Lower respiratory infections among hospitalized children in New Caledonia: a pilot study for the Pneumonia Etiology Research for Child Health project

Respiratory virus concentrations in human excretions that contribute to wastewater: a systematic review and meta-analysis

Concentrations of nucleic acids from a range of respiratory viruses in wastewater solids collected from wastewater treatment plants correlate to clinical data on disease occurrence in the community contributing to the wastewater. Viral nucleic acids enter wastewater from excretions deposited in toilets or drains. To relate measured concentrations in wastewater at a treatment plant to the number of community infections, viral nucleic-acid concentrations in human excretions are needed as inputs to a mass balance model. Here, we carried out a systematic review and meta-analysis to characterize the concentrations and presence of influenza A and B, respiratory syncytial virus, metapneumovirus, parainfluenza virus, rhinovirus, and seasonal coronaviruses in stool, urine, mucus, sputum, and saliva. We identified 220 data sets from 50 articles and reported viral concentrations and presence in these excretions. Data were unevenly distributed across virus type (with the most available for influenza) and excretion type (with the most available for respiratory excretions). Most articles only reported the presence or absence of the virus in a cross-sectional study design. There is a need for more concentration data, including longitudinal data, across all respiratory virus and excretion types. Such data would allow quantitatively linking virus wastewater concentrations to numbers of infected individuals.

Utility of Induced Sputum in Assessing Bacterial Etiology for Community-Acquired Pneumonia in Hospitalized Children

BACKGROUND

Diagnostic testing for bacterial etiology of community-acquired pneumonia (CAP) is insensitive. Induced sputum (IS) is an attractive option for the evaluation of the lower respiratory tract.

METHODS

Children aged 0-18 years with CAP were enrolled in the Etiology of Pneumonia in the Community (EPIC) study between 2010 and 2012. Blood and respiratory specimens were assessed by culture and polymerase chain reaction (PCR). The radiographic CAP was determined by a study radiologist. Sputum was induced with hypertonic saline. IS specimen was high quality (HQ) if Gram stain showed >25 white blood and <10 epithelial cells per low-powered field; all others were low quality (LQ). We compared IS pathogen prevalence between HQ and LQ IS, and by radiographic pneumonia. Pathogen concordance with EPIC etiology was assessed. Length of stay (LOS) was compared by receipt of IS pathogen-concordant antibiotics.

RESULTS

Out of 977 children, 916 (94%) children enrolled in Memphis, Tennessee, produced IS; 794 (87%) had radiographic CAP and 174 (19%) were HQ. HQ IS yielded pathogenic bacteria more often than LQ (64% vs 44%; P < .01); however, pathogens were isolated at similar rates in HQ IS in patients with and without radiographic CAP (64% vs. 63%; P = .6). Pathogens from study specimens matched an IS pathogen in only 9/42 (21%) patients with radiographic CAP. Median LOS was similar among patients with radiographic CAP regardless of receipt of IS pathogen-concordant antibiotics (3.1 days), non-pathogen-concordant antibiotics (2.7 days), or no antibiotics (3.2 days; P = .5).

CONCLUSIONS

Bacterial pathogens were isolated from most IS cultures regardless of radiographic CAP and quality of IS. IS cultures infrequently corresponded with sterile site cultures. Isolation of pathogens from pediatric IS reflects oropharyngeal carriage and is insufficient to determine bacterial etiology of CAP.

Bacterial etiology of pneumonia in children up to 2 months of age: a systematic review

Background: Following the widespread introduction of childhood pneumococcal conjugate vaccines (PCVs), a significant impact on pneumonia mortality in children under five years of age has been reported. It is still unknown whether PCVs are expected to reduce pneumonia burden in younger children, particularly ≤2 months of age, as current evidence on the role of S. pneumoniae in pneumonia etiology in this age group is scarce. We aimed to summarize the evidence of bacterial etiology of pneumonia in children ≤2 months of age. Methods: We conducted a systematic review considering studies evaluating a variety of syndromes associated with pneumonia, and reporting on laboratory confirmed etiologies, considering any diagnostic method and a variety of clinical specimens.  We searched Medline/PubMed, Embase, WoS, Central and Index Medicus Global published in any language till April 30th, 2021. We included studies addressing the outcomes of interest in children ≤2 months of age and reporting on clinical trials, observational studies, and case series with at least 10 events. Screening of citations and data extraction were conducted in duplicate by independent reviewers, according to the study protocol registered on PROSPERO. Descriptive analyses of the various etiologic agents by syndrome are reported. Results: We identified 3,744 citations, of which 22 publications reporting on 13 studies were included. Study methods varied significantly. Nonetheless, gram positive organisms, in particular S. pneumoniae, were identified as important etiologic agents of pneumonia in children ≤2 months of age. Viral etiologies, in particular Respiratory Syncytial Virus, Rhinovirus, and Influenza were also identified. Conclusions: This review provides the most comprehensive analysis to date of the etiologies of pneumonia in children ≤2 months of age, suggesting that PCV impact is expected to occur in this age group. These results also have major implications for diagnosis and treatment of pneumonia in this age group.

Viral and Atypical Bacterial Detection in Young Nepalese Children Hospitalized with Severe Pneumonia

Respiratory viruses cause a substantial proportion of respiratory tract infections in children but are underrecognized as a cause of severe pneumonia hospitalization in low-income settings. We employed 22 real-time PCR assays and retrospectively reanalyzed 610 nasopharyngeal aspirate specimens from children aged 2 to 35 months with severe pneumonia (WHO definition) admitted to Kanti Childrens' Hospital in Kathmandu, Nepal, from January 2006 through June 2008. Previously, ≥1 of 7 viruses had been detected by multiplex reverse transcription-PCR in 30% (188/627) of cases. Reanalyzing the stored specimens, we detected ≥1 pathogens, including 18 respiratory viruses and 3 atypical bacteria, in 98.7% (602/610) of cases. Rhinovirus (RV) and respiratory syncytial virus (RSV) were the most common, detected in 318 (52.1%) and 299 (49%) cases, respectively, followed by adenovirus (AdV) (10.6%), human metapneumovirus (hMPV) (9.7%), parainfluenza virus type 3 (8.4%), and enterovirus (7.7%). The remaining pathogens were each detected in less than 5%. Mycoplasma pneumoniae was most common among the atypical bacteria (3.7%). Codetections were observed in 53.3% of cases. Single-virus detection was more common for hMPV (46%) and RSV (41%) than for RV (22%) and AdV (6%). The mean cycle threshold value for detection of each pathogen tended to be lower in single-pathogen detections than in codetections. This finding was significant for RSV, RV, and AdV. RSV outbreaks occurred at the end of the monsoon or during winter. An expanded diagnostic PCR panel substantially increased the detection of respiratory viruses in young Nepalese children hospitalized with severe pneumonia. IMPORTANCE Respiratory viruses are an important cause of respiratory tract infections in children but are underrecognized as a cause of pneumonia hospitalization in low-income settings. Previously, we detected at least one of seven respiratory viruses by PCR in 30% of young Nepalese children hospitalized with severe pneumonia over a period of 36 months. Using updated PCR assays detecting 21 different viruses and atypical bacteria, we reanalyzed 610 stored upper-respiratory specimens from these children. Respiratory viruses were detected in nearly all children hospitalized for pneumonia. RSV and rhinovirus were the predominant pathogens detected. Detection of two or more pathogens was observed in more than 50% of the pneumonia cases. Single-virus detection was more common for human metapneumovirus and RSV than for rhinovirus and adenovirus. The concentration of virus was higher (low cycle threshold [CT] value) for single detected pathogens, hinting at a high viral load as a marker of clinical significance.

