.

Résultats

Soixante-treize enfants ont été inclus. Une identification virale a été possible dans 52 % des cas, incluant 23 % de A(H1N1) variant [A(H1N1)v] et 29 % d’autres identifications dont 22 % de virus respiratoires syncitiaux. Une seule co-infection a été observée entre le virus [A(H1N1)v] et un pool viral (adénovirus ou virus para-influenzae ou bocavirus). Il n’existait pas de différence significative concernant l’âge, le sexe ou les facteurs de risque de gravité en fonction des virus identifiés. Concernant le virus [A(H1N1)v], les symptômes les plus fréquents étaient l’altération de l’état général, la toux, les atteintes oto-rhino-laryngologiques et les anomalies de la fréquence respiratoire, avec significativement moins de signes de lutte et d’anomalie auscultatoire mais plus de convulsions. Sur le plan paraclinique, il n’y avait pas de différence significative entre les groupes. Évolution et prise en charge ont été comparables.

Conclusion

Une faible prédominance du virus [A(H1N1)v] a été notée pendant l’épidémie grippale en Aquitaine dans les atteintes respiratoires fébriles justifiant une hospitalisation. Les caractéristiques cliniques, paracliniques et évolutives étaient peu spécifiques. L’ensemble de ces éléments n’a pas révélé de gravité particulière liée au virus [A(H1N1)v].

Lactobacillus rhamnosus GG supplementation for preventing respiratory infections in children: a meta-analysis of randomized, placebo-controlled trials

OBJECTIVE

To systematically review the effectiveness of administering Lactobacillus rhamnosus GG (LGG) for preventing respiratory infections in children.

DESIGN

Systematic Review and Meta-analysis.

DATA SOURCES

Electronic databases and trial registries.

RESULTS

Four RCTs involving 1805 participants met the inclusion criteria. Compared with placebo, LGG administration was associated with a reduced incidence of acute otitis media (four RCTs, n=1805, RR 0.76, 95% CI 0.64-0.91, fixed effects model, NNT 17, 95% CI 11-46), a reduced risk of upper respiratory infections (one RCT, n=281, RR 0.62, 95% CI 0.50-0.78, NNT 4, 95% CI 3-8) and antibiotic treatments (four RCTs, n=1805, RR 0.80, 95% CI 0.71-0.91, fixed effects model). There was no significant difference between the LGG and the control groups in the risk of overall respiratory infections and the incidence of lower respiratory infections. However, subgroup analysis of two studies on children older than 1 year showed significant reduction in the risk of overall respiratory infections (two RCTs, n=794, RR 0.73, 95% CI 0.57-0.92, random effects model, NNT 8, 95% CI 5-14). Adverse effects were similar in both groups. No serious adverse events were reported.

CONCLUSION

The administration of Lactobacillus rhamnosus GG compared with placebo has the potential to reduce the incidence of acute otitis media, the upper respiratory infections and antibiotic use in children.

Respiratory syncytial virus--a comprehensive review

Respiratory syncytial virus (RSV) is amongst the most important pathogenic infections of childhood and is associated with significant morbidity and mortality. Although there have been extensive studies of epidemiology, clinical manifestations, diagnostic techniques, animal models and the immunobiology of infection, there is not yet a convincing and safe vaccine available. The major histopathologic characteristics of RSV infection are acute bronchiolitis, mucosal and submucosal edema, and luminal occlusion by cellular debris of sloughed epithelial cells mixed with macrophages, strands of fibrin, and some mucin. There is a single RSV serotype with two major antigenic subgroups, A and B. Strains of both subtypes often co-circulate, but usually one subtype predominates. In temperate climates, RSV infections reflect a distinct seasonality with onset in late fall or early winter. It is believed that most children will experience at least one RSV infection by the age of 2 years. There are several key animal models of RSV. These include a model in mice and, more importantly, a bovine model; the latter reflects distinct similarity to the human disease. Importantly, the prevalence of asthma is significantly higher amongst children who are hospitalized with RSV in infancy or early childhood. However, there have been only limited investigations of candidate genes that have the potential to explain this increase in susceptibility. An atopic predisposition appears to predispose to subsequent development of asthma and it is likely that subsequent development of asthma is secondary to the pathogenic inflammatory response involving cytokines, chemokines and their cognate receptors. Numerous approaches to the development of RSV vaccines are being evaluated, as are the use of newer antiviral agents to mitigate disease. There is also significant attention being placed on the potential impact of co-infection and defining the natural history of RSV. Clearly, more research is required to define the relationships between RSV bronchiolitis, other viral induced inflammatory responses, and asthma.

Does respiratory virus coinfection increases the clinical severity of acute respiratory infection among children infected with respiratory syncytial virus?

BACKGROUND

Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory infection in children less than 5 years of age. The impact of non-RSV respiratory virus coinfection on the severity of RSV disease is unknown.

METHODS

This hospital-based prospective study was conducted in Nagasaki, Japan, on all children less than 5 years of age with acute respiratory infection (ARI) who had undergone a rapid RSV diagnostic test between April 2009 and March 2010. Thirteen respiratory viruses were identified from nasopharyngeal swab samples using a multiplex polymerase chain reaction; polymerase chain reaction-positive samples were considered as confirmed respiratory virus infections. The cases were classified into 3 categories (pneumonia, moderate-to-severe nonpneumonic ARI and mild ARI) according to the findings of the chest radiograph and the hospitalization records.

RESULTS

Among 384 cases enrolled, 371 were eligible for analysis, of whom 85 (23%) were classified as pneumonia cases; 137 (37%) as moderate-to-severe nonpneumonic ARI cases and 162 (40%) as mild ARI cases. RSV was detected in 172 cases (61.6%), and 31 cases (18.0%) had double or triple infections with other respiratory viruses. RSV infection was more frequently observed in pneumonia cases (odds ratio [OR]: 2.3; 95% confidence interval [CI]: 1.31-3.9) and moderate-to-severe nonpneumonic ARI cases (OR: 2.95; 95% CI: 1.82-4.78) than in mild ARI cases. The association with moderate-to-severe nonpneumonic ARI cases was stronger with RSV/non-RSV respiratory virus coinfection (adjusted OR: 4.91; 95% CI: 1.9-12.7) than with RSV single infection (adjusted OR: 2.77; 95% CI: 1.64-4.7).

CONCLUSIONS

Non-RSV respiratory virus coinfection is not uncommon in RSV-infected children and may increase the severity of RSV disease.