Burden of Respiratory Syncytial Virus Infection During the First Year of Life

Risk Analysis of Respiratory Syncytial Virus Among Infants in the United States by Birth Month

BACKGROUND

Respiratory syncytial virus (RSV) is a major cause of morbidity and mortality among US infants. A child's calendar birth month determines their age at first exposure(s) to RSV. We estimated birth month-specific risk of medically attended (MA) RSV lower respiratory tract infection (LRTI) among infants during their first RSV season and first year of life (FYOL).

METHODS

We analyzed infants born in the USA between July 2016 and February 2020 using three insurance claims databases (two commercial, one Medicaid). We classified infants' first MA RSV LRTI episode by the highest level of care incurred (outpatient, emergency department, or inpatient), employing specific and sensitive diagnostic coding algorithms to define index RSV diagnoses. In our main analysis, we focused on infants' first RSV season. In our secondary analysis, we compared the risk of MA RSV LRTI during infants' first RSV season to that of their FYOL.

RESULTS

Infants born from May through September generally had the highest risk of first-season MA RSV LRTI-approximately 6-10% under the specific RSV index diagnosis definition and 16-26% under the sensitive. Infants born between October and December had the highest risk of RSV-related hospitalization during their first season. The proportion of MA RSV LRTI events classified as inpatient ranged from 9% to 54% (specific) and 5% to 33% (sensitive) across birth month and comorbidity group. Through the FYOL, the overall risk of MA RSV LRTI is comparable across birth months within each claims database (6-11% under the specific definition, 17-30% under the sensitive), with additional cases progressing to care at outpatient or ED settings.

CONCLUSIONS

Our data support recent national recommendations for the use of nirsevimab in the USA. For infants born at the tail end of an RSV season who do not receive nirsevimab, a dose administered prior to the onset of their second RSV season could reduce the incidence of outpatient- and ED-related events.

Pre-COVID-19-pandemic RSV epidemiology and clinical burden in pediatric primary care in Italy: a comparative analysis across two regions for the 2019/2020 season

BACKGROUND

Respiratory syncytial virus (RSV) infection in children under 5 years have a significant clinical burden, also in primary care settings. This study investigates the epidemiology and burden of RSV in Italian children during the 2019/20 pre-pandemic winter season.

METHODS

A prospective cohort study was conducted in two Italian regions. Children with Acute Respiratory Infection (ARI) visiting pediatricians were eligible. Nasopharyngeal swabs were collected and analyzed via multiplex PCR for RSV detection. A follow-up questionnaire after 14 days assessed disease burden, encompassing healthcare utilization and illness duration. Statistical analyses, including regression models, explored associations between variables such as RSV subtype and regional variations.

RESULTS

Of 293 children with ARI, 41% (119) tested positive for RSV. Median illness duration for RSV-positive cases was 7 days; 6% required hospitalization (median stay: 7 days). Medication was prescribed to 95% (110/116) of RSV cases, with 31% (34/116) receiving antibiotics. RSV subtype B and regional factors predicted increased healthcare utilization. Children with shortness of breath experienced a 36% longer illness duration.

CONCLUSIONS

This study highlights a significant clinical burden and healthcare utilization associated with RSV in pre-pandemic Italian primary care settings. Identified predictors, including RSV subtype and symptomatology, indicate the need for targeted interventions and resource allocation strategies. RSV epidemiology can guide public health strategies for the implementation of preventive measures.

Outpatient respiratory syncytial virus infections and novel preventive interventions

PURPOSE OF REVIEW

With interventions to prevent respiratory syncytial virus (RSV) infection within reach, this review aims to provide healthcare professionals with the latest information necessary to inform parents and assess the potential impact of RSV prevention on everyday practice. We address frequently asked questions for parental counseling.

RECENT FINDINGS

Numerous studies emphasize the major burden of RSV on young children, parents, healthcare and society. In the first year of life, about 14% of healthy term infants visit a doctor and 2% require hospitalization due to RSV. In older children (1--5 years), RSV infections and associated morbidity (wheeze, acute otitis media) are major drivers of outpatient visits. A novel maternal RSV vaccine and long-acting mAb can provide protection during infants' first months of life. This maternal vaccine showed 70.9% efficacy against severe RSV infection within 150 days after birth; the mAb nirsevimab reduces medically attended RSV infections by 79.5% within 150 days after administration. Both gained regulatory approval in the USA (FDA) and Europe (EMA).

SUMMARY

Novel RSV immunizations hold promise to reduce the RSV burden in infants, with substantial impact on everyday practice. Tailored parental guidance will be instrumental for successful implementation. Awaiting pediatric vaccines, RSV infections beyond infancy will still pose a significant outpatient burden.

Respiratory Syncytial Virus-Associated Hospitalizations in Children: A 10-Year Population-Based Analysis in Finland, 2008-2018

BACKGROUND

The risk of respiratory syncytial virus (RSV) hospitalization is highest during the first months of life, but few studies have assessed the population-based rates of hospitalization in monthly age groups of infants.

METHODS

We determined the average population-based rates of hospitalization with virologically confirmed RSV infections in children ≤15 years of age admitted during the 10-year period of 2008-2018. Testing for RSV was routine in all children hospitalized with respiratory infections, and all RSV-positive children admitted at any time during the study period were included in the analyses.

RESULTS

The annual population-based rate of RSV hospitalization was highest in infants 1 month of age (52.0 per 1000 children; 95% CI, 45.2-59.7), followed by infants <1 month of age (34.8 per 1000; 95% CI, 29.2-41.1) and those 2 months of age (32.2 per 1000; 95% CI, 26.9-38.4). In cumulative age groups, the rate of hospitalization was 39.7 per 1000 (95% CI, 36.2-43.4) among infants <3 months of age, 26.8 per 1000 (95% CI, 24.8-29.0) in infants aged <6 months, and 15.8 per 1000 (95% CI, 14.7-17.0) in those <12 months of age.

CONCLUSION

In monthly age groups of infants, the incidence rates of virologically confirmed RSV hospitalization in all infants up to 3 months of age were substantially higher than those reported in earlier studies. These data may be important for improving the estimates of the cost-effectiveness of various interventions to reduce the burden of RSV in young infants.

Effectiveness of Vaccines and Monoclonal Antibodies Against Respiratory Syncytial Virus: Generic Protocol for Register-Based Cohort Study

Several immunization products are currently being developed against respiratory syncytial virus (RSV) for children, pregnant females, and older adults, and some products have already received authorization. Therefore, studies to monitor the effectiveness of these products are needed in the following years. To assist researchers to conduct postmarketing studies, we developed a generic protocol for register-based cohort studies to evaluate immunization product effectiveness against RSV-specific and nonspecific outcomes. To conduct a study on the basis of this generic protocol, the researchers can use any relevant databases or healthcare registers that are available at the study site.

Panel 1: Epidemiology and global health, including child development, sequelae and complications

OBJECTIVE

To summarise the published research evidence on the epidemiology of otitis media, including the risk factors and sequelae associated with this condition.

DATA SOURCES

Medline (PubMed), Embase, and the Cochrane Library covering the period from 2019 to June 1st, 2023.

REVIEW METHODS

We conducted a broad search strategy using otitis [Medical Subject Heading] combined with text words to identify relevant articles on the prevalence, incidence, risk factors, complications, and sequelae for acute otitis media, otitis media with effusion, and chronic suppurative otitis media. At least one review author independently screened titles and abstracts of the retrieved records for each condition to determine whether the research study was eligible for inclusion. Any discrepancies were resolved by reviewing the full text followed by discussion with a second review author. Studies with more than 100 participants were prioritised.

RESULTS

Over 2,000 papers on otitis media (OM) have been published since 2019. Our review has highlighted around 100 of these publications. While the amount of otitis media research on the Medline database published each year has not increased, there has been an increase in epidemiological studies using routinely collected data and systematic review methodology. Most of the large incidence studies have addressed acute otitis media (AOM) in children. Several studies have described a decrease in incidence of AOM after the introduction of conjugate PCV vaccines. Similarly, a decrease was noted when rates of coronavirus disease of 2019 (COVID-19) were high and there were major public health efforts to reduce the spread of infection. There have been new studies on OM in adults and OM prevalence in a broader range of countries and population subgroups.

CONCLUSION

Overall, the rates of severe and/or suppurative OM appeared to be decreasing. However, there is substantial heterogeneity between populations. While better use of available data is informative, it can be difficult to predict rates of severe disease without accurate examination findings. Most memorably, the COVID-19 pandemic had an enormous impact on the research and clinical services for otitis media for most of the period under review.

IMPLICATIONS FOR PRACTICE

The use of routinely collected data for epidemiological studies will lead to greater variability in the definitions and diagnostic criteria used. The impact of new vaccines will continue to be important. Some of the lessons learned during the COVID-19 pandemic concerning behaviours that reduce spread of respiratory viruses can hopefully be used to decrease the burden of otitis media in the future. There are still many countries in the world where the burden of otitis media is not well described. In countries where otitis media has been studied over many years, new potential risk factors continue to be identified. In addition, a better understanding of the disease in specific subgroups has been achieved.

Substantial Burden of Nonmedically Attended RSV Infection in Healthy-Term Infants: An International Prospective Birth Cohort Study

BACKGROUND

During the first year of life, 1 in 4 infants develops a symptomatic respiratory syncytial virus (RSV) infection, yet only half seek medical attention. The current focus on medically attended RSV therefore underrepresents the true societal burden of RSV. We assessed the burden of nonmedically attended RSV infections and compared with medically attended RSV.

METHODS

We performed active RSV surveillance until the age of 1 year in a cohort (n = 993) nested within the Respiratory Syncytial Virus Consortium in EUrope (RESCEU) prospective birth cohort study enrolling healthy term-born infants in 5 European countries. Symptoms, medication use, wheezing, and impact on family life were analyzed.

RESULTS

For 97 of 120 (80.1%) nonmedically attended RSV episodes, sufficient data were available for analysis. In 50.5% (49/97), symptoms lasted ≥15 days. Parents reported impairment in usual daily activities in 59.8% (58/97) of episodes; worries, 75.3% (73/97); anxiety, 34.0% (33/97); and work absenteeism, 10.8% (10/93). Compared with medically attended RSV (n = 102, 9 hospital admissions), Respiratory Syncytial Virus NETwork (ReSViNET) severity scores were lower (3.5 vs 4.6, P < .001), whereas duration of respiratory symptoms and was comparable.

CONCLUSIONS

Even when medical attendance is not required, RSV infection poses a substantial burden to infants, families, and society. These findings are important for policy makers when considering the implementation of RSV immunization. Clinical Trials Registration. ClinicalTrials.gov (NCT03627572).

Inpatient Rsv-Management 2016-2022: Epidemiology and Adherence to A Bronchiolitis Treatment Standard at a German University Children's Hospital

BACKGROUND

This study analyzes the RSV season 2021/2022 in a referral children's hospital, compares the epidemiology and illness severity with RSV-infected inpatients from 2016 to 2020 and audits the adherence to our internal therapy standard for RSV bronchiolitis.

MATERIAL AND METHODS

Inpatients with rtPCR-confirmed RSV infection (Jan. 2016 to Jan. 2022).

RESULTS

The audit comprises 306 RSV inpatients, on average 50 hospitalizations per year; in 03/2020, a rapid RSV Season-Offset was observed. In the winter season 2020/2021, no patient with RSV was hospitalized. Beginning in July, we noticed a rapid increase of RSV-admissions (most cases in Sept./Oct, duration until Dec. 2021; n=53). In 2021-2022, a significant larger share needed PICU admission (9.4% vs 3.2%, p=0.040). Adherence to the internal guidance was low; only 11.8% (n=36) of all patients received supportive treatment without inhalative or systemic medications, 37% of all patients received antibiotics.

CONCLUSIONS

This audit confirms the strong impact of public preventive measures directed against SARS-CoV-2 transmission on RSV epidemiology. Few weeks after easing public COVID-19 restrictions (summer 2021), RSV inpatient cases rapidly increased, lasting until Dec. 2021. The audit of bronchiolitis management revealed surprisingly low adherence to the internal guidance, despite a face-to-face educational session with the attending pediatricians in Oct. 2021. Low adherence resulted in an unnecessary exposure of RSV patients to systemic medications of questionable benefit including antibiotics.

Characterisation of RSV infections in children without chronic diseases aged 0-36 months during the post-COVID-19 winter season 2022/2023

Background

Respiratory syncytial virus (RSV) is one of the leading causes of hospitalisation, morbidity, and mortality due to respiratory infection in the first years of life. This longitudinal prospective study outlines the 2022/23 season's viral patterns in Austria after the epidemiological changes determined by public health measures. We aimed to highlight differences within the RSV subtypes and genotypes in 0-36-month-old children without chronic diseases in the outpatient setting.

Methods

From November 2022 to March 2023 children younger than 36 months admitted to Vienna's largest paediatric primary healthcare centre with an acute respiratory infection were enrolled in this study. Nasal swabs and multiplex PCR panels detected 20 viruses including RSV subtypes and genotypes. Clinical presentation, features, and treatment of the participants were documented and analysed using the Modified Tal Score (MTS). Patients were scheduled for a telemedical follow-up one week after the initial appointment. Analysis was done using descriptive statistics, including Cramér V and binominal logarithmic regression.

Results

Among the 345 samples from 329 children, RSV was the most common virus (31.9%), followed by influenza (17.5%) and rhinovirus infections (20.58%). Of the RSV positive samples, only 13 cases were RSV subtype A (11.8%), whereas 97 were of subtype B (87.3%); ON1 and BA9 were the only detectable RSV genotypes (ON1: BA9 = 1:9.25). RSV was the main predictor of hospitalisation (OR: 7.5, 95% CI: (1.46-38.40), and age had a significant but smaller effect (OR: 0.89, 95% CI: (0.81-0.99). Almost all patients' clinical status improved within the first days.

Conclusion

RSV cases showed a rapid onset in late November 2022, and subtype B was predominant throughout the season. RSV infection was associated with higher hospitalisation rates, even after excluding high-risk patients (preterm and severe chronic diseases population).Further testing in the upcoming winter seasons will improve our knowledge of the dominant subtype and its association with disease severity, especially with the development of novel RSV vaccine candidates.

ISOM 2023 research Panel 4 - Diagnostics and microbiology of otitis media

OBJECTIVES

To identify and review key research advances from the literature published between 2019 and 2023 on the diagnosis and microbiology of otitis media (OM) including acute otitis media (AOM), recurrent AOM (rAOM), otitis media with effusion (OME), chronic suppurative otitis media (CSOM) and AOM complications (mastoiditis).

DATA SOURCES

PubMed database of the National Library of Medicine.

REVIEW METHODS

All relevant original articles published in Medline in English between July 2019 and February 2023 were identified. Studies that were reviews, case studies, relating to OM complications (other than mastoiditis), and studies focusing on guideline adherence, and consensus statements were excluded. Members of the panel drafted the report based on these search results.

MAIN FINDINGS

For the diagnosis section, 2294 unique records screened, 55 were eligible for inclusion. For the microbiology section 705 unique records were screened and 137 articles were eligible for inclusion. The main themes that arose in OM diagnosis were the need to incorporate multiple modalities including video-otoscopy, tympanometry, telemedicine and artificial intelligence for accurate diagnoses in all diagnostic settings. Further to this, was the use of new, cheap, readily available tools which may improve access in rural and lowmiddle income (LMIC) settings. For OM aetiology, PCR remains the most sensitive method for detecting middle ear pathogens with microbiome analysis still largely restricted to research use. The global pandemic response reduced rates of OM in children, but post-pandemic shifts should be monitored.

IMPLICATION FOR PRACTICE AND FUTURE RESEARCH

Cheap, easy to use multi-technique assessments combined with artificial intelligence and/or telemedicine should be integrated into future practice to improve diagnosis and treatment pathways in OM diagnosis. Longitudinal studies investigating the in-vivo process of OM development, timings and in-depth interactions between the triad of bacteria, viruses and the host immune response are still required. Standardized methods of collection and analysis for microbiome studies to enable inter-study comparisons are required. There is a need to target underlying biofilms if going to effectively prevent rAOM and OME and possibly enhance ventilation tube retention.

The disease burden of respiratory syncytial virus in Infants

PURPOSE OF REVIEW

To describe the current global burden of respiratory syncytial virus (RSV) in infants and its implications for morbidity, health resources and economic costs.

RECENT FINDINGS

New prophylactic therapies are on the horizon for RSV in the form of long-acting monoclonal antibodies suitable for healthy infants and maternal immunizations.

SUMMARY

Despite being responsible for significant global infant morbidity and mortality, until recently there have been no effective therapeutics available for healthy infants to protect them from RSV. Several new drugs are likely to be available within the next few years which could help relieve a huge burden on healthcare systems over the coming winters.

The Path Towards Effective Respiratory Syncytial Virus Immunization Policies: Recommended Actions

The respiratory syncytial virus (RSV) causes a substantial burden worldwide. After over six decades of research, there is finally a licensed immunization option that can protect the broad infant population, and other will follow soon. RSV immunization should be in place from season 2023/2024 onwards. Doing so requires thoughtful but swift steps. This paper reflects the view of four immunization experts on the efforts being made across the globe to accommodate the new immunization options and provides recommendations organized around five priorities: (I) documenting the burden of RSV in specific populations; (II) expanding RSV diagnostic capacity in clinical practice; (III) strengthening RSV surveillance; (IV) planning for the new preventive options; (V) achieving immunization targets. Overall, Spain has been a notable example of converting RSV prevention into a national desideratum and has pioneered the inclusion of RSV in some of the regional immunization calendars for infants facing their first RSV season.

Economic burden and health-related quality-of-life among infants with respiratory syncytial virus infection: A multi-country prospective cohort study in Europe

BACKGROUND

Respiratory syncytial virus (RSV) causes a considerable disease burden in young children globally, but reliable estimates of RSV-related costs and health-related quality-of-life (HRQoL) are scarce. This study aimed to evaluate the RSV-associated costs and HRQoL effects in infants and their caregivers in four European countries.

METHODS

Healthy term-born infants were recruited at birth and actively followed up in four European countries. Symptomatic infants were systematically tested for RSV. Caregivers recorded the daily HRQoL of their child and themselves, measured by a modified EQ-5D with Visual Analogue Scale, for 14 consecutive days or until symptoms resolved. At the end of each RSV episode, caregivers reported healthcare resource use and work absenteeism. Direct medical costs per RSV episode were estimated from a healthcare payer's perspective and indirect costs were estimated from a societal perspective. Means and 95% confidence intervals (CI) of direct medical costs, total costs (direct costs + productivity loss) and quality-adjusted life-day (QALD) loss per RSV episode were estimated per RSV episode, as well as per subgroup (medical attendance, country).

RESULTS

Our cohort of 1041 infants experienced 265 RSV episodes with a mean symptom duration of 12.5 days. The mean (95% CI) cost per RSV episode was €399.5 (242.3, 584.2) and €494.3 (317.7, 696.1) from the healthcare payer's and societal perspective, respectively. The mean QALD loss per RSV episode of 1.9 (1.7, 2.1) was independent of medical attendance (in contrast to costs, which also differed by country). Caregiver and infant HRQoL evolved similarly.

CONCLUSION

This study fills essential gaps for future economic evaluations by prospectively estimating direct and indirect costs and HRQoL effects on healthy term infants and caregivers separately, for both medically attended (MA) and non-MA laboratory-confirmed RSV episodes. We generally observed greater HRQoL losses than in previous studies which used non-community and/or non-prospective designs.

Efficacy of nirsevimab against respiratory syncytial virus lower respiratory tract infections in preterm and term infants, and pharmacokinetic extrapolation to infants with congenital heart disease and chronic lung disease: a pooled analysis of randomised controlled trials

BACKGROUND

In a phase 2b trial and the phase 3 MELODY trial, nirsevimab, an extended half-life, monoclonal antibody against respiratory syncytial virus (RSV), protected healthy infants born preterm or at full term against medically attended RSV lower respiratory tract infection (LRTI). In the MEDLEY phase 2-3 trial in infants at higher risk for severe RSV infection, nirsevimab showed a similar safety profile to that of palivizumab. The aim of the current analysis was to assess the efficacy of nirsevimab using a weight-banded dosing regimen in infants born between 29 weeks gestational age and full term.

METHODS

Infants enrolled in the phase 2b and MELODY trials were randomised (2:1) to receive a single intramuscular injection of nirsevimab (infants weighing <5 kg received 50 mg; those weighing ≥5 kg received 100 mg) or placebo before the RSV season. Infants in MEDLEY were randomised (2:1) to receive one dose of nirsevimab (infants weighing <5 kg received 50 mg; those weighing ≥5 kg received 100 mg) followed by four monthly placebo doses, or five once-a-month intramuscular doses of palivizumab. We report a prespecified pooled efficacy analysis assessing the weight-banded dosing regimen proposed on the basis of the phase 2b and MELODY trials, in addition to extrapolated efficacy in infants with chronic lung disease, congenital heart disease, or extreme preterm birth (<29 weeks' gestational age) based on pharmacokinetic data from the phase 2-3 MEDLEY safety trial. For the pooled efficacy analysis, the primary endpoint was incidence of medically attended RSV LRTI through 150 days post-dose. The secondary efficacy endpoint was number of admissions to hospital for medically attended RSV LRTI. The incidence of very severe RSV LRTI was an exploratory endpoint, defined as cases of hospital admission for medically attended RSV LRTI that required supplemental oxygen or intravenous fluids. We also did a prespecified exploratory analysis of medically attended LRTI of any cause (in the investigator's judgement) and hospital admission for respiratory illness of any cause (defined as any upper respiratory tract infection or LRTI leading to hospital admission). Post hoc exploratory analyses of outpatient visits and antibiotic use were also done. Nirsevimab serum concentrations in MEDLEY were assessed using population pharmacokinetic methods and the pooled data from the phase 2b and MELODY trials. An exposure target was defined on the basis of an exposure-response analysis. To successfully demonstrate extrapolation, more than 80% of infants in MEDLEY had to achieve serum nirsevimab exposures at or above the predicted efficacious target.

FINDINGS

Overall, 2350 infants (1564 in the nirsevimab group and 786 in the placebo group) in the phase 2b and MELODY trials were included in the pooled analysis. Nirsevimab showed efficacy versus placebo with respect to the primary endpoint of medically attended RSV LRTI (19 [1%] nirsevimab recipients vs 51 [6%] placebo recipients; relative risk reduction [RRR] 79·5% [95% CI 65·9-87·7]). Consistent efficacy was shown for additional endpoints of RSV LRTI hospital admission (nine [1%] nirsevimab recipients vs 21 [3%] placebo recipients; 77·3% [50·3-89·7]) and very severe RSV (five [<1%] vs 18 [2%]; 86·0% [62·5-94·8]). Nirsevimab recipients had fewer hospital admissions for any-cause respiratory illness (RRR 43·8% [18·8-61·1]), any-cause medically attended LRTI (35·4% [21·5-46·9]), LRTI outpatient visits (41·9% [25·7-54·6]), and antibiotic prescriptions (23·6% [3·8-39·3]). Among infants with chronic lung disease, congenital heart disease, or extreme preterm birth in MEDLEY, nirsevimab serum exposures were similar to those found in the pooled data; exposures were above the target in more than 80% of the overall MEDLEY trial population (94%), including infants with chronic lung disease (94%) or congenital heart disease (80%) and those born extremely preterm (94%).

INTERPRETATION

A single dose of nirsevimab protected healthy infants born at term or preterm from medically attended RSV LRTI, associated hospital admission, and severe RSV. Pharmacokinetic data support efficacy extrapolation to infants with chronic lung disease, congenital heart disease, or extreme prematurity. Together, these data suggest that nirsevimab has the potential to change the landscape of infant RSV disease by reducing a major cause of infant morbidity and the consequent burden on caregivers, clinicians, and health-care providers.

FUNDING

AstraZeneca and Sanofi.

Systematic literature review of the signs and symptoms of respiratory syncytial virus

Respiratory syncytial virus (RSV) is responsible for over 30 million lower respiratory tract infections (LRTIs) and 3 million hospitalizations worldwide each year. Despite the risk RSV poses to young children, older adults, and individuals with comorbidities or suppressed immunity, there is limited understanding of RSV symptom presentation across these at-risk groups, and there is no vaccine for RSV. We conducted two systematic literature reviews (SLRs) of studies that document signs and symptoms (S&S) of RSV in (1) children aged ≤5 years and (2) immunocompromised adolescents and adults, and adults at high risk for severe RSV due to age or comorbidities. Symptom duration and hospital length of stay (LOS) were explored. Electronic database searches were performed following PRISMA guidelines. Studies captured RSV S&S across community and hospital settings. Clinicians and caregivers reported (n = 25 studies) nasal discharge/congestion, cough, shortness of breath, feeding abnormalities, and fever in ≥40% of children across studies and settings. Median hospital stays for children ranged from 2 days in the United States to 7.5 days in China. High-risk adults with RSV (n = 6 studies) commonly (≥40% of adults) reported cough, sputum, dyspnea, and fever/feverishness. Median length of hospital stay in adults ranged from 6 to 15 days across studies. Caregivers and clinicians reported similar RSV S&S in young children, including upper and lower respiratory and systemic symptoms. In high-risk and immunocompromised adults, the most frequent (in multiple publications) and commonly reported RSV S&S were primarily LRTI symptoms. RSV symptoms could last for weeks and are variable based on geography.

Association of viral load with TRAIL, IP-10, CRP biomarker signature and disease severity in children with respiratory tract infection or fever without source: A prospective, multicentre cohort study

BACKGROUND

To investigate the association of viral load (VL) with (i) tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), interferon gamma-induced protein-10, C-reactive protein, and a combinatorial score (BV score), and (ii) clinical severity.

STUDY DESIGN

In this prospective, multicentre cohort substudy, children with respiratory tract infection or fever without source were enrolled. VL for influenza virus, rhinovirus, respiratory syncytial virus, and adenovirus was measured from nasopharyngeal swabs. The reference standard diagnosis was established based on expert panel adjudication.

RESULTS

Of 1140 recruited patients, 333 had a virus monodetection. VL for the aggregated data set correlated with TRAIL and IP-10 levels, with the length of oxygen therapy, and inversely with the BV score. At a single viral level, only the influenza VL yielded a correlation with TRAIL, IP-10 levels, and the BV score. Children with a viral reference standard diagnosis had significantly higher VL than those with bacterial infection (p = 0.0005). Low TRAIL (incidence rate ratio [IRR] 0.6, 95% confidence interval [CI] 0.39-0.91) and young age (IRR 0.62, 95% CI 0.49-0.79) were associated with a longer hospital stay, while young age (IRR 0.33, 95% CI 0.18-0.61), low TRAIL (IRR 0.25, 95% CI 0.08-0.76), and high VL (IRR 1.16, 95% CI 1.00-1.33) were predictive of longer oxygen therapy.

CONCLUSION

These findings indicate that VL correlates with biomarkers and may serve as a complementary tool pertaining to disease severity.

The burden of respiratory syncytial virus in healthy term-born infants in Europe: a prospective birth cohort study

BACKGROUND

Respiratory syncytial virus (RSV) is a major cause of hospitalisation in infants. The burden of RSV infection in healthy term infants has not yet been established. Accurate health-care burden data in healthy infants are necessary to determine RSV immunisation policy when RSV immunisation becomes available.

METHODS

We performed a multicentre, prospective, observational birth cohort study in healthy term-born infants (≥37 weeks of gestation) in five sites located in different European countries to determine the health-care burden of RSV. The incidence of RSV-associated hospitalisations in the first year of life was determined by parental questionnaires and hospital chart reviews. We performed active RSV surveillance in a nested cohort to determine the incidence of medically attended RSV infections. The study is registered with ClinicalTrials.gov, NCT03627572.

FINDINGS

In total, 9154 infants born between July 1, 2017, and April 1, 2020, were followed up during the first year of life and 993 participated in the nested active surveillance cohort. The incidence of RSV-associated hospitalisations in the total cohort was 1·8% (95% CI 1·6-2·1). There were eight paediatric intensive care unit admissions, corresponding to 5·5% of 145 RSV-associated hospitalisations and 0·09% of the total cohort. Incidence of RSV infection in the active surveillance cohort confirmed by any diagnostic assay was 26·2% (24·0-28·6) and that of medically attended RSV infection was 14·1% (12·3-16·0).

INTERPRETATION

RSV-associated acute respiratory infection causes substantial morbidity, leading to the hospitalisation of one in every 56 healthy term-born infants in high-income settings. Immunisation of pregnant women or healthy term-born infants during their first winter season could have a major effect on the health-care burden caused by RSV infections.

FUNDING

Innovative Medicines Initiative 2 Joint Undertaking, with support from the EU's Horizon 2020 research and innovation programme and European Federation of Pharmaceutical Industries and Associations.

Clinical and Socioeconomic Burden of Respiratory Syncytial Virus in Iceland

INTRODUCTION

Respiratory syncytial virus (RSV), a very common pathogen, causes variable disease severity. In addition to considerable clinical burden on children, their families and healthcare facilities, RSV infections in children also carry significant direct and indirect socioeconomic burden.

METHODS

We analyzed data from 5 consecutive