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.

Influenza Viral Infections Surveillance and Clinical Presentations in Hospitalized Children: A Cross-sectional Study

Background:

Influenza virus and other respiratory viruses have been identified as an essential cause of acute respiratory infections (ARIs) in children worldwide. However, there are few data on its frequency and clinical presentation in Jordan.

Objectives:

We aimed to identify the viral etiology of acute respiratory infections and the various clinical presentations in hospitalized children, especially those with influenza viruses compared to other respiratory viruses.

Methods:

A retrospective study was conducted at the Jordan University Hospital. All the positive nasopharyngeal aspirates that were collected from hospitalized children aged 0-19 years from January 2017 to January 2019 were reviewed.

Results:

A total of 338 nasopharyngeal aspirates (NPAs) with positive viral serology results were reviewed. Among the patients younger than four years, the RSV virus was the most frequently detected. However, the Influenza B virus was the most commonly seen in patients older than 5 years, H1N1 was more frequent in autumn (29.5%), and RSV was the most frequent virus in winter. Bronchopneumonia was the most frequent diagnosis among all hospitalized patients, followed by bronchiolitis. Out of 338 patients, 50.3% had tachypnea, 70.7% of patients were admitted to the pediatric floor, while 18.6% presented with a severe illness and required admission to the pediatric intensive care unit (PICU). Infants under the age of one were more likely to have higher co-infection rates with other viruses compared to children over five years that had influenza.

Conclusion:

Presentations of influenza and other respiratory viruses vary between different age groups, such as sepsis in children younger than one year.

Bacterial pneumonia and its associated factors in children from a developing country: A prospective cohort study

Introduction

Pneumonia in children is a common disease yet determining its aetiology remains elusive.

Objectives

To determine the a) aetiology, b) factors associated with bacterial pneumonia and c) association between co-infections (bacteria + virus) and severity of disease, in children admitted with severe pneumonia.

Methods

A prospective cohort study involving children aged 1-month to 5-years admitted with very severe pneumonia, as per the WHO definition, over 2 years. Induced sputum and blood obtained within 24 hrs of admission were examined via PCR, immunofluorescence and culture to detect 17 bacteria/viruses. A designated radiologist read the chest radiographs.

Results

Three hundred patients with a mean (SD) age of 14 (±15) months old were recruited. Significant pathogens were detected in 62% of patients (n = 186). Viruses alone were detected in 23.7% (n = 71) with rhinovirus (31%), human metapneumovirus (HMP) [22.5%] and respiratory syncytial virus (RSV) [16.9%] being the commonest. Bacteria alone was detected in 25% (n = 75) with Haemophilus influenzae (29.3%), Staphylococcus aureus (24%) and Streptococcus pneumoniae (22.7%) being the commonest. Co-infections were seen in 13.3% (n = 40) of patients. Male gender (AdjOR 1.84 [95% CI 1.10, 3.05]) and presence of crepitations (AdjOR 2.27 [95% CI 1.12, 4.60]) were associated with bacterial infection. C-reactive protein (CRP) [p = 0.007]) was significantly higher in patients with co-infections but duration of hospitalization (p = 0.77) and requirement for supplemental respiratory support (p = 0.26) were not associated with co-infection.

Conclusions

Bacteria remain an important cause of very severe pneumonia in developing countries with one in four children admitted isolating bacteria alone. Male gender and presence of crepitations were significantly associated with bacterial aetiology. Co-infection was associated with a higher CRP but no other parameters of severe clinical illness.

Paediatric use of antibiotics in children with community acquired pneumonia: A survey from Da Nang, Vietnam

AIM

To characterise paediatricians' antibiotic-prescribing behaviour when managing community acquired pneumonia.

METHODS

We conducted a knowledge and attitudes survey of paediatric doctors practicing at a regional provincial hospital in central Vietnam over a 2-week period (from 12 December 2017 to 29 December 2017).

RESULTS

Of 79 eligible paediatric doctors, 69 (87.3%) completed the questionnaire, of whom 65 (94.2%) thought that antibiotics were overused in Vietnam. Thirty-eight doctors (55.1%) indicated that they routinely hospitalised children with pneumonia to provide intravenous antibiotics. Most doctors reported discharging children with non-severe pneumonia after 5 days (76.9%) and those with severe pneumonia after 7-10 days (88.4%); older doctors generally continued intravenous antibiotics for longer. The two most important factors driving discharge decisions were clinical assessment (95.6%) and completion of the full course of intravenous antibiotics (80.0%). Antibiotic prescription was influenced by local guidelines (62.3%), drugs used before admission (50.0%) and the opinion of senior clinicians (37.7%). Most doctors believed antibiotic stewardship was necessary (98.6%) and that over-the-counter use of antibiotics should be restricted (97.1%).

CONCLUSIONS

Paediatricians recognised an urgent need for more effective regulation and antibiotic stewardship in Vietnam. Routinely completing a full course of intravenous antibiotics leads to unnecessary and prolonged hospitalisation.

Characterisation of children hospitalised with pneumonia in central Vietnam: a prospective study

Pneumonia is the most common reason for paediatric hospital admission in Vietnam. The potential value of using the World Health Organization (WHO) case management approach in Vietnam has not been documented.We performed a prospective descriptive study of all children (2-59 months) admitted with "pneumonia" (as assessed by the admitting clinician) to the Da Nang Hospital for Women and Children to characterise their disease profiles and assess risk factors for an adverse outcome. The disease profile was classified using WHO pneumonia criteria, with tachypnoea or chest indrawing as defining clinical signs. Adverse outcome was defined as death, intensive care unit admission, tertiary care transfer or hospital stay >10 days.Of 4206 admissions, 1758 (41.8%) were classified as "no pneumonia" using WHO criteria and only 252 (6.0%) met revised criteria for "severe pneumonia". The inpatient death rate was low (0.4% of admissions) with most deaths (11 out of 16; 68.8%) occurring in the "severe pneumonia" group. An adverse outcome was recorded in 18.7% of all admissions and 60.7% of the "severe pneumonia" group. Children were hospitalised for a median of 7 days at an average cost of 253 USD per admission. Risk factors for adverse outcome included WHO-classified "severe pneumonia", age <1 year, low birth weight, previous recent admission with an acute respiratory infection and recent tuberculosis exposure. Breastfeeding, day-care attendance and pre-admission antibiotic use were associated with reduced risk.Few hospital admissions met WHO criteria for "severe pneumonia", suggesting potential unnecessary hospitalisation and use of intravenous antibiotics. Better characterisation of the underlying diagnosis requires careful consideration.

Induced Sputum as a Diagnostic Tool in Pneumonia in Under Five Children-A Hospital-based Study

OBJECTIVE

The objective of this articlewas to study the success, tolerability of sputum induction and the bacterial isolates of induced sputum in children aged <5 years.

METHODS

The cross-sectional study included 120 hospitalized children aged 1-59 months meeting WHO criteria for pneumonia. Sputum induction was performed using hypertonic (3%) saline.

RESULTS

Mean age of the subjects was 19.5 months (2-59 months). Overall success of sputum induction was 53.3% and highest (64.28%) in 37-59 months age group. Adverse events such as tachypnea, hypoxemia (SpO2 <90) and vomiting were observed in 41.6, 17.5 and 15.8%, respectively. A potential pathogen was isolated in 45 (70.3%) of 64 cases with good quality sputum. Klebsiella pneumoniae was the commonest (38.2%) followed by Streptococcus pneumoniae (14.8%) and others.

CONCLUSION

Sputum induction in young children is safe and feasible in Indian settings. While the success was limited, bacterial yield was high.

Radiographic and CT Features of Viral Pneumonia

Viruses are the most common causes of respiratory infection. The imaging findings of viral pneumonia are diverse and overlap with those of other nonviral infectious and inflammatory conditions. However, identification of the underlying viral pathogens may not always be easy. There are a number of indicators for identifying viral pathogens on the basis of imaging patterns, which are associated with the pathogenesis of viral infections. Viruses in the same viral family share a similar pathogenesis of pneumonia, and the imaging patterns have distinguishable characteristics. Although not all cases manifest with typical patterns, most typical imaging patterns of viral pneumonia can be classified according to viral families. Although a definite diagnosis cannot be achieved on the basis of imaging features alone, recognition of viral pneumonia patterns may aid in differentiating viral pathogens, thus reducing the use of antibiotics. Recently, new viruses associated with recent outbreaks including human metapneumovirus, severe acute respiratory syndrome coronavirus, and Middle East respiratory syndrome coronavirus have been discovered. The imaging findings of these emerging pathogens have been described in a few recent studies. This review focuses on the radiographic and computed tomographic patterns of viral pneumonia caused by different pathogens, including new pathogens. Clinical characteristics that could affect imaging, such as patient age and immune status, seasonal variation and community outbreaks, and pathogenesis, are also discussed. The first goal of this review is to indicate that there are imaging features that should raise the possibility of viral infections. Second, to help radiologists differentiate viral infections, viruses in the same viridae that have similar pathogenesis and can have similar imaging characteristics are shown. By considering both the clinical and radiologic characteristics, radiologists can suggest the diagnosis of viral pneumonia. ^©RSNA, 2018.

Childhood community-acquired pneumonia: A review of etiology- and antimicrobial treatment studies

Community acquired pneumonia (CAP) is a leading cause of childhood morbidity worldwide. Because of the rising antimicrobial resistance rates and adverse effects of childhood antibiotic use on the developing microbiome, rational prescribing of antibiotics for CAP is important. This review summarizes and critically reflects on the available evidence for the epidemiology, etiology and antimicrobial management of childhood CAP. Larger prospective studies on antimicrobial management derive mostly from low- or middle-income countries as they have the highest burden of CAP. Optimal antimicrobial management depends on the etiology, age, local vaccination policies and resistance patterns. As long as non-rapid surrogate markers are used to distinguish viral- from bacterial pneumonia, the management is probably suboptimal. For a young child with signs of non-severe pneumonia (with or without wheezing), watchful waiting is recommended because of probable viral etiology. For children with more severe CAP with fever, a five-day oral amoxicillin course would be the first choice therapy and dosage will depend on local resistance rates. There is no clear evidence yet for superiority of a macrolide-based regimen for all ages. For cases with CAP requiring hospitalization, several studies have shown that narrow-spectrum IV beta-lactam therapy is as effective as a broad-spectrum cephalosporin therapy. For most severe disease, broad-spectrum therapy with or without a macrolide is suggested. In case of empyema, rapid IV-to-oral switch seems to be equivalent to prolonged IV treatment.

Limited Utility of Polymerase Chain Reaction in Induced Sputum Specimens for Determining the Causes of Childhood Pneumonia in Resource-Poor Settings: Findings From the Pneumonia Etiology Research for Child Health (PERCH) Study

Background.

Sputum examination can be useful in diagnosing the cause of pneumonia in adults but is less well established in children. We sought to assess the diagnostic utility of polymerase chain reaction (PCR) for detection of respiratory viruses and bacteria in induced sputum (IS) specimens from children hospitalized with severe or very severe pneumonia.

Methods.

Among children aged 1–59 months, we compared organism detection by multiplex PCR in IS and nasopharyngeal/oropharyngeal (NP/OP) specimens. To assess whether organism presence or density in IS specimens was associated with chest radiographic evidence of pneumonia (radiographic pneumonia), we compared prevalence and density in IS specimens from children with radiographic pneumonia and children with suspected pneumonia but without chest radiographic changes or clinical or laboratory findings suggestive of pneumonia (nonpneumonia group).

Results.

Among 4232 cases with World Health Organization–defined severe or very severe pneumonia, we identified 1935 (45.7%) with radiographic pneumonia and 573 (13.5%) with nonpneumonia. The organism detection yield was marginally improved with IS specimens (96.2% vs 92.4% for NP/OP specimens for all viruses combined [P = .41]; 96.9% vs 93.3% for all bacteria combined [P = .01]). After accounting for presence in NP/OP specimens, no organism was detected more frequently in the IS specimens from the radiographic pneumonia compared with the nonpneumonia cases. Among high-quality IS specimens, there were no statistically significant differences in organism density, except with cytomegalovirus, for which there was a higher quantity in the IS specimens from cases with radiographic pneumonia compared with the nonpneumonia cases (median cycle threshold value, 27.9 vs 28.5, respectively; P = .01).

Conclusions.

Using advanced molecular methods with IS specimens provided little additional diagnostic information beyond that obtained with NP/OP swab specimens.

Safety of Induced Sputum Collection in Children Hospitalized With Severe or Very Severe Pneumonia

Background.

Induced sputum (IS) may provide diagnostic information about the etiology of pneumonia. The safety of this procedure across a heterogeneous population with severe pneumonia in low- and middle-income countries has not been described.

Methods.

IS specimens were obtained as part a 7-country study of the etiology of severe and very severe pneumonia in hospitalized children <5 years of age. Rigorous clinical monitoring was done before, during, and after the procedure to record oxygen requirement, oxygen saturation, respiratory rate, consciousness level, and other evidence of clinical deterioration. Criteria for IS contraindications were predefined and serious adverse events (SAEs) were reported to ethics committees and a central safety monitor.

Results.

A total of 4653 IS procedures were done among 3802 children. Thirteen SAEs were reported in relation to collection of IS, or 0.34% of children with at least 1 IS specimen collected (95% confidence interval, 0.15%–0.53%). A drop in oxygen saturation that required supplemental oxygen was the most common SAE. One child died after feeding was reinitiated 2 hours after undergoing sputum induction; this death was categorized as “possibly related” to the procedure.

Conclusions.

The overall frequency of SAEs was very low, and the nature of most SAEs was manageable, demonstrating a low-risk safety profile for IS collection even among severely ill children in low-income-country settings. Healthcare providers should monitor oxygen saturation and requirements during and after IS collection, and assess patients prior to reinitiating feeding after the IS procedure, to ensure patient safety.

The Diagnostic Utility of Induced Sputum Microscopy and Culture in Childhood Pneumonia

BACKGROUND.

Sputum microscopy and culture are commonly used for diagnosing the cause of pneumonia in adults but are rarely performed in children due to difficulties in obtaining specimens. Induced sputum is occasionally used to investigate lower respiratory infections in children but has not been widely used in pneumonia etiology studies.

METHODS.

We evaluated the diagnostic utility of induced sputum microscopy and culture in patients enrolled in the Pneumonia Etiology Research for Child Health (PERCH) study, a large study of community-acquired pneumonia in children aged 1-59 months. Comparisons were made between induced sputum samples from hospitalized children with radiographically confirmed pneumonia and children categorized as nonpneumonia (due to the absence of prespecified clinical and laboratory signs and absence of infiltrate on chest radiograph).

RESULTS.

One induced sputum sample was available for analysis from 3772 (89.1%) of 4232 suspected pneumonia cases enrolled in PERCH. Of these, sputum from 2608 (69.1%) met the quality criterion of <10 squamous epithelial cells per low-power field, and 1162 (44.6%) had radiographic pneumonia. Induced sputum microscopy and culture results were not associated with radiographic pneumonia, regardless of prior antibiotic use, stratification by specific bacteria, or interpretative criteria used.

CONCLUSIONS.

The findings of this study do not support the culture of induced sputum specimens as a diagnostic tool for pneumonia in young children as part of routine clinical practice.

Bayesian Estimation of Pneumonia Etiology: Epidemiologic Considerations and Applications to the Pneumonia Etiology Research for Child Health Study

In pneumonia, specimens are rarely obtained directly from the infection site, the lung, so the pathogen causing infection is determined indirectly from multiple tests on peripheral clinical specimens, which may have imperfect and uncertain sensitivity and specificity, so inference about the cause is complex. Analytic approaches have included expert review of case-only results, case-control logistic regression, latent class analysis, and attributable fraction, but each has serious limitations and none naturally integrate multiple test results. The Pneumonia Etiology Research for Child Health (PERCH) study required an analytic solution appropriate for a case-control design that could incorporate evidence from multiple specimens from cases and controls and that accounted for measurement error. We describe a Bayesian integrated approach we developed that combined and extended elements of attributable fraction and latent class analyses to meet some of these challenges and illustrate the advantage it confers regarding the challenges identified for other methods.

Febrile Rhinovirus Illness During Pregnancy Is Associated With Low Birth Weight in Nepal

Background

Adverse birth outcomes, including low birth weight (LBW), defined as <2500 grams, small-for-gestational-age (SGA), and prematurity, contribute to 60%–80% of infant mortality worldwide and may be related to infections during pregnancy. The aim of this study was to assess whether febrile human rhinovirus (HRV) illness is associated with adverse birth outcomes.

Methods

Active household-based weekly surveillance was performed for respiratory illness episodes in pregnant women as part of a community-based, prospective, randomized trial of maternal influenza immunization in rural Nepal. Rhinovirus (HRV) febrile illness episodes were defined as fever plus cough, sore throat, runny nose, and/or myalgia with HRV detected on mid-nasal swab. Multivariate regression analysis evaluated the association between febrile HRV respiratory illness and adverse birth outcomes.

Results

Overall, 96 (3%) of 3693 pregnant women had HRV-positive febrile respiratory illnesses. Infants born to pregnant women with HRV febrile illness had a 1.6-fold increased risk of being LBW compared with those with non-HRV febrile illness (28 of 96 [38%] vs 109 of 458 [24%]; relative risk [RR], 1.6; 95% confidence interval [CI], 1.1–2.3). No difference in risk of LBW was observed between infants born to mothers with non-HRV febrile respiratory illness and those without respiratory illness during pregnancy (109 of 458 [24%] vs 552 of 2220 [25%], respectively; RR, 1.0; 95% CI, 0.8–1.2).

Conclusions

Febrile illness due to rhinovirus during pregnancy was associated with increased risk of LBW in a rural South Asian population. Interventions to reduce the burden of febrile respiratory illness due to rhinovirus during pregnancy may have a significant impact on LBW and subsequent infant mortality.

Rhinovirus species and clinical features in children hospitalised with pneumonia from Mozambique

Objectives

To describe the prevalence of human rhinovirus (RV) species in children hospitalised with pneumonia in Manhiça, Mozambique, and the associations between RV species and demographic, clinical and laboratory features.

Methods

Nasopharyngeal aspirates were collected from children 0 to 10 years of age (n = 277) presenting to Manhiça District Hospital with clinical pneumonia. Blood samples were collected for HIV and malaria testing, blood culture and full blood counts, and a chest X‐ray was performed. A panel of common respiratory viruses was investigated using two independent multiplex RT‐PCR assays with primers specific for each virus and viral type. RV species and genotypes were identified by seminested PCR assays, sequencing and phylogenetic tree analyses.

Results

At least one respiratory virus was identified in 206 (74.4%) children hospitalised with clinical pneumonia. RV was the most common virus identified in both HIV‐infected (17 of 38, 44.7%) and HIV‐uninfected (74 of 237, 31.2%; P = 0.100) children. RV‐A was the most common RV species identified (47 of 275, 17.0%), followed by RV‐C (35/275, 12.6%) and RV‐B (8/275, 2.9%). Clinical presentation of the different RV species was similar and overlapping, with no particular species being associated with specific clinical features.

Conclusions

RV‐A and RV‐C were the most common respiratory viruses identified in children hospitalised with clinical pneumonia in Manhiça. Clinical presentation of RV‐A and RV‐C was similar and overlapping.

Sputum Induction in Children Is Feasible and Useful in a Bustling General Hospital Practice

We prospectively studied the feasibility and effectiveness of sputum induction in obtaining good quality sputum and its subsequent bacterial yield in children with clinically suspected acute lower-respiratory-tract infection (aLRTI). Good quality sputum was collected in 89/98 (91%) patients. Sputum cultures revealed ≥1 bacterial pathogens in 22 cases (25%). Adverse events were infrequent and mild (6%). Sputum induction is feasible in young children and leads to an increased number of etiological diagnoses of aLRTI.

Enteroviruses and Rhinoviruses: Molecular Epidemiology of the Most Influenza-Like Illness Associated Viruses in Senegal

Different viruses have been identified as etiologic agents of respiratory tract infections, including severe cases. Among these, human rhinoviruses (HRVs) and human enteroviruses (HEVs) are recognized as leading causes. The present study describes the molecular epidemiology of HRVs and HEVs in Senegal over a 3-year surveillance period. From January 2012 to December 2014, nasopharyngeal and oropharyngeal swabs specimen were collected from patients with influenza-like illness (ILI). A real-time reverse transcription polymerase chain reaction was performed for HRV and HEV detection using the RV16 kit. Two regions were targeted for the molecular characterization of RVs: 5' untranslated region (5'UTR) and viral protein 4/viral protein 2 (VP4/VP2) transition region. For enteroviruses (EVs) phylogeny, VP1 gene was targeted. A total of 4,194 samples were collected. Children up to 5 years accounted for 52.9%. Among them, 1,415 (33.7%) were positive for HRV, 857 (20.4%) for HEV, and 437 cases of dual infections HRV/HEV. HRVs and HEVs were identified significantly in children aged 5 years or less. Only cough and vomiting signs were observed with significant association with viral infection. Both viruses co-circulated all year long with a marked increase of activity during rainy and cold period. All HRV types circulate in Senegal. HRV-A and C groups were the most common. HEV serotyping identified coxsackie B viruses (CBV) only. VP1 region revealed different CBV (CBV1, CBV2, CBV3, CBV4, and CBV5), echoviruses, coxsackieviruses A4-like strains and a poliovirus 2. The results suggest strong year-round respiratory picornavirus activity in children up to 5 years of age. Molecular studies identified a wide variety of RVs along with diverse EVs in samples from patients with ILI.

Prevention and Control of Childhood Pneumonia and Diarrhea

Pneumonia and diarrhea are the 2 leading infectious causes of death in children younger than 5 years worldwide, most of which occur in low- and middle-income countries (LMICs) in sub-Saharan Africa and Southern Asia. The past decade has seen large reductions in global childhood mortality, partly due to expansion of nonspecific public health interventions and vaccines against Streptococcus pneumoniae, Haemophilus influenzae, and rotavirus in LMICs. Further progress in this field depends on the international community's commitment to fund and implement programs using currently available vaccines and development of new vaccines against pathogens common to children in LMICs.

Molecular Epidemiology of Human Rhinoviruses and Enteroviruses Highlights Their Diversity in Sub-Saharan Africa

Human rhinoviruses (HRVs) and enteroviruses (HEVs) belong to the Enterovirus genus and are the most frequent cause of infection worldwide, but data on their molecular epidemiology in Africa are scarce. To understand HRV and HEV molecular epidemiology in this setting, we enrolled febrile pediatric patients participating in a large prospective cohort assessing the causes of fever in Tanzanian children. Naso/oropharyngeal swabs were systematically collected and tested by real-time RT-PCR for HRV and HEV. Viruses from positive samples were sequenced and phylogenetic analyses were then applied to highlight the HRV and HEV types as well as recombinant or divergent strains. Thirty-eight percent (378/1005) of the enrolled children harboured an HRV or HEV infection. Although some types were predominant, many distinct types were co-circulating, including a vaccinal poliovirus, HEV-A71 and HEV-D68. Three HRV-A recombinants were identified: HRV-A36/HRV-A67, HRV-A12/HRV-A67 and HRV-A96/HRV-A61. Four divergent HRV strains were also identified: one HRV-B strain and three HRV-C strains. This is the first prospective study focused on HRV and HEV molecular epidemiology in sub-Saharan Africa. This systematic and thorough large screening with careful clinical data management confirms the wide genomic diversity of these viruses, brings new insights about their evolution and provides data about associated symptoms.

Etiology of community acquired pneumonia among children in India: prospective, cohort study

Background

Childhood community acquired pneumonia (CAP) is a significant problem in developing countries, and confirmation of microbial etiology is important for individual, as well as public health. However, there is paucity of data from a large cohort, examining multiple biological specimens for diverse pathogens (bacteria and viruses). The Community Acquired Pneumonia Etiology Study (CAPES) was designed to address this knowledge gap.

Methods

We enrolled children with CAP (based on WHO IMCI criteria of tachypnea with cough or breathing difficulty) over 24 consecutive months, and recorded presenting symptoms, risk factors, clinical signs, and chest radiography. We performed blood and nasopharyngeal aspirate (NPA) bacterial cultures, and serology (Mycoplasma pneumoniae, Chlamydophila pneumoniae). We also performed multiplex PCR for 25 bacterial/viral species in a subgroup representing 20% of the cohort. Children requiring endotracheal intubation underwent culture and PCR of bronchoalveolar lavage (BAL) specimens.

Findings

We enrolled 2345 children. NPA and blood cultures yielded bacteria in only 322 (13.7%) and 49 (2.1%) children respectively. In NPA, Streptococcus pneumoniae (79.1%) predominated, followed by Haemophilus influenzae (9.6%) and Staphylococcus aureus (6.8%). In blood, S. aureus (30.6%) dominated, followed by S. pneumoniae (20.4%) and Klebsiella pneumoniae (12.2%). M. pneumoniae and C. pneumoniae serology were positive in 4.3% and 1.1% respectively. Multiplex PCR in 428 NPA specimens identified organisms in 422 (98.6%); of these 352 (82.2%) had multiple organisms and only 70 (16.4%) had a single organism viz. S. pneumoniae: 35 (50%), Cytomegalovirus (CMV): 13 (18.6%), Respiratory Syncytial Virus (RSV): 9 (12.9%), other viruses: 6 (8.7%), S. aureus: 5 (7.1%), and H. influenzae: 2 (2.9%). BAL PCR (n = 30) identified single pathogens in 10 (S. pneumoniae–3, CMV–3, S. aureus–2, H. influenzae–2) and multiple pathogens in 18 children. There were 108 (4.6%) deaths. The pattern of pathogens identified did not correlate with pneumonia severity or mortality.

Conclusions

The majority of children with CAP have multiple pathogens (bacteria and viruses). S. pneumoniae and S. aureus predominate in NPA and blood respectively. CMV and RSV were the dominant respiratory viruses in NPA and BAL. The presence of multiple pathogens, especially organisms associated with nasopharyngeal carriage, precludes confirmation of a causal relationship in most cases.

Association of respiratory viruses with outcomes of severe childhood pneumonia in Botswana

BACKGROUND

The highest incidence of childhood acute lower respiratory tract infection (ALRI) is in low- and middle-income countries. Few studies examined whether detection of respiratory viruses predicts ALRI outcomes in these settings.

METHODS

We conducted prospective cohort and case-control studies of children 1-23 months of age in Botswana. Cases met clinical criteria for pneumonia and were recruited within six hours of presentation to a referral hospital. Controls were children without pneumonia matched to cases by primary care clinic and date of enrollment. Nasopharyngeal specimens were tested for respiratory viruses using polymerase chain reaction. We compared detection rates of specific viruses in matched case-control pairs. We examined the effect of respiratory syncytial virus (RSV) and other respiratory viruses on pneumonia outcomes.

RESULTS

Between April 2012 and August 2014, we enrolled 310 cases, of which 133 had matched controls. Median ages of cases and controls were 6.1 and 6.4 months, respectively. One or more viruses were detected from 75% of cases and 34% of controls. RSV and human metapneumovirus were more frequent among cases than controls, but only enterovirus/rhinovirus was detected from asymptomatic controls. Compared with non-RSV viruses, RSV was associated with an increased risk of treatment failure at 48 hours [risk ratio (RR): 1.85; 95% confidence interval (CI): 1.20, 2.84], more days of respiratory support [mean difference (MD): 1.26 days; 95% CI: 0.30, 2.22 days], and longer duration of hospitalization [MD: 1.35 days; 95% CI: 0.20, 2.50 days], but lower in-hospital mortality [RR: 0.09; 95% CI: 0.01, 0.80] in children with pneumonia.

CONCLUSIONS

Respiratory viruses were detected from most children hospitalized with ALRI in Botswana, but only RSV and human metapneumovirus were more frequent than among children without ALRI. Detection of RSV from children with ALRI predicted a protracted illness course but lower mortality compared with non-RSV viruses.

Is virus coinfection a predictor of severity in children with viral respiratory infections?

Molecular assays have resulted in increased detection of viral respiratory infections, including virus coinfection, from children with acute respiratory infections. Yet the clinical severity of virus coinfection compared to single virus infection remains uncertain. We performed a retrospective study of children presenting with acute respiratory infections comparing clinical severity of single respiratory virus infection to virus coinfection, detected on midturbinate swabs by molecular assays. Patient characteristics and measures of clinical severity were abstracted from health records. A total of 472 virus-infected children were included, 391 with a single virus infection and 81 with virus coinfection. Virus status did not affect admission to hospital (odds ratio (OR) = 0.8; 95 % confidence interval (CI) 0.5–1.4; p 0.491) or clinical disease severity among inpatients (OR = 0.8; 95% CI 0.5–1.5; p 0.515) after adjusting for age and underlying comorbidities. However, children infected with rhinovirus/enterovirus (HRV/ENT) alone were more likely to be admitted to the hospital compared to those coinfected with HRV/ENT and at least another virus, although this was not significant in multivariable analyses (OR 0.47; 95% CI 0.22–1.0; p 0.051). In multivariable analyses, children coinfected with respiratory syncytial virus (RSV) and other viruses were significantly more likely to present with radiologically confirmed pneumonia compared to those with an isolated RSV infection (OR 3.16, 95% CI 1.07–9.34, p 0.037). Equivalent clinical severity was observed between children with single virus infection and virus coinfection, although children coinfected with RSV and other viruses presented more frequently with pneumonia than those with single RSV infection. Increased disease severity observed among children with single HRV/ENT infection requires further investigation.

Prospective study of maternal alcohol intake during pregnancy or lactation and risk of childhood asthma: the Norwegian Mother and Child Cohort Study

BACKGROUND

Many women drink during pregnancy and lactation despite recommendations to abstain. In animals, alcohol exposure during pregnancy and lactation influences lung and immune development, plausibly increasing risk of asthma and lower respiratory tract infections (LRTIs). Studies in humans are few.

METHODS

In the Norwegian Mother and Child Cohort Study, we examined maternal alcohol intake during pregnancy and lactation in relation to risk of current asthma at 36 months (49,138 children), recurrent LRTIs by 36 months (39,791 children), and current asthma at 7 years (13,253 children). Mothers reported frequency and amount of alcohol intake each trimester and the first 3 months following delivery. We calculated adjusted relative risk (aRR), comparing children of drinkers to nondrinkers, using Generalized Linear Models.

RESULTS

A total of 31.8% of mothers consumed alcohol during first trimester, 9.7% during second trimester, and 15.6% during third trimester. Infrequent and low-dose prenatal alcohol exposure showed a modest statistically significant inverse association with current asthma at 36 months (aRRs ~ 0.85). No association was seen with the highest alcohol intakes during the first trimester when alcohol consumption was most common. RRs of maternal alcohol intake during pregnancy with recurrent LRTIs were ~1, with sporadic differences in risk for some metrics of intake, but without any consistent pattern. For current asthma at 7 years, similar inverse associations were seen as with current asthma at 36 months but were not statistically significant. Among children breastfed throughout the first 3 months of life, maternal alcohol intake during this time was not significantly associated with any of the 3 outcomes.

CONCLUSIONS

The low levels of alcohol exposure during pregnancy or lactation observed in this cohort were not associated with increased risk of asthma or recurrent LRTIs. The slight inverse associations of infrequent or low-dose prenatal alcohol exposure with asthma may not be causal.

50 years of pediatric pulmonology, progress and future

Development of Pediatric Pulmonology as a speciality in India is steadily improving over past few decades. Present profile of Indian pediatric chest services include: asthma, recurrent infections, bronchiectasis, etc. It is expected to change and the emerging pulmonary illnesses include: human immunodeficiency virus (HIV infection) associated pulmonary illnesses, cystic fibrosis, primary ciliary dyskinesia, bronchopulmonary dysplasia, interstitial lung diseases, gastroesophageal reflux diseases, neuromuscular illnesses, sleep disorders, disorders due to malformations and opportunistic pulmonary infections. Respiratory infections constitute major load in pediatric outpatient services and are the leading cause of mortality in under-five children. To reduce morbidity and mortality due to respiratory tract infections, Indian Academy of Pediatrics (IAP) has developed Respiratory Tract Infection Group Education Module (RTIGEMS). After initial increase in prevalence of asthma, it seems to have stabilized now but going by the numbers, it will remain a major health problem in India. Diagnosis of pulmonary tuberculosis was always a challenge to pediatricians and with emergence of drug resistant tuberculosis, it is even more challenging. Presently few centers are providing specialized Pediatric pulmonology services in India. There is a need to develop more centers to enhance services including (a) assessment of pulmonary physiology by performing pulmonary function testing in all age groups, (b) improving diagnostic and therapeutic role of bronchoscopy and bronchoalveolar lavage, (c) sweat testing, (d) molecular diagnostics for various respiratory illnesses, and (e) utilizing advance imaging and minimally invasive technologies for diagnosis and treatment of respiratory illnesses. At present there is no degree course in Pediatric Pulmonology in India. Initially middle level pediatricians wanting to pursue their career in pediatric pulmonology should undergo training in existing centers. Trained persons should develop a network to collect data and answer relevant research questions.

Phylogenetic analysis of human rhinovirus isolates collected from otherwise healthy children with community-acquired pneumonia during five successive years

In order to evaluate the circulation of the different human rhinovirus (HRV) species and genotypes in Italian children with radiographically confirmed community-acquired pneumonia (CAP), a nasopharyngeal swab was obtained from 643 children admitted to hospital because of CAP during five consecutive winter and early spring seasons (2007-2012). Real-time reverse transcriptase polymerase chain reaction (RT-PCR) was used to identify HRV, and the HRV-positive samples were used for sequencing analysis and to reconstruct the phylogenetic tree. HRV was identified in 198 samples (42.2%), and the VP4/VP2 region was successfully amplified in 151 (76.3%). HRV-A was identified in 78 samples (51.6%), HRV-B in 14 (9.3%) and HRV-C in 59 (39.1%). Forty-seven (31.1%) of the children with HRV infection were aged <1 year, 71 (47.0%) were aged 1-3 years, and 33 (21.9%) were aged ≥4 years. Blast and phylogenetic analyses showed that the HRV strains were closely related to a total of 66 reference genotypes, corresponding to 29 HRV-A, 9 HRV-B and 28 HRV-C strains. Nucleotide variability was 37% between HRV-A and HRV-B, 37.3% between HRV-A and HRV-C, and 39.9% between HRV-B and HRV-C. A number of sequences clustered with known serotypes and, within these clusters, there were strains circulating during several seasons. The most frequently detected genotypes were HRV-A78 (n=17), HRV-A12 (n=9) and HRV-C2 (n=5). This study shows that, although it is mainly associated with HRV-A, pediatric CAP can also be diagnosed in subjects infected by HRV-C and, more rarely, by HRV-B. Moreover, a large number of genotypes may be involved in causing pediatric CAP and can be different from year to year. Although the prolonged circulation of the same genotypes can sometimes be associated with a number of CAP episodes in different years.

Prevalence of herpes and respiratory viruses in induced sputum among hospitalized children with non typical bacterial community-acquired pneumonia

Objective

Few comprehensive studies have searched for viruses in infants and young children with community-acquired pneumonia (CAP) in China. The aim of this study was to investigate the roles of human herpes viruses (HHVs) and other respiratory viruses in CAP not caused by typical bacterial infection and to determine their prevalence and clinical significance.

Methods

Induced sputum (IS) samples were collected from 354 hospitalised patients (infants, n = 205; children, n = 149) with respiratory illness (CAP or non-CAP) admitted to Wenling Hospital of China. We tested for HHVs and respiratory viruses using PCR-based assays. The epidemiological profiles were also analysed.

Results

High rate of virus detection (more than 98%) and co-infection (more than 80%) were found among IS samples from 354 hospitalised infants and children with respiratory illness in this study. Of 273 CAP samples tested, CMV (91.6%), HHV-6 (50.9%), RSV (37.4%), EBV (35.5%), HBoV (28.2%), HHV-7 (18.3%) and rhinovirus (17.2%) were the most commonly detected viruses. Of 81 non- CAP samples tested, CMV (63%), RSV (49.4%), HHV-6 (42%), EBV (24.7%), HHV-7 (13.6%) and HBoV (8.6%) were the dominant viruses detected. The prevalence of several viral agents (rhinovirus, bocavirus, adenovirus and CMV) among IS samples of CAP were significantly higher than that of non-CAP control group. We also found the prevalence of RSV coinfection with HHVs was also higher among CAP group than that of non-CAP control.

Conclusions

With sensitive molecular detection techniques and IS samples, high rates of viral identification were achieved in infants and young children with respiratory illness in a rural area of China. The clinical significance of rhinovirus, bocavirus, adenovirus and HHV (especially CMV) infections should receive greater attention in future treatment and prevention studies of CAP in infants and children.

Narrow vs broad-spectrum antimicrobial therapy for children hospitalized with pneumonia

BACKGROUND

The 2011 Pediatric Infectious Diseases Society/Infectious Diseases Society of America community-acquired pneumonia (CAP) guideline recommends narrow-spectrum antimicrobial therapy for most children hospitalized with CAP. However, few studies have assessed the effectiveness of this strategy.

METHODS

Using data from 43 children's hospitals, we conducted a retrospective cohort study to compare outcomes and resource utilization among children hospitalized with CAP between 2005 and 2011 receiving either parenteral ampicillin/penicillin (narrow spectrum) or ceftriaxone/cefotaxime (broad spectrum). Children with complex chronic conditions, interhospital transfers, recent hospitalization, or the occurrence of any of the following during the first 2 calendar days of hospitalization were excluded: pleural drainage procedure, admission to intensive care, mechanical ventilation, death, or hospital discharge.

RESULTS

Overall, 13,954 children received broad-spectrum therapy (89.7%) and 1610 received narrow-spectrum therapy (10.3%). The median length of stay was 3 days (interquartile range 3-4) in the broad- and narrow-spectrum therapy groups (adjusted difference 0.12 days, 95% confidence interval [CI]: -0.02 to 0.26). One hundred fifty-six children (1.1%) receiving broad-spectrum therapy and 13 children (0.8%) receiving narrow-spectrum therapy were admitted to intensive care (adjusted odds ratio 0.85, 95% CI: 0.27 to 2.73). Readmission occurred for 321 children (2.3%) receiving broad-spectrum therapy and 39 children (2.4%) receiving narrow-spectrum therapy (adjusted odds ratio 0.85, 95% CI: 0.45 to 1.63). Median costs for the hospitalization were $3992 and $4375 (adjusted difference -$14.4, 95% CI: -177.1 to 148.3).

CONCLUSIONS

Clinical outcomes and costs for children hospitalized with CAP are not different when treatment is with narrow- compared with broad-spectrum therapy.

Addressing the public health burden of respiratory viruses: the Battle against Respiratory Viruses (BRaVe) Initiative

Given the enormous estimated burden of respiratory virus infections worldwide, a substantial number of research priorities exist in order to better understand their epidemiology, pathogenesis, prevention and clinical management across different populations and resource settings. New therapeutics and specific vaccines for noninfluenza respiratory virus infections could provide enormous benefits in reducing the morbidity and mortality associated with these frequent infections and provide the foundation for responding to newly emerging threats. The BRaVe Initiative is a new WHO-led effort to catalyze multidisciplinary research on strategies to prevent and treat medically important respiratory virus infections with the goal of timely integration of scientific advances and technical innovations into public health practice.

Clinical characteristics and outcomes of influenza and other influenza-like illnesses in Mexico City

BACKGROUND

Influenza-like illnesses (ILI) are estimated to cause millions of deaths annually. Despite this disease burden, the etiologic causes of ILI are poorly described for many geographical regions.

METHODS

Beginning in April 2010, we conducted an observational cohort study at five hospitals in Mexico City, enrolling subjects who met the criteria for ILI. Evaluations were conducted at enrollment and on day 28, with the collection of clinical data and a nasopharyngeal swab (or nasal aspirate in children). Swabs were tested by multiplex PCR for 15 viral pathogens and real-time PCR for influenza.

RESULTS

During the first year, 1065 subjects were enrolled in this study, 55% of whom were hospitalized; 24% of all subjects were children. One or more pathogens were detected by PCR in 64% of subjects, most commonly rhinovirus (25% of all isolates) and influenza (24% of isolates). Six percent of subjects died, and of those, 54% had no pathogen identified. Rhinovirus was the most common pathogen among those who died, although it did not have the highest case fatality rate.

CONCLUSIONS

Multiple respiratory viruses beyond influenza are associated with significant morbidity and mortality among adults and children in Mexico City. Detection of these agents could be useful for the adjustment of antibiotic treatment in severe cases.

Vaccines as a tool to estimate the burden of severe influenza in children of low-resourced areas (November 30-December 1, 2012, Les Pensieres, Veyrier-du-Lac, France)

There is an increasing focus on influenza in low-resourced areas as a vaccine-preventable cause of severe lower respiratory disease in young children, especially among those under two years of age. The extent of the disease burden is unclear: current etiologic studies may underestimate the impact of influenza if recognized or unrecognized infection occurs some time before severe disease manifestations prompt specimen collection for diagnosis. Because of various methodological challenges, a vaccine probe approach was used to estimate vaccine preventable disease incidence (VPDI) for Streptococcus pneumoniae and Haemophilus influenzae type b, particularly for pneumonia outcomes among young children. A similar approach could be used to determine VPDI for influenza. A highly effective vaccine would facilitate this approach; however, with appropriate design, a less than ideal vaccine also could be used to estimate VPDI. Because influenza vaccine efficacy against severe disease may be greater than against all symptomatic influenza disease, a vaccine probe approach could provide a better measure than etiologic studies of the public health utility of influenza vaccine. The first 6 months of life is a time of particularly increased influenza risk among young children, and an age group for which current vaccines are not approved. Previous studies have found that maternal influenza immunization can reduce acute respiratory infection in the infant during this vulnerable period. Additional randomized, controlled trials are currently underway using a vaccine probe approach to estimate VPDI among mothers and their infants following maternal influenza immunization. The World Health Organization now identifies pregnant women as the highest priority target group for influenza vaccination. Should countries implement this strategy, infants age 6-23 months likely would remain at increased risk; vaccine probe approaches could quantify the public health benefit of immunizing this group.

Prospects for molecular point-of-care diagnosis of lower respiratory infections at the hospital’s doorstep

Now that molecular assays have been simplified, they can be performed at the point of care (POC). As we aimed to evaluate POC detection of respiratory viruses, we have collected studies on the molecular detection of viruses in children and adults with a well-characterized diagnosis, made in hospital settings, of community-acquired acute bronchiolitis (AB) or pneumonia (CAP). We then present the epidemiological issues for each disease. The prevalence of 18 virus species and types was determined separately for each disease, virus by virus. Overall, the median detection rate of viruses was 90% (interquartile range [IQR]: 69.25–93.5%) and 71.8% (IQR: 69.25–74.25%) in children with AB and CAP, respectively, and 24.5% (IQR: 20–30%) in adults with CAP. The observations on the relationship between virological findings and severity of disease were conflicting in AB, while those for influenza-related CAP were significantly associated with high morbidity/mortality. There is evidence supporting the suggestion that molecular POC detection of targeted pathogens could optimize bed management in emergency departments, guide anti-infective therapies and prevent nosocomial outbreaks. However, further investigations are required to determine when the detection of a large panel of viruses should be processed in clinical practice.

George K, Walsh TJ. Human rhinoviruses

Human rhinoviruses (HRVs), first discovered in the 1950s, are responsible for more than one-half of cold-like illnesses and cost billions of dollars annually in medical visits and missed days of work. Advances in molecular methods have enhanced our understanding of the genomic structure of HRV and have led to the characterization of three genetically distinct HRV groups, designated groups A, B, and C, within the genus Enterovirus and the family Picornaviridae. HRVs are traditionally associated with upper respiratory tract infection, otitis media, and sinusitis. In recent years, the increasing implementation of PCR assays for respiratory virus detection in clinical laboratories has facilitated the recognition of HRV as a lower respiratory tract pathogen, particularly in patients with asthma, infants, elderly patients, and immunocompromised hosts. Cultured isolates of HRV remain important for studies of viral characteristics and disease pathogenesis. Indeed, whether the clinical manifestations of HRV are related directly to viral pathogenicity or secondary to the host immune response is the subject of ongoing research. There are currently no approved antiviral therapies for HRVs, and treatment remains primarily supportive. This review provides a comprehensive, up-to-date assessment of the basic virology, pathogenesis, clinical epidemiology, and laboratory features of and treatment and prevention strategies for HRVs.

Community-Acquired Pneumonia in the Conjugate Vaccine Era

Community-acquired pneumonia (CAP) remains one of the most common serious infections encountered among children worldwide. In this review, we highlight important literature and recent scientific discoveries that have contributed to our current understanding of pediatric CAP. We review the current epidemiology of childhood CAP in the developed world, appraise the state of diagnostic testing for etiology and prognosis, and discuss disease management and areas for future research in the context of recent national guidelines.

Viral and atypical bacterial etiology of acute respiratory infections in children under 5 years old living in a rural tropical area of Madagascar

Background

In Madagascar, very little is known about the etiology and prevalence of acute respiratory infections (ARIs) in a rural tropical area. Recent data are needed to determine the viral and atypical bacterial etiologies in children with defined clinical manifestations of ARIs.

Methods

During one year, we conducted a prospective study on ARIs in children between 2 to 59 months in the community hospital of Ampasimanjeva, located in the south-east of Madagascar. Respiratory samples were analyzed by multiplex real-time RT-PCR, including 18 viruses and 2 atypical bacteria. The various episodes of ARI were grouped into four clinical manifestations with well-documented diagnosis: “Community Acquired Pneumonia”(CAP, group I), “Other acute lower respiratory infections (Other ALRIs, group II)”, “Upper respiratory tract infections with cough (URTIs with cough, group III)”and “Upper respiratory tract infections without cough (URTIs without cough, group IV)”.

Results

295 children were included in the study between February 2010 and February 2011. Viruses and/or atypical bacteria respiratory pathogens were detected in 74.6% of samples, the rate of co-infection was 27.3%. Human rhinovirus (HRV; 20.5%), metapneumovirus (HMPV A/B, 13.8%), coronaviruses (HCoV, 12.5%), parainfluenza virus (HPIV, 11.8%) and respiratory syncytial virus A and B (RSV A/B, 11.8%) were the most detected. HRV was predominantly single detected (23.8%) in all the clinical groups while HMPV A/B (23.9%) was mainly related to CAP (group I), HPIV (17.3%) to the “Other ALRIs” (group II), RSV A/B (19.5%) predominated in the group “URTIs with cough” (group III) and Adenovirus (HAdV, 17.8%) was mainly detected in the “without cough” (group IV).

Interpretation

This study describes for the first time the etiology of respiratory infections in febrile children under 5 years in a malaria rural area of Madagascar and highlights the role of respiratory viruses in a well clinically defined population of ARIs.

Circulation of different rhinovirus groups among children with lower respiratory tract infection in Kiremba, Burundi

The purpose of this investigation was to collect information regarding rhinovirus (RV) circulation in children with lower respiratory tract infections (LRTIs) in Burundi, Central Africa. We enrolled all of the children aged between 1 month and 14 years who were admitted to the hospital of Kiremba, North Burundi, with fever and signs and symptoms of LRTI (i.e., cough, tachypnea, dyspnea or respiratory distress, and breathing with grunting or wheezing sounds with rales) between 1 November 2010 and 31 October 2011, and obtained nasopharyngeal swabs for RV detection by means of polymerase chain reaction (PCR). The VP4/VP2 region of the positive samples was sequenced to determine the species of RV (A, B, or C). Four hundred and sixty-two children were enrolled: 160 (34.6 %) with bronchitis, 35 (7.6 %) with infectious wheezing, and 267 (57.8 %) with community-acquired pneumonia (CAP). RV infection was demonstrated in 186 patients [40.3 %; mean age ± standard deviation (SD) 1.77 ± 2.14 years]. RV infection was detected in 78 patients aged <12 months (40.0 %), 102 aged 12-48 months (44.3 %), and six aged >48 months (16.7 %; p < 0.01 vs. the other age groups). The most frequently identified RV was RV-A (81 cases, 43.5 %), followed by RV-C (47, 25.3 %) and RV-B (18, 9.7 %); subtyping was not possible in 40 cases (21.5 %). RV-A was significantly associated with bronchitis and CAP (p < 0.01) and RV-C with wheezing (p < 0.05). In Burundi, RVs are frequently detected in children with LRTIs. RV-A seems to be the most important species and is identified mainly in patients with bronchitis and CAP.