Defining the Risk and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Infants with Congenital Heart Disease

Respiratory syncytial virus immunization patterns in Germany, 2015-2020

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infection (LRTI) in infants and young children worldwide. Using routine statutory health insurance claims data including patients from all regions of Germany, we investigated the health-care resource use and costs associated with RSV prophylaxis with palivizumab in Germany. In the database, infants from the birth cohorts 2015-2019 eligible for palivizumab immunization were identified using codes of the 10th revision of the International Classification of Diseases (ICD-10). Health-care resource use and costs related to immunization were determined by inpatient and outpatient administrations. Over the study period, only 1.3% of infants received at least one dose of palivizumab in their first year of life. The mean number of doses per immunized infant was 4.6. From a third-party payer perspective, the mean costs of palivizumab per infant who received at least one dose in the first year of life was €5,435 in the birth cohorts 2015-2019. Despite the substantial risk of severe RSV infection, we found low rates of palivizumab utilization. Novel preventive interventions, featuring broader indications and single-dose administration per season, contribute to mitigating the burden of RSV disease across a more extensive infant population.

An epidemiological investigation of high-risk infants for Respiratory Syncytial Virus infections: a retrospective cohort study

BACKGROUND

Respiratory Syncytial Virus (RSV) infections may lead to severe consequences in infants born preterm with breathing problems (such as bronchopulmonary dysplasia (BPD) and respiratory distress syndrome (RDS)) or congenital heart diseases (CHD). Since studies investigating the influence of different gestational age (WGA) and concomitant specific comorbidities on the burden of RSV infections are scarce, the present study aimed to better characterize these high-risk populations in the Italian context.

METHODS

This retrospective, longitudinal and record-linkage cohort study involved infants born between 2017 and 2019 in Lazio Region (Italy) and is based on data extracted from administrative databases. Each infant was exclusively included in one of the following cohorts: (1) BPD-RDS (WGA ≤35 with or without CHD) or (2) CHD (without BPD and/or RDS) or (3) Preterm (WGA ≤35 without BPD (and/or RDS) or CHD). Each cohort was followed for 12 months from birth. Information related to sociodemographic at birth, and RSV and Undetermined Respiratory Agents (URA) hospitalizations and drug consumption at follow-up were retrieved and described.

RESULTS

A total of 8,196 infants were selected and classified as 1,084 BPD-RDS, 3,286 CHD and 3,826 Preterm. More than 30% of the BPD-RDS cohort was composed by early preterm infants (WGA ≤ 29) in contrast to the Preterm cohort predominantly constitute by moderate preterm infants (98.2%), while CHD infants were primarily born at term (83.9%). At follow-up, despite the cohorts showed similar proportions of RSV hospitalizations, in BPD-RDS cohort hospitalizations were more frequently severe compared to those occurred in the Preterm cohort (p<0.01), in the BPD-RDS cohort was also found the highest proportion of URA hospitalizations (p<0.0001). In addition, BPD-RDS infants, compared to those of the remaining cohorts, received more frequently prophylaxis with palivizumab (p<0.0001) and were more frequently treated with adrenergics inhalants, and glucocorticoids for systemic use.

CONCLUSIONS

The assessment of the study clinical outcomes highlighted that, the demographic and clinical characteristics at birth of the study cohorts influence their level of vulnerability to RSV and URA infections. As such, continuous monitoring of these populations is necessary in order to ensure a timely organization of health care system able to respond to their needs in the future.

Clinical epidemiology and disease burden of bronchiolitis in hospitalized children in China: a national cross-sectional study

BACKGROUND

Bronchiolitis is a common acute lower respiratory tract infection (ALRTI) and the most frequent cause of hospitalization of infants and young children with ALRTI. Respiratory syncytial virus is the main pathogen that leads to severe bronchiolitis. The disease burden is relatively high. To date, few descriptions of the clinical epidemiology and disease burden of children hospitalized for bronchiolitis are available. This study reports the general clinical epidemiological characteristics and disease burden of bronchiolitis in hospitalized children in China.

METHODS

This study included the face sheet of discharge medical records collected from 27 tertiary children's hospitals from January 2016 to December 2020 that were aggregated into the FUTang Update medical REcords (FUTURE) database. The sociodemographic variables, length of stay (LOS) and disease burden of children with bronchiolitis were analyzed and compared using appropriate statistical tests.

RESULTS

In total, 42,928 children aged 0-3 years were hospitalized due to bronchiolitis from January 2016 to December 2020, accounting for 1.5% of the total number of hospitalized children of the same age in the database during the period and 5.31% of the hospitalizations for ALRTI. The male to female ratio was 2.01:1. Meanwhile, more boys than girls were observed in different regions, age groups, years, and residences. The 1-2 year age group had the greatest number of hospitalizations for bronchiolitis, while the 29 days-6 months group had the largest proportion of the total inpatients and inpatients with ALRTI in the same age group. In terms of region, the hospitalization rate of bronchiolitis was the highest in East China. Overall, the number of hospitalizations from 2017 to 2020 showed a decreasing trend from that in 2016. Seasonally, the peak hospitalizations for bronchiolitis occurred in winter. Hospitalization rates in North China in autumn and winter were higher than those in South China, while hospitalization rates in South China were higher in spring and summer. Approximately, half of the patients with bronchiolitis had no complications. Among the complications, myocardial injury, abnormal liver function and diarrhea were more common. The median LOS was 6 days [interquartile range (IQR) = 5-8], and the median hospitalization cost was 758 United States dollars (IQR = 601.96-1029.53).

CONCLUSIONS

Bronchiolitis is a common respiratory disease in infants and young children in China, and it accounts for a higher proportion of both total hospitalizations and hospitalizations due to ALRTI in children. Among them, children aged 29 days-2 years are the main hospitalized population, and the hospitalization rate of boys is significantly higher than that of girls. The peak season for bronchiolitis is winter. Bronchiolitis causes few complications and has a low mortality rate, but the burden of this disease is heavy.

A Descriptive Analysis of Febrile Seizure Hospitalizations in Children with Congenital Heart Disease in the United States

BACKGROUND

Febrile seizure (FS) is the most common convulsive disorder in children. This study analyzed the national proportion of congenital heart disease (CHD) and hospital resource utilization among children admitted for FSs in the U.S.

METHODS

This is a retrospective cross-sectional analysis of pediatric patients up to six years with a primary diagnosis of FS in 2016 and 2019 using the Kids Inpatient Database (KID). The demographic, hospital, and clinical characteristics of children with and without CHD were compared using the chi-square test for categorical variables and linear regressions for continuous variables. Multivariate logistic analysis was conducted to evaluate the impact of CHD on the mean length of hospital stay.

RESULTS

An estimated 10,039 children were admitted with the primary diagnosis of FS. Out of these, 117 (1.2%) had a discharge diagnosis of CHD. The mean age for children with and without CHD was 1.4 years (SD 1.60) and 1.5 years (SD 1.501), respectively. Children with CHD who required hospitalization for FS had longer mean lengths of hospital stay (2.1 days vs. 1.6 days), with an adjusted odd ratio of 0.43 (95% CI: 0.07-0.99; p-value: 0.017). Similarly, the hospital charges for children with CHD were higher than those without CHD ($30,960.28 vs. $21,005.11).

CONCLUSION

Children with CHD who required inpatient admission for FSs in the U.S. were associated with increased length of hospital stay and higher resource utilization when compared with those without CHD. This highlights the need for preventive measures among this vulnerable population.

Respiratory Syncytial Virus Infections in Neonates: A Persisting Problem

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections in young infants. It is an enveloped, single-stranded, nonsegmented, negative-strand RNA virus, a member of the family Pneumoviridae. Globally, RSV is responsible for 2.3% of deaths among neonates 0-27 days of age. Respiratory syncytial virus infection is most common in children aged below 24 months. Neonates present with cough and fever. Respiratory syncytial virus-associated wheezing is seen in 20% infants during the first year of life of which 2-3% require hospitalization. Reverse transcriptase polymerase chain reaction (RT-PCR) gives fast results and has higher sensitivity compared with culture and rapid antigen tests and are not affected by passively administered antibody to RSV. Therapy for RSV infection of the LRT is mainly supportive, and preventive measures like good hygiene and isolation are the mainstay of management. Standard precautions, hand hygiene, breastfeeding and contact isolation should be followed for RSV-infected newborns. Recent AAP guidelines do not recommend pavilizumab prophylaxis for preterm infants born at 29-35 weeks without chronic lung disease, hemodynamically significant congenital heart disease and coexisting conditions. RSV can lead to long-term sequelae such as wheezing and asthma, associated with increased healthcare costs and reduced quality of life.

Impact of congenital heart disease on outcomes among pediatric patients hospitalized for COVID-19 infection

BACKGROUND

COVID-19 infection is generally regarded as an acute self-limiting illness in children, but it can cause significant morbidity and mortality in both healthy and high-risk children. There are limited data on the outcomes of children with congenital heart disease (CHD) and COVID-19. This study aimed to examine the risks of mortality, in-hospital cardiovascular and non-cardiovascular complications in this patient population.

METHODS

We analyzed data from hospitalized pediatric patients from 2020 using the nationally representative National Inpatient Sample (NIS). Children hospitalized for COVID-19 were included, and weighted data were used to compare in-hospital mortality and morbidities between children with and without CHD.

RESULTS

Out of 36,690 children admitted with a diagnosis of COVID-19 infection(ICD-10 code:U07.1 and B97.29) during calendar year 2020, 1240 (3.4%) had CHD. The risk of mortality in children with CHD was not significantly higher than those without CHD(1.2% vs. 0.8%, p = 0.50), with adjusted OR (aOR) of 1.7 (95% CI: 0.6-5.3). Tachyarrhythmias and heart block were more likely in CHD children with an aOR of 4.2 (95% CI: 1.8-9.9) and aOR of 5.0 (95% CI: 2.4-10.8), respectively. Similarly, respiratory failure [aOR = 2.0 (1.5-2.8)], respiratory failure requiring non-invasive mechanical ventilation [aOR = 2.7 (1.4-5.2)] and invasive mechanical ventilation [aOR = 2.6 (1.6-4.0)], and acute kidney injury [aOR = 3.4 (2.2-5.4)] were all significantly higher among patients with CHD. Median length of hospital stay in children with CHD was longer than those without CHD [5 days (IQR: 2-11) vs. 3 days (IQR: 2-5), p = < 0.001].

CONCLUSIONS

Children with CHD hospitalized with COVID-19 infection were at increased risk of serious cardiovascular and non-cardiovascular adverse clinical outcomes. They also had increased length of hospital stay and utilization of healthcare resources.

Expressions of Type I and III Interferons, Endogenous Retroviruses, TRIM28, and SETDB1 in Children with Respiratory Syncytial Virus Bronchiolitis

Interferons (IFNs) and IFN-stimulated genes (ISGs) play essential roles for the control of viral infections. Their expression in infants with respiratory syncytial virus (RSV) bronchiolitis is poorly defined. Human endogenous retroviruses (HERVs) represent 8% of our genome and modulate inflammatory and immune reactions. TRIM28 and SETDB1 participate in the epigenetic regulation of genes involved in the immune response, including IFNs and HERVs. No study has explored the expression of HERVs, TRIM28, and SETDB1 during RSV bronchiolitis. We assessed, through a PCR real-time Taqman amplification assay, the transcription levels of six IFN-I ISGs, four IFNλs, the pol genes of HERV-H, -K, and -W families, the env genes of Syncytin (SYN)1 and SYN2, and of TRIM28/SETDB1 in whole blood from 37 children hospitalized for severe RSV bronchiolitis and in healthy children (HC). The expression of most IFN-I ISGs was significantly higher in RSV+ patients than in age-matched HC, but it was inhibited by steroid therapy. The mRNA concentrations of IFN-λs were comparable between patients and age-matched HC. This lack of RSV-driven IFN-III activation may result in the defective protection of the airway mucosal surface leading to severe bronchiolitis. The expression of IFN-III showed a positive correlation with age in HC, that could account for the high susceptibility of young children to viral respiratory tract infections. The transcription levels of every HERV gene were significantly lower in RSV+ patients than in HC, while the expressions of TRIM28/SETDB1 were overlapping. Given the negative impact of HERVs and the positive effects of TRIM28/SETDB1 on innate and adaptive immune responses, the downregulation of the former and the normal expression of the latter may contribute to preserving immune functions against infection.

Prophylaxis protects infants with congenital heart disease from severe forms of RSV infection: an Italian observational retrospective study : Palivizumab prophylaxis in children with congenital heart disease

BACKGROUND

In children with congenital heart disease (CHD) respiratory syncytial virus (RSV) infection may have a severe course, with increased risk of morbidity and mortality, requiring hospital admission and intensive care. The aim of the present study was to evaluate the effect of prophylaxis with palivizumab in preventing RSV-associated hospitalization in infants with CHD.

METHODS

We carried out an observational, retrospective study in a paediatric cardiology division at a secondary-care centre in Italy, extracting from the database children with CHD who, from November 2004 to March 2022, matched the criteria for palivizumab prophylaxis, to evaluate the hospitalization rate in CHD patients with and without palivizumab prophylaxis and their RSV-related hospitalization characteristics compared with a group of children without CHD and no other underlying clinical conditions (control group, CG), hospitalized for RSV infection.

RESULTS

One hundred twenty-eight children with CHD were enrolled in the study, mainly (71.9%) with increased pulmonary flow, and received palivizumab prophylaxis. Twenty-seven received hospital care for bronchiolitis. Almost all CHD patients hospitalized for bronchiolitis (26 out of 27) received partial prophylaxis (≤ 3 doses). CHD patients with bronchiolitis stay longer in the hospital than control (14.4 ± 21.7 days vs 6.2 ± 2.3 days) some of which require intensive care (n = 4).

CONCLUSIONS

Our study provides evidence of the efficacy of palivizumab in protecting patients with hemodynamically significant CHD under the age of 2 years from RSV disease and its life-threatening complications. Reducing hospitalisation rate, morbidity, and mortality in this category of patients, passive immune prophylaxis with palivizumab may impact healthcare resource availability and utilisation.

Predicting the severity of viral bronchiolitis in children

Acute viral bronchiolitis is one of the common causes of hospitalization and mortality, especially among children in the first year of life who have risk factors (prematurity, congenital heart defects, bronchopulmonary dysplasia, immunosuppression). As factors associated with the severe course of bronchiolitis, along with the traditional ones, single nucleotide polymorphisms of the genes of the immune response molecules can be considered.The aim. Based on the analysis of clinical, laboratory and molecular genetic parameters, to identify prognostic criteria for the severe course of acute viral bronchiolitis in children.Materials and methods. The study included 106 children with acute viral bronchiolitis (severe course – 34, mild course – 72), the etiology of which in 67.9 % was respiratory syncytial virus. Forty-seven anamnestic, clinical, traditional laboratory and molecular genetic parameters were assessed as prognostic criteria. Determination of SNP genes of cytokines IL-4 (C-589T), IL-10 (G-1082A), IL-10 (C-592A), IL-10 (C-819T), TNF-α (G-308A), IL-17A (G197A), IL-17F (His161Arg), TLR2-753ArgGln, TLR6-Ser249Pro in venous blood was carried out by the polymerase chain reaction method.Results. An additional criterion for the risk of developing a severe course of bronchiolitis can be the mutant genotype (AA) SNP of the IL-10 gene (C-592A), which was detected exclusively in the group of patients with severe bronchiolitis, increasing the risk of developing a severe disease by 16.11 times (OR = 16.11; 95 % CI: 0.81–121.22, p = 0.02) in conjunction with already established modifying factors: the presence of congenital heart disease, bronchopulmonary dysplasia, prematurity, birth weight < 1500 g. Based on a comprehensive assessment of the established risk factors, a method has been developed that allows calculate the likelihood of developing a severe course of acute viral bronchiolitis. Conclusion. The use of the developed prediction method will not only increase the likelihood of developing severe acute viral bronchiolitis in children, but also determine the priority group among children with predictors of severe viral bronchiolitis for priority immunoprophylaxis against RS-virus infection.

Association of Congenital and Acquired Cardiovascular Conditions With COVID-19 Severity Among Pediatric Patients in the US

IMPORTANCE

Identifying the associations between severe COVID-19 and individual cardiovascular conditions in pediatric patients may inform treatment.

OBJECTIVE

To assess the association between previous or preexisting cardiovascular conditions and severity of COVID-19 in pediatric patients.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from a large, multicenter, electronic health records database in the US. The cohort included patients aged 2 months to 17 years with a laboratory-confirmed diagnosis of COVID-19 or a diagnosis code indicating infection or exposure to SARS-CoV-2 at 85 health systems between March 1, 2020, and January 31, 2021.

EXPOSURES

Diagnoses for 26 cardiovascular conditions between January 1, 2015, and December 31, 2019 (before infection with SARS-CoV-2).

MAIN OUTCOMES AND MEASURES

The main outcome was severe COVID-19, defined as need for supplemental oxygen or in-hospital death. Mixed-effects, random intercept logistic regression modeling assessed the significance and magnitude of associations between 26 cardiovascular conditions and COVID-19 severity. Multiple comparison adjustment was performed using the Benjamini-Hochberg false discovery rate procedure.

RESULTS

The study comprised 171 416 pediatric patients; the median age was 8 years (IQR, 2-14 years), and 50.28% were male. Of these patients, 17 065 (9.96%) had severe COVID-19. The random intercept model showed that the following cardiovascular conditions were associated with severe COVID-19: cardiac arrest (odds ratio [OR], 9.92; 95% CI, 6.93-14.20), cardiogenic shock (OR, 3.07; 95% CI, 1.90-4.96), heart surgery (OR, 3.04; 95% CI, 2.26-4.08), cardiopulmonary disease (OR, 1.91; 95% CI, 1.56-2.34), heart failure (OR, 1.82; 95% CI, 1.46-2.26), hypotension (OR, 1.57; 95% CI, 1.38-1.79), nontraumatic cerebral hemorrhage (OR, 1.54; 95% CI, 1.24-1.91), pericarditis (OR, 1.50; 95% CI, 1.17-1.94), simple biventricular defects (OR, 1.45; 95% CI, 1.29-1.62), venous embolism and thrombosis (OR, 1.39; 95% CI, 1.11-1.73), other hypertensive disorders (OR, 1.34; 95% CI, 1.09-1.63), complex biventricular defects (OR, 1.33; 95% CI, 1.14-1.54), and essential primary hypertension (OR, 1.22; 95% CI, 1.08-1.38). Furthermore, 194 of 258 patients (75.19%) with a history of cardiac arrest were younger than 12 years.

CONCLUSIONS AND RELEVANCE

The findings suggest that some previous or preexisting cardiovascular conditions are associated with increased severity of COVID-19 among pediatric patients in the US and that morbidity may be increased among individuals children younger than 12 years with previous cardiac arrest.

Examining the interseasonal resurgence of respiratory syncytial virus in Western Australia

BACKGROUND

Following a relative absence in winter 2020, a large resurgence of respiratory syncytial virus (RSV) detections occurred during the 2020/2021 summer in Western Australia. This seasonal shift was linked to SARS-CoV-2 public health measures. We examine the epidemiology and RSV testing of respiratory-coded admissions, and compare clinical phenotype of RSV-positive admissions between 2019 and 2020.

METHOD

At a single tertiary paediatric centre, International Classification of Diseases, 10th edition Australian Modification-coded respiratory admissions longer than 12 hours were combined with laboratory data from 1 January 2019 to 31 December 2020. Data were grouped into bronchiolitis, other acute lower respiratory infection (OALRI) and wheeze, to assess RSV testing practices. For RSV-positive admissions, demographics and clinical features were compared between 2019 and 2020.

RESULTS

RSV-positive admissions peaked in early summer 2020, following an absent winter season. Testing was higher in 2020: bronchiolitis, 94.8% vs 89.2% (p=0.01); OALRI, 88.6% vs 82.6% (p=0.02); and wheeze, 62.8% vs 25.5% (p<0.001). The 2020 peak month, December, contributed almost 75% of RSV-positive admissions, 2.5 times the 2019 peak. The median age in 2020 was twice that observed in 2019 (16.4 vs 8.1 months, p<0.001). The proportion of RSV-positive OALRI admissions was greater in 2020 (32.6% vs 24.9%, p=0.01). There were no clinically meaningful differences in length of stay or disease severity.

INTERPRETATION

The 2020 RSV season was in summer, with a larger than expected peak. There was an increase in RSV-positive non-bronchiolitis admissions, consistent with infection in older RSV-naïve children. This resurgence raises concern for regions experiencing longer and more stringent SARS-CoV-2 public health measures.

Risk Factors for Severe COVID-19 in Children: A Systematic Review and Meta-Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) has been the most important global issue since December 2019. Although the clinical course of COVID-19 is known to be milder in children than in adults, associated hospitalizations among children have increased since the emergence of contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and the achievement of a high vaccination rate in adults. Considering these global and domestic situations, we believe that risk stratification in children with COVID-19 is urgently needed for decision making regarding hospitalization priority in children infected with SARS-CoV-2 and vaccination priority against COVID-19.

METHODS

This systematic review and meta-analysis was performed by comprehensively searching the PubMed, EMBASE, Scopus and KoreaMed databases through August 25, 2021. The criteria for enrollment were "severe COVID-19" as poor outcomes (intensive care unit admission, invasive mechanical ventilation, and/or death) and underlying comorbidities before SARS-CoV-2 infection.

RESULTS

Among 872 screened studies, 17 articles were included in the systematic review, and 10 articles were included in the meta-analysis. Neonate (risk ratio [RR], 2.69; 95% confidence interval [CI], 1.83-3.97), prematurity in young infants (RR, 2.00; 95% CI, 1.63-2.46), obesity (RR, 1.43; 95% CI, 1.24-1.64), diabetes (RR, 2.26; 95% CI, 1.95-2.62), chronic lung disease (RR, 2.62; 95% CI, 1.71-4.00), heart disease (RR, 1.82; 95% CI, 1.58-2.09), neurologic disease (RR, 1.18; 95% CI, 1.05-1.33), and immunocompromised status (RR, 1.44; 95% CI, 1.01-2.04) were significant risk factors for severe COVID-19 in children. In the subgroup analysis, age younger than 3 months (RR, 0.26; 95% CI, 0.11-0.66), asthma (RR, 1.08; 95% CI, 0.98-1.20), and neurodevelopmental disorders (RR, 0.88; 95% CI, 0.75-1.04) were not risk factors for severe COVID-19.

CONCLUSION

Children with comorbidities such as obesity, diabetes, heart disease, chronic lung diseases other than asthma, seizure disorders, and an immunocompromised status had a high prevalence of severe COVID-19. Neonate and premature infants had a high risk of severe COVID-19. Defining the high-risk group for severe COVID-19 could help to guide hospital admission and priority for vaccination against SARS-CoV-2.

Reappraisal of the Subtropical Guidelines on Palivizumab Prophylaxis in Congenital Heart Disease

Objective: To define the impact of associated abnormalities on the efficacy of the novel subtropical guidelines for palivizumab prophylaxis on respiratory syncytial virus (RSV)-related hospitalizations in patients with hemodynamically significant congenital heart disease (hsCHD). Method: This prospective study enrolled every patient seen at a tertiary care center for hsCHD, who was born between 2014 and 2018 and received at least 1 dose of palivizumab, according to the subtropical guidelines. The patients were followed until the age of 2 years. Results: A total of 772 patients (49% male) were enrolled. Cyanotic CHD was seen in 46% of patients, of whom 23% had associated abnormalities. Lung/airway abnormalities (14%) were the most common followed by the genetic syndromes associated with CHD (7.3%). Among the 772 patients, RSV-related hospitalizations occurred in 3.2 and 2.2% children aged ≤ 12 and 13-24 months, respectively. Most of the RSV infections occurred in patients no longer satisfying the criteria for palivizumab prophylaxis. The patients with associated abnormalities but not the type of CHD, patient age, and patient sex were risk factors for RSV-related hospitalizations. The rates of RSV-related hospitalizations, admission to the intensive care unit, and endotracheal intubation were higher for patients with associated anomalies than for other patients before 24 months of age (10.2 vs. 4.0%, 67 vs. 33%, and 39 vs. 4.2%, p = 0.004, 0.06, 0.013, respectively). Conclusion: Children with abnormalities, especially genetic syndromes and lung/airway problems associated with CHD, are at high risk for RSV-related hospitalization. Our current subtropical guidelines for palivizumab prophylaxis in patients with hsCHD, should be revised to include the results of this study.

Burden of illness in infants and young children hospitalized for respiratory syncytial virus: A rapid review

Respiratory syncytial virus (RSV) infections are common among young children and represent a significant burden to patients, their families and the Canadian health system. Here we conduct a rapid review of the burden of RSV illness in children 24 months of age or younger. Four databases (Medline, Embase, Cochrane Database of Clinical Trials, ClinicalTrials.gov from 2014 to 2018), grey literature and reference lists were reviewed for studies on the following: children with or without a risk factor, without prophylaxis and with lab-confirmed RSV infection. Of 29 studies identified, 10 provided within-study comparisons and few examined clinical conditions besides prematurity. For infants of 33-36 weeks gestation (wGA) versus term infants, there was low-to-moderate certainty evidence for an increase in RSV-hospitalizations (n=599,535 infants; RR 2.05 [95% CI 1.89-2.22]; 1.3 more per 100 [1.1-1.5 more]) and hospital length of stay (n=7,597 infants; mean difference 1.00 day [95% CI 0.88-1.12]). There was low-to-moderate certainty evidence of little-to-no difference for infants born at 29-32 versus 33-36 wGA for hospitalization (n=12,812 infants; RR 1.20 [95% CI 0.92-1.56]). There was low certainty evidence of increased mechanical ventilation for hospitalized infants born at 29-32 versus 33-35 wGA (n=212 infants; RR 1.58, 95% CI 0.94-2.65). Among infants born at 32-35 wGA, hospitalization for RSV in infancy may be associated with increased wheeze and asthma-medication use across six-year follow-up (RR range 1.3-1.7). Children with versus without Down syndrome may have increased hospital length of stay (n=7,206 children; mean difference 3.00 days, 95% CI 1.95-4.05; low certainty). Evidence for other within-study comparisons was of very low certainty. In summary, prematurity is associated with greater risk for RSV-hospitalization and longer hospital length of stay, and Down syndrome may be associated with longer hospital stay for RSV. Respiratory syncytial virus-hospitalization in infancy may be associated with greater wheeze and asthma-medication use in early childhood. Lack of a comparison group was a major limitation for many studies.

The Burden of Respiratory Syncytial Virus in Children Under 2 Years of Age in a Rural Community in Maharashtra, India

BACKGROUND

Globally, respiratory syncytial virus (RSV) is a common cause of acute lower tract infection (LRTI) in children younger than 2 years of age, but there are scant population-based studies on the burden of RSV illness in rural communities and no community studies in preterm infants.

METHODS

Active surveillance of LRTI was performed in the community and hospital setting for the population of 93 tribal villages in Melghat, Central India, over 4 respiratory seasons. A nasopharyngeal swab was obtained from cases presenting as a severe LRTI for molecular analysis of respiratory pathogens including RSVA and B.

RESULTS

High rates of RSV-associated LRTI were found in preterm and term infants beyond 6 months of age, extending into the second year of life. Community severe RSV LRTI rates for 0-11 months of age was 22.4 (18.6-27.0)/1000 child-years (CY) and the hospital-associated rate was 14.1 (11.1-17.8)/1000 CY. For preterm infants, these rates were 26.2 (17.8-38.5)/1000 CY and 12.6 (7.2-22.0)/1000 CY. Comparable rates in the first 6 months were 15.9 (11.8-21.4)/1000 CY and 12.9 (9.3-18.0)/1000 CY in term infants and 26.3 (15.4-45.0)/1000 CY and 10.1 (4.2-24.2)/1000 CY for preterms. The single RSV B season had higher incidences of RSV LRTI in every age group than the 2 RSV A seasons in both preterm and term infants. There were 11 deaths, all term infants.

CONCLUSIONS

Studies restricted to the healthcare settings significantly underestimate the burden of RSV LRTI and preterm and term infants have comparable burdens of disease in this rural community.

A Comparison of Respiratory Syncytial Viral Prophylaxis in Multiple Births versus Singletons in the Canadian Registry of Palivizumab

OBJECTIVE

The aim of this study is to compare respiratory illness-related hospitalization (RIH) and respiratory syncytial virus (RSV)-related hospitalization (RSVH) in multiple births versus singletons, who received palivizumab during the RSV season and participated in the Canadian registry of palivizumab (CARESS).

STUDY DESIGN

Prospective, observational study of infants aged <2 years recruited across 32 centers over 12 RSV seasons from 2005 to 2017. Demographic data were collected at enrolment and RIH events were recorded monthly.

RESULTS

A total of 25,003 infants were enrolled of whom 6,949 (27.8%) were of multiple birth, and 18,054 (72.2%) were singletons. A significantly larger proportion of the multiple births were premature (80.2%) compared with the singleton group (56.8%). Multiples had a lower gestational age (mean ± standard deviation): 31.2 ± 3.2 versus 33.2 ± 5.5 weeks and birth weight (mean: 1,590 ± 606.8 vs. 2,069.4 ± 1068.5 g; both p < 0.0005). They were younger at enrolment (4.5 ± 5.0 vs. 6.1 ± 6.8 months), and fewer attended daycare (1.9 vs. 4.6%), and experienced exposure to smoking (24.5 vs. 29.9%), but more lived in a crowded household (36.7 vs. 19.4%); all p < 0.0005. Multiples had a longer length of neonatal stay (51.1 ± 65.9 vs. 47.9 ± 67.8 days), and more required respiratory support (65.7 vs. 57.7%), but for shorter duration (22.6 ± 32.9 vs. 24.7 ± 40.6 days); all p < 0.001. RIH and RSVH rates (%) in multiples versus singletons were 4.7; 7.7 and 1.4; and 1.6, respectively. Cox regression showed that multiples had a lower risk of RIH compared with singletons (hazard ratio [HR] = 0.616, 95% confidence interval [CI]: 0.543-0.698, p < 0.0005), but not RSVH (HR: 0.77, 95% CI: 0.57-1.02, p = 0.071).

CONCLUSION

Multiple birth infants, who are known to be at greater risk for severe RSVH compared with singletons, are well protected by palivizumab, provided adherence to the monthly injection scheme is guaranteed.

Prevalence and Risk Factors of Respiratory Syncytial Virus in Children under 5 Years of Age in the WHO European Region: A Systematic Review and Meta-Analysis

A respiratory syncytial virus (RSV) is the major cause of respiratory tract infection in children under 5 years. However, RSV infection in the European Region of the World Health Organization has not been systematically reviewed. The aim was to determine the prevalence and factors associated with RSV in children under 5 years of age in European regions. A systematic review and meta-analysis was performed. CINAHL, Medline, LILACS, ProQuest, SciELO, and Scopus databases were consulted for studies published in the last 5 years, following Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The search equation was "respiratory syncytial virus AND (newborn OR infant OR child) AND (prevalence OR risk factors)". Studies reporting the prevalence of RSV were eligible for inclusion in the meta-analysis. A total of 20 articles were included. The meta-analytic prevalence estimation of RSV, with a sample of n = 16,115 children, was 46% (95% CI 34-59%). The main risk factors were age, male gender, winter season, and environmental factors such as cold temperatures, higher relative humidity, high concentrations of benzene, exposure to tobacco, and living in urban areas. Robust age-specific estimates of RSV infection in healthy children should be promoted in order to determine the optimal age for immunization. In addition, it is necessary to analyse in greater depth the potentially predictive factors of RSV infection, to be included in prevention strategies.

Content validity of the nursing diagnostic Breathing Pattern, Ineffective, in children with congenital heart defects

OBJECTIVE

To estimate the content validity of the nursing diagnostic Breathing Pattern, Ineffective, in children with congenital heart defects.

METHOD

Methodological study in two stages: 1) integrative literature review; 2) content validation, with 23 nurses. An instrument with 10 related factors and 21 defining characteristics for data collection was used. The analysis by the evaluators was carried out using the relevance criteria. The Content Validity Index was used. Valid results were those above 0.9 with a Wilcoxon test above 0.05.

RESULTS

The final proposal incorporates nine from the ten causal factors. From them, five do not belong in the NANDA-I list. Regarding the defining characteristics, they were all considered to be relevant, and five are not among the list of signs and symptoms of the NANDA-I taxonomy.

CONCLUSION

The findings of this study include specific elements of the pediatric population with congenital heart defect which are not present in the structure of the diagnostic being studied.

Acute Lower Respiratory Infections Associated With Respiratory Syncytial Virus in Children With Underlying Congenital Heart Disease: Systematic Review and Meta-analysis

BACKGROUND

Respiratory syncytial virus (RSV) is the most common viral pathogen associated with acute lower respiratory infections (ALRIs), with significant childhood morbidity and mortality worldwide. Estimates reporting RSV-associated ALRI (RSV-ALRI) severity in children with congenital heart disease (CHD) are lacking, thus warranting the need to summarize the available data. We identified relevant studies to summarize the findings and conducted a meta-analysis of available data on RSV-associated ALRI hospitalizations in children aged <5 years, comparing those with underlying CHD to those without CHD.

METHODS

We conducted a systematic search of existing relevant literature and identified studies reporting hospitalization of children aged <5 years with RSV-ALRI with underlying or no CHD. We summarized the data and conducted (where possible) a random-effects meta-analysis to compare the 2 groups.

RESULTS

We included 18 studies that met our strict eligibility criteria. The risk of severe RSV-ALRI (odds ratio, 2.2; 95% confidence interval [CI], 1.6-2.8), the rate of hospitalization (incidence rate ratio, 2.8; 95% CI, 1.9-4.1), and the case-fatality ratio (risk ratio [RR], 16.5; 95% CI, 13.7-19.8) associated with RSV-ALRI was higher among children with underlying CHD as compared to those without no CHD. The risk of admission to the intensive care unit (RR, 3.9; 95% CI, 3.4-4.5), need for supplemental oxygen therapy (RR, 3.4; 95% CI, .5-21.1), and need for mechanical ventilation (RR, 4.1; 95% CI, 2.1-8.0) was also higher among children with underlying CHD.

CONCLUSION

This is the most detailed review to show more-severe RSV-ALRI among children aged <5 years with underlying CHD, especially hemodynamically significant underlying CHD, as compared those without CHD, supporting a need for improved RSV prophylactics and treatments that also have efficacy in children older than 1 year.

Current State of Respiratory Syncytial Virus Disease and Management

Respiratory syncytial virus (RSV) is a major cause of hospitalizations due to pneumonia and bronchiolitis. Substantial morbidity and socioeconomic burden are associated with RSV infection worldwide. Populations with higher susceptibility to developing severe RSV include premature infants, children with chronic lung disease of prematurity (CLDP) or congenital heart disease (CHD), elderly individuals aged > 65 years, and immunocompromised individuals. In the pediatric population, RSV can lead to long-term sequelae such as wheezing and asthma, which are associated with increased health care costs and reduced quality of life. Treatment for RSV is mainly supportive, and general preventive measures such as good hygiene and isolation are highly recommended. Although vaccine development for RSV has been a global priority, attempts to date have failed to yield a safe and effective product for clinical use. Currently, palivizumab is the only immunoprophylaxis (IP) available to prevent severe RSV in specific high-risk pediatric populations. Well-controlled, randomized clinical trials have established the efficacy of palivizumab in reducing RSV hospitalization (RSVH) in high-risk infants including moderate- to late-preterm infants. However, the American Academy of Pediatrics (AAP), in its 2014 policy, stopped recommending RSV IP use for ≥ 29 weeks' gestational age infants. Revisions to the AAP policy for RSV IP have largely narrowed the proportion of pediatric patients eligible to receive RSV IP and have been associated with an increase in RSVH and morbidity. On the other hand, after reviewing the recent evidence on RSV burden, the National Perinatal Association, in its 2018 clinical practice guidelines, recommended RSV IP use for a wider pediatric population. As the AAP recommendations drive insurance reimbursements for RSV IP, they should be revised to help further mitigate RSV disease burden.

Challenges in the prevention or treatment of RSV with emerging new agents in children from low- and middle-income countries

INTRODUCTION

Respiratory syncytial virus (RSV) causes approximately 120,000 deaths annually in children <5 years, with 99% of fatalities occurring in low- and middle-income countries (LMICs).

AREAS COVERED

There are numerous RSV interventions in development, including long-acting monoclonal antibodies, vaccines (maternal and child) and treatments which are expected to become available soon. We reviewed the key challenges and issues that need to be addressed to maximize the impact of these interventions in LMICs. The epidemiology of RSV in LMICs was reviewed (PubMed search to 30 June 2020 inclusive) and the need for more and better-quality data, encompassing hospital admissions, community contacts, and longer-term respiratory morbidity, emphasized. The requirement for an agreed clinical definition of RSV lower respiratory tract infection was proposed. The pros and cons of the new RSV interventions are reviewed from the perspective of LMICs.

EXPERT OPINION

We believe that a vaccine (or combination of vaccines, if practicable) is the only viable solution to the burden of RSV in LMICs. A coordinated program, analogous to that with polio, involving governments, non-governmental organizations, the World Health Organization, the manufacturers and the healthcare community is required to realize the full potential of vaccine(s) and end the devastation of RSV in LMICs.

Updated cost-effectiveness analysis of palivizumab (Synagis) for the prophylaxis of respiratory syncytial virus in infant populations in the UK

AIMS

Respiratory syncytial virus (RSV) is a common cause of respiratory infection in infants and severe infection can result in hospitalization. The passive immunization, palivizumab, is used as prophylaxis against RSV, however, use in the UK is restricted to populations at high risk of hospitalization. This study assesses the cost-effectiveness (CE) of palivizumab in premature infants with and without risk factors for hospitalization (congenital heart disease [CHD], bronchopulmonary dysplasia [BPD]).

METHODS

A decision tree model, based on earlier CE analyses, was updated using data derived from targeted literature reviews and advice gained from a Round Table meeting. All costs were updated to 2019 prices. One-way and probabilistic sensitivity analyses were performed to assess the degree of uncertainty surrounding the results.

RESULTS

Palivizumab is dominant (i.e. clinically superior and cost saving) when used in premature infants born ≤35 weeks gestational age (wGA) without CHD or BPD and aged <6 months at the start of the RSV season, infants aged <24 months with CHD and infants aged <24 months requiring treatment for BPD within the last 6 months.

LIMITATIONS

One-way sensitivity analysis suggests that these results are highly sensitive to the efficacy of prophylaxis, number of doses, impact of long-term respiratory sequalae, rate of hospitalization and mortality due to RSV. A conservative approach has been taken toward long-term respiratory sequalae due to uncertainty around epidemiology and etiology and a lack of recent cost and utility data.

CONCLUSIONS

Palivizumab prophylaxis is cost-effective in preventing severe RSV infection requiring hospital admission in a wider population than currently recommended in UK guidelines. Prophylaxis in premature infants born <29 wGA, 29-32 wGA and 33-35 wGA without CHD or BPD aged <6 months at the start of the RSV season is not funded under current guidance, however, prophylaxis has been demonstrated to be cost-effective in this analysis.

Cardiovascular impact of COVID-19 with a focus on children: A systematic review

BACKGROUND

Since the beginning of the pandemic, coronavirus disease-2019 (COVID-19) in children has shown milder cases and a better prognosis than adults. Although the respiratory tract is the primary target for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), cardiovascular involvement is emerging as one of the most significant and life-threatening complications of SARS-CoV-2 infection in adults.

AIM

To summarize the current knowledge about the potential cardiovascular involvement in pediatric COVID-19 in order to give a perspective on how to take care of them during the current pandemic emergency.

METHODS

Multiple searches in MEDLINE, PubMed were performed using the search terms "COVID-19" or "SARS-CoV-2" were used in combination with "myocardial injury" or "arrhythmia" or "cardiovascular involvement" or "heart disease" or "congenital heart disease" or "pulmonary hypertension" or "long QT" or "cardiomyopathies" or "channelopathies" or "Multisystem inflammatory system" or "PMIS" or "MIS-C" or "Pediatric multisystem inflammatory syndrome" or "myocarditis" or "thromboembolism to identify articles published in English language from January 1st, 2020 until July 31st, 2020. The websites of World Health Organization, Centers for Disease control and Prevention, and the Johns Hopkins Coronavirus Resource Center were reviewed to provide up to date numbers and infection control recommendations. Reference lists from the articles were reviewed to identify additional pertinent articles. Retrieved manuscripts concerning the subject were reviewed by the authors, and the data were extracted using a standardized collection tool. Data were subsequently analyzed with descriptive statistics. For Pediatric multisystemic inflammatory syndrome temporally associated with COVID-19 (PMIS), multiple meta-analyses were conducted to summarize the pooled mean proportion of different cardiovascular variables in this population in pseudo-cohorts of observed patients.

RESULTS

A total of 193 articles were included. Most publications used in this review were single case reports, small case series, and observational small-sized studies or literature reviews. The meta-analysis of 16 studies with size > 10 patients and with complete data about cardiovascular involvement in children with PMIS showed that PMIS affects mostly previously healthy school-aged children and adolescents presenting with Kawasaki disease-like features and multiple organ failure with a focus on the heart, accounting for most cases of pediatric COVID-19 mortality. They frequently presented cardiogenic shock (53%), ECG alterations (27%), myocardial dysfunction (52%), and coronary artery dilation (15%). Most cases required PICU admission (75%) and inotropic support (57%), with the rare need for extracorporeal membrane oxygenation (4%). Almost all of these children wholly recovered in a few days, although rare deaths have been reported (2%). Out of PMIS cases we identified 10 articles reporting sporadic cases of myocarditis, pulmonary hypertension and cardiac arrythmias in previously healthy children. We also found another 10 studies reporting patients with pre-existing heart diseases. Most cases consisted in children with severe COVID-19 infection with full recovery after intensive care support, but cases of death were also identified. The management of different cardiac conditions are provided based on current guidelines and expert panel recommendations.

CONCLUSION

There is still scarce data about the role of cardiovascular involvement in COVID-19 in children. Based on our review, children (previously healthy or with pre-existing heart disease) with acute COVID-19 requiring hospital admission should undergo a cardiac workup and close cardiovascular monitoring to identify and treat timely life-threatening cardiac complications.

Burden of respiratory syncytial virus hospitalisation among infants born at 32-35 weeks' gestational age in the Northern Hemisphere: pooled analysis of seven studies

To provide comprehensive information on the epidemiology and burden of respiratory syncytial virus hospitalisation (RSVH) in preterm infants, a pooled analysis was undertaken of seven multicentre, prospective, observational studies from across the Northern Hemisphere (2000–2014). Data from all 32⁰–35⁶ weeks' gestational age (wGA) infants without comorbidity were analysed. RSVH occurred in 534/14 504 (3.7%) infants; equating to a rate of 5.65 per 100 patient-seasons, with the rate in individual wGA groups dependent upon exposure time (P = 0.032). Most RSVHs (60.1%) occurred in December–January. Median age at RSVH was 88 days (interquartile range (IQR): 54–159). Respiratory support was required by 82.0% of infants: oxygen in 70.4% (median 4 (IQR: 2–6) days); non-invasive ventilation in 19.3% (median 3 (IQR: 2–5) days); and mechanical ventilation in 10.2% (median 5 (IQR: 3–7) days). Intensive care unit admission was required by 17.9% of infants (median 6 days (IQR: 2–8) days). Median overall hospital length of stay (LOS) was 5 (IQR: 3–8) days. Hospital resource use was similar across wGA groups except for overall LOS, which was shortest in those born 35 wGA (median 3 vs. 4–6 days for 32–34 wGA; P < 0.001). Strategies to reduce the burden of RSVH in otherwise healthy 32–35 wGA infants are indicated.

The Assessment of Myocardial Strain by Cardiac Imaging in Healthy Infants with Acute Bronchiolitis: A Systematic Review and Meta-Analysis

This study aims to systematically review the incidence of myocardial strain detected by echocardiography in previously healthy infants with acute bronchiolitis and its role as a predictor for adverse outcomes in this setting.

METHODS

Pubmed/Medline, Excerpta Medica Data Base (EMBASE), and Cochrane Library were searched in April 2020 to identify original observational prospective studies that systematically performed echocardiography for the screening of myocardial strain in healthy infants with acute bronchiolitis. Pooled estimates were generated using random-effects models. Heterogeneity within studies was assessed using Cochran's Q and I² statistics. Funnel plots and Egger´s regression method were constructed to evaluate publication bias. Sensitivity analyses were also conducted to evaluate potential sources of heterogeneity.

RESULTS

After a detailed screening of 305 articles, a total of 10 studies with 395 participants (mean of 40 participants per study) was included. Five of them were classified as high-quality studies. Up to 28% of cases presented adverse outcomes. The echocardiographic screening for myocardial strain was performed within the first 24 h of admission in 92% cases. Tissue Doppler imaging and Speckle-Tracking echocardiography were performed only in 20% of cases. The presence of pulmonary hypertension was evaluated with methods different from the tricuspid regurgitation jet in 64% of cases. Seven studies found some grade of myocardial strain with a pooled incidence of 21% (CI 95%, 11-31%), in the form of pulmonary hypertension (pooled incidence of 20% (CI 95%, 11-30%)), and myocardial dysfunction (pooled incidence of 5% (CI 95%, 1-9%)). The presence of these echocardiographic alterations was associated with adverse outcomes (pooled relative risk = 16; CI 95%, 8.2-31.5). After a subgroup analysis based on the echocardiographic techniques used, no significant heterogeneity across the studies was observed. There was no evidence of publication bias when assessed by Egger´s test. Cardiac biomarkers to assess myocardial strain were used in five studies. Only N-terminal-pro-brain natriuretic peptide accurately predicted the presence of myocardial strain by echocardiography.

CONCLUSIONS

Myocardial strain is not infrequent in previously healthy infants with acute bronchiolitis, and it could be present at the early stages of the disease with prognostic implications. There is a need for sufficiently powered prospective studies with a similar methodology, preferably employing advanced imaging techniques, to conclusively address the usefulness of the assessment of myocardial strain in this setting.

Risk factors for bronchiolitis hospitalization in infants: A French nationwide retrospective cohort study over four consecutive seasons (2009-2013)

Objectives

Large studies are needed to update risk factors of bronchiolitis hospitalization. We performed a nationwide analysis of hospitalization rates for bronchiolitis over four consecutive bronchiolitis seasons to identify underlying medical disorders at risk of bronchiolitis hospitalization and assess their frequency.

Methods

Data were retrieved from the French National Hospital Discharge database. Of all infants discharged alive from maternity wards from January 2008 to December 2013 in France (N = 3,884,791), we identified four consecutive cohorts at risk of bronchiolitis during the seasons of 2009–2010 to 2012–2013. The main outcome was bronchiolitis hospitalization during a season. Individual risk factors were collected.

Results

Among infants, 6.0% were preterm and 2.0% had ≥1 chronic condition including 0.2% bronchopulmonary dysplasia (BPD) and 0.2% hemodynamically significant congenital heart disease (HS-CHD). Bronchiolitis hospitalization rates varied between seasons (min: 1.26% in 2010–2011; max: 1.48% in 2012–2013; p<0.001). Except omphalocele, the following conditions were associated with an increased risk for bronchiolitis hospitalization: solid organ (9.052; 95% CI, 4.664–17.567) and stem cell transplants (6.012; 95% CI, 3.441–10.503), muscular dystrophy (4.002; 95% CI, 3.1095–5.152), cardiomyopathy (3.407; 95% CI, 2.613–4.442), HS-CHD (3.404; 95% CI, 3.153–3.675), congenital lung disease and/or bronchial abnormalities, Down syndrome, congenital tracheoesophageal fistula, diaphragmatic hernia, pulmonary hypertension, chromosomal abnormalities other than Down syndrome, hemodynamically non-significant CHD, congenital abnormalities of nervous system, cystic fibrosis, cleft palate, cardiovascular disease occurring during perinatal period, and BPD.

Conclusion

Besides prematurity, BPD, and HS–CHD, eighteen underlying conditions were associated with a significant increased risk for bronchiolitis hospitalization in a nationwide population.

Respiratory Syncytial Virus and Associations With Cardiovascular Disease in Adults

Respiratory syncytial virus (RSV) is historically known for causing respiratory illness in young children, but the appreciation of its impact on older adults is growing. Studies have shown that hospitalization for respiratory illness due to RSV is complicated by cardiovascular events in 14% to 22% of adult patients, including worsening congestive heart failure, acute coronary syndrome, and arrhythmias. Additionally, underlying cardiovascular disease is associated with hospitalization in 45% to 63% of adults with confirmed RSV. In summary, patients with cardiopulmonary disease have higher rates of health care utilization for RSV-related illness and worse outcomes. Patients with cardiovascular disease likely represent an important target population for the rapidly developing field of RSV vaccines.

NT-proBNP plasma levels as biomarkers for pulmonary hypertension in healthy infants with respiratory syncytial virus infection

Aim: To explore NT-proBNP as biomarker for pulmonary hypertension (PH) in infants with respiratory syncytial virus infection (RSVI). Patients & methods: We prospectively enrolled 93 healthy infants with RSVI aged 1-12 months. NT-proBNP determination and echocardiography were performed at admission. Results: PH was found in 22% of patients and associated with a severe course of the disease. NT-proBNP >1635 pg/ml resulted an independent predictor for PH (odds ratio: 16.46 [95% CI: 4.10-66; p < 0.001]). The diagnostic performance of NT-proBNP to detect PH in RSVI was high (area under receiver operator curve of 0.932 [95% CI: 0.883-0.981; p < 0.001]). Conclusions: The presence of PH in healthy infants with RSVI is associated with worse outcomes. NT-proBNP resulted an accurate biomarker for PH in this setting.

Burden of Respiratory Syncytial Virus Disease and Mortality Risk Factors in Argentina: 18 Years of Active Surveillance in a Children's Hospital

BACKGROUND

Respiratory syncytial virus is the leading cause of acute lower respiratory infection in children. We aimed to describe the clinical-epidemiologic pattern and risk factors for mortality associated with RSV infection.

METHODS

This is a prospective, cross-sectional study of acute lower respiratory infection in children admitted to the Children's Hospital during 2000 to 2017. Viral diagnosis was made by fluorescent antibody techniques or real-time-polymerase chain reaction. We compared clinical-epidemiologic characteristics of RSV infection in nonfatal versus fatal cases. Multiple logistic regression was used to identify independent predictors of mortality.

RESULTS

Of 15,451 patients with acute lower respiratory infection, 13,033 were tested for respiratory viruses and 5831 (45%) were positive: RSV 81.3% (4738), influenza 7.6% (440), parainfluenza 6.9% (402) and adenovirus 4.3% (251). RSV had a seasonal epidemic pattern coinciding with months of lowest average temperature. RSV cases show a case fatality rate of 1.7% (82/4687). Fatal cases had a higher proportion of prematurity (P < 0.01), perinatal respiratory history (P < 0.01), malnourishment (P < 0.01), congenital heart disease (P < 0.01), chronic neurologic disease (P < 0.01) and pneumonia at clinical presentation (P = 0.014). No significant difference between genders was observed. Most deaths occurred among children who had complications: respiratory distress (80.5%), nosocomial infections (45.7%), sepsis (31.7%) and atelectasis (13.4%). Independent predictors of RSV mortality were moderate-to-severe malnourishment, odds ratio (OR): 3.69 [95% confidence interval (CI): 1.98-6.87; P < 0.0001]; chronic neurologic disease, OR: 4.14 (95% CI: 2.12-8.08; P < 0.0001); congenital heart disease, OR: 4.18 (95% CI: 2.39-7.32; P< 0.0001); and the age less than 6 months, OR: 1.99 (95% CI: 1.24-3.18; P = 0.004).

CONCLUSIONS

RSV showed an epidemic pattern affecting mostly young children. Malnourishment, chronic neurologic disease, congenital heart disease and the age less than 6 months were the independent risk factors for RSV mortality.

Role of Type I Interferon (IFN) in the Respiratory Syncytial Virus (RSV) Immune Response and Disease Severity

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract disease in children <2 years of age. Increased morbidity and mortality have been reported in high-risk patients, such as premature infants, patients with cardiac disease, and severely immune compromised patients. Severe disease is associated with the virulence of the virus as well as host factors specifically including the innate immune response. The role of type I interferons (IFNs) in the response to RSV infection is important in regulating the rate of virus clearance and in directing the character of the immune response, which is normally associated with protection and less severe disease. Two RSV non-structural proteins, NS1 and NS2, as well as the envelope G glycoprotein are known to suppress type I IFN production and a robust type I IFN response to RSV does not occur in human infants or neonatal mouse models of RSV infection. Additionally, presence of type I IFNs are associated with mild symptoms in infants and administration of IFN-α prior to infection of neonatal mice with RSV reduces immunopathology. This evidence has driven RSV prophylaxis and therapeutic efforts to consider strategies for enhancing type I IFN production.

Hospitalization for Respiratory Syncytial Virus in Children with Down Syndrome Less than 2 Years of Age: A Systematic Review and Meta-Analysis

OBJECTIVES

To compare the respiratory syncytial virus (RSV)-related hospitalization rate, hospital length of stay (LOS), and need for assisted ventilation in children aged <2 years with Down syndrome and those without Down syndrome.

STUDY DESIGN

MEDLINE, Embase, and CINAHL databases were searched from inception up to December 2017. Studies that provided data on RSV-related hospitalization in children aged <2 years with Down syndrome and those without Down syndrome were included. Data were independently extracted in pairs by 2 reviewers and synthesized with random-effects meta-analysis.

RESULTS

In 10 studies including a total of 1 748 209 children, 12.6% of the children with Down syndrome (491 of 3882) were hospitalized with RSV infection. The presence of Down syndrome was associated with a significantly higher risk of RSV-related hospitalization (relative risk [RR], 6.06; 95% CI, 4.93-7.45; I² = 65%; Grading of Recommendations, Assessment, Development and Evaluation [GRADE], moderate). RSV-related LOS (mean difference, 2.11 days; 95% CI, 1.47-2.75 days; I² = 0%; GRADE, low), and the need for assisted ventilation (RR, 5.82; 95% CI, 1.81-18.69; I² = 84%; GRADE, low). Children with Down syndrome without congenital heart disease (RR, 6.31; 95% CI, 4.83-8.23; GRADE, moderate) also had a significantly higher risk of RSV-related hospitalization. The risk of RSV-related hospitalization remained significant in the subgroup of children aged <1 year (RR, 6.25; 95% CI, 4.71-8.28; GRADE, high).

CONCLUSION

RSV-related hospitalization, hospital LOS, and the need for assisted ventilation are significantly higher in children with Down syndrome aged <2 years compared with those without Down syndrome. The results should prompt reconsideration of the need for routine RSV prophylaxis in children with Down syndrome up to 2 years of age.

Respiratory syncytial virus prophylaxis in cystic fibrosis: the Canadian registry of palivizumab data (2005-2016)

Respiratory syncytial virus (RSV) may cause severe illness in cystic fibrosis (CF) children, but recommendations vary on prophylaxis. CARESS is a prospective registry of children who received palivizumab in 32 Canadian sites from 2005 to 2016. Demographic data were collected at enrollment and respiratory illness-related events recorded monthly. We reviewed respiratory illness hospitalization (RIH) and RSV hospitalization (RSVH) in CF children aged < 24 months versus those prophylaxed for standard indications (SI; prematurity, chronic lung disease [CLD] and congenital heart disease [CHD]), and complex medical disorders (CM). Of 23,228 children analyzed, 19,452 (83.8%) were SI, 3349 (14.4%) were CM, and 427 (1.8%) were CF. CF children were more likely to be Caucasian, heavier at birth and enrollment, and less likely to have a sibling or live in crowded conditions. CF children were similar to the other groups in daycare attendance, history of atopy, and exposure to smoking. RIH incidences were 4.3% (premature), 13.8% CLD, 11.5% CHD, 11.7% CM, and 6.8% CF. RSVH incidence in CF children was similar to that in the SI and CM groups: 1.1, 1.5, and 2.0% groups respectively. Cox regression analyses showed that compared to CF children, the HRs for RSVH in SI (HR 2.0 95% CI 0.5-8.3, p = 0.3) and CM (HR 2.4, 95% CI 0.6-9.8, p = 0.2) did not differ. CF children are equally at risk for RSVH relative to those prophylaxed for other indications. Pending robust evidence from prospective trials, palivizumab could perhaps be considered in the interim, for young CF patients born early during the RSV season with evidence of serious lung disease.

Palivizumab prophylaxis for respiratory syncytial virus in infants with cystic fibrosis: is there a need?

Respiratory syncytial virus (RSV) infection in cystic fibrosis (CF) infants is associated with significant morbidities. This study's objective is to evaluate the effectiveness and adverse events related to palivizumab (PVZ) in CF infants. Data on respiratory-related illness (RIH) and RSV hospitalizations (RSVH) were collected retrospectively in CF infants aged < 2 years in Alberta, Canada, from 2000 to 2017. Logistic regression models were used to compare the odds of RSVH or RIH in PVZ infants from the Canadian registry of palivizumab (CARESS) versus untreated (UPVZ) infants from Alberta, after adjusting for potential confounders. Illness severity was compared between cohorts using χ² and t tests. A total of 267 CF infants were included: 183 (PVZ) and 84 (UPVZ). A total of 53.3% were tested for RSV. Fifty-five infants experienced a RIH and 10 had a RSVH. The PVZ cohort experienced similar odds of RSVH but decreased odds of RIH versus UPVZ, adjusting for gestational age, birth weight, birth during RSV peak months, and presence of siblings (Exp(B) = 0.23 [0.11-0.49], p < 0.0005). In RSVH-related subjects, PVZ subjects experienced shorter length of overall stay (LOS; t = 2.39 [df = 7], p = 0.048). In those with a RIH, the PVZ group had shorter overall intensive care unit (t = 3.52 [df = 15], p = 0.003) and hospital LOS (t = 2.11 [df = 52], p = 0.04). No serious adverse events were related to PVZ. The odds of RSVH were similar between groups, but PVZ subjects had decreased odds of RIH. The low number of RSV tests performed may explain the similarity in RSVH rates. Significant differences in LOS may indicate decreased RSVH and RIH illness severity in the PVZ versus UPVZ groups.

Interferon lambda receptor 1 (IFNL1R) transcript is highly expressed in rhinovirus bronchiolitis and correlates with disease severity

BACKGROUND

As the expression of type III IFN receptor is restricted to the mucosal surfaces, its evaluation could be crucial to characterize the role of IFNλs during bronchiolitis.

OBJECTIVES

This study was designed to investigate airway type III IFN receptor (IFNLR1/IL10RB) expression during respiratory syncytial virus (RSV) or human rhinovirus (HRV) bronchiolitis.

STUDY DESIGN

Seventy-one 1-6 month old infants hospitalized with their first episode of acute RSV or HRV bronchiolitis were selected for this study. Expression of IFNLR1, IL10RB and IFN-stimulated genes (ISGs) MxA and ISG56 in cells of nasopharyngeal washings taken within the first 48 h of admission were determined by a real-time hydrolysis probe RT-PCR assay. The ability of types I and III IFNs to induce the expression of both IFNLR1 and IL10RB in vitro was also evaluated.

RESULTS

Airway IFNLR1 transcript levels were significantly higher in HRV bronchiolitis infants compared to those with RSV bronchiolitis. No differences were recorded for IL10RB-mRNA between RSV or HRV infection. IFNLR1 mRNA levels increased significantly in infants infected with the C species of HRV and in those with a higher clinical score index and with an eosinophil count >3%. There were no correlations in vivo between type III IFN receptors and those of ISGs and neither IFNLR1 nor IL10RB were induced in vitro by IFNs.

CONCLUSIONS

These results suggest that IFNLR1 are increased in HRV-infected infants with more severe bronchiolitis and blood eosinophilia and in those infected with the HRVC species.

Past, Present and Future Approaches to the Prevention and Treatment of Respiratory Syncytial Virus Infection in Children

INTRODUCTION

The REGAL (RSV Evidence - A Geographical Archive of the Literature) series has provided a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This seventh and final publication covers the past, present and future approaches to the prevention and treatment of RSV infection among infants and children.

METHODS

A systematic review was undertaken of publications between January 1, 1995 and December 31, 2017 across PubMed, Embase and The Cochrane Library. Studies reporting data on the effectiveness and tolerability of prophylactic and therapeutic agents for RSV infection were included. Study quality and strength of evidence (SOE) were graded using recognized criteria. A further nonsystematic search of the published literature and Clinicaltrials.gov on antiviral therapies and RSV vaccines currently in development was also undertaken.

RESULTS

The systematic review identified 1441 studies of which 161 were included. Management of RSV remains centered around prophylaxis with the monoclonal antibody palivizumab, which has proven effective in reducing RSV hospitalization (RSVH) in preterm infants < 36 weeks' gestational age (72% reduction), children with bronchopulmonary dysplasia (65% reduction), and infants with hemodynamically significant congenital heart disease (53% reduction) (high SOE). Palivizumab has also shown to be effective in reducing recurrent wheezing following RSVH (high SOE). Treatment of RSV with ribavirin has conflicting success (moderate SOE). Antibodies with increased potency and extended half-life are currently entering phase 3 trials. There are approximately 15 RSV vaccines in clinical development targeting the infant directly or indirectly via the mother.

CONCLUSION

Palivizumab remains the only product licensed for RSV prophylaxis, and only available for high-risk infants. For the general population, there are several promising vaccines and monoclonal antibodies in various stages of clinical development, with the aim to significantly reduce the global healthcare impact of this common viral infection.

FUNDING

AbbVie.

Effects of cannabinoid receptor type 2 in respiratory syncytial virus infection in human subjects and mice

An accumulating body of evidence suggests that the endocannabinoid system plays a significant role in pathophysiological processes and impacts disease severity. Here we investigate the possible role of a cannabinoid receptor type 2 (CB2) functional variant in determining disease severity and the potential pharmacological therapeutic effects of CB2 activation in viral respiratory infection. The common missense variant (CAA/CGG; Q63R) of the gene-encoding CB2 receptor (CNR2) was evaluated in 90 inpatient and 90 outpatient children with acute respiratory tract infection (ARTI). The frequency distribution of respiratory syncytial virus (RSV)-the main cause of severe cases of bronchiolitis and pneumonia in children-was studied in all collected samples. The mechanism through which CB2 affects clinical outcomes in case of RSV infection was studied in Balb/c mice model using AM630 as a CB2 antagonist. The potential therapeutic effect of CB2 activation during RSV infection was studied using a selective agonist, JWH133. The CB2 Q63R variation was associated with increased risk of hospitalization in children with ARTI. Children carrying the QQ genotype were more prone to developing severe ARTI (OR = 3.275, 95% CI: 1.221–8.705; p = 0.019). Of all the children enrolled in the study, 83 patients (46.1%) were found positive for RSV infection. The associated risk of developing severe ARTI following RSV infection increased more than two-fold in children carrying the Q allele (OR = 2.148, 95% CI: 1.092–4.224; p = 0.026). In mice, the blockade of CB2 by AM630 during RSV infection enhanced the influx of BAL cells and production of cytokines/chemokines while exaggerating lung pathology. CB2 activation by JWH133 reduces the influx of BAL cells and production of cytokines/chemokines while alleviating lung pathology. Collectively, CB2 is associated with RSV severity during infancy and may serve as a therapeutic target in RSV infection through the alleviation of virus-associated immunopathology.

The respiratory system in pediatric chronic heart disease

Cardiovascular disease in the pediatric population closely affects the respiratory system inducing water retention in the lungs and pulmonary edema, airway compression by cardiovascular structures, restrictive pulmonary physiology as a result of hemodynamic changes and surgical repair, susceptibility to respiratory infections, development of pulmonary hypertension, thrombosis, or hemorrhage. Chronic heart failure and congenital heart disease are characterized by various respiratory manifestations and symptoms mimicking lung disease, which are frequently difficult to diagnose and treat. Pulmonary function is multiply affected in pediatric heart disease with mostly restrictive but also obstructive and diffusion abnormalities. Patients with Fontan circulation represent a separate group with slow, passive pulmonary blood flow and distinct pathophysiology with low cardiac output heart failure, restrictive lung pattern, increased thromboembolic complications and rare conditions such as protein losing enteropathy and plastic bronchitis. Distinguishing between cardiovascular and pulmonary symptoms may be challenging in the growing population of pediatric and adult survivors of congenital heart disease and understanding of the relationship of the two systems in heart disease is crucial for the optimal management of these patients.

Defining the Incidence and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Children with Chronic Diseases

INTRODUCTION

REGAL (RSV Evidence-a Geographical Archive of the Literature) has provided a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This review covers the risk and burden of RSV infection in children with underlying medical conditions or chronic diseases (excluding prematurity and congenital heart disease).

METHODS

A systematic review of publications between January 1, 1995 and December 31, 2015 across PubMed, Embase, The Cochrane Library, and Clinicaltrials.gov was supplemented by papers identified by the authors through March 2017. Studies reporting data for hospital visits/admissions for RSV infection as well as studies reporting RSV-associated morbidity and mortality were included. Study quality and strength of evidence (SOE) were graded.

RESULTS

A total of 2703 studies were identified and 58 were included. Down syndrome, irrespective of prematurity and congenital heart disease (moderate SOE), immunocompromised children (low SOE), cystic fibrosis (low SOE), and neurologic conditions (low SOE) were associated with a significantly increased risk of RSV hospitalization. A number of other congenital malformations and chronic conditions were also associated with severe RSV disease (low SOE). In general, pre-existing disease was also a predisposing factor for RSV-related mortality (low SOE).

CONCLUSION

Severe RSV infection in infants and young children with underlying medical conditions or chronic diseases poses a significant health burden. Further studies are needed to fully quantify the epidemiology, burden and outcomes in these populations, in particular RSV-attributable mortality.

The Burden and Long-term Respiratory Morbidity Associated with Respiratory Syncytial Virus Infection in Early Childhood

INTRODUCTION

The REGAL (RSV Evidence-a Geographical Archive of the Literature) series provide a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. The objective of this fifth publication was to determine the long-term respiratory morbidity associated with RSV lower respiratory tract infection (RSV LRTI) in early life.

METHODS

A systematic review was undertaken for articles published between January 1, 1995 and December 31, 2015. This was supplemented by inclusion of papers published whilst drafting the manuscript. Studies reporting data on the incidence and long-term wheezing and asthma following RSV LRTI in early life were included. Study quality and strength of evidence (SOE) were graded using recognized criteria.

RESULTS

A total of 2337 studies were identified of which 74 were included. Prospective, epidemiologic studies consistently demonstrated that RSV LRTI is a significant risk factor for on-going respiratory morbidity characterized by transient early wheezing and recurrent wheezing and asthma within the first decade of life and possibly into adolescence and adulthood (high SOE). RSV LRTI was also associated with impaired lung function in these children (high SOE). Respiratory morbidity has been shown to result in reduced quality of life and increased healthcare resource use (moderate SOE). The mechanisms through which RSV contributes to wheezing/asthma development are not fully understood, but appear to relate to the viral injury, preexisting abnormal lung function and/or other factors that predispose to wheezing/asthma, including genetic susceptibility, altered immunology, eosinophilia, and associated risk factors such as exposure to environmental tobacco smoke (high SOE).

CONCLUSION

There is growing evidence that RSV LRTI in early childhood is associated with long-term wheezing and asthma and impaired lung function. Future research should aim to fully elucidate the pathophysiological mechanisms through which RSV causes recurrent wheezing/asthma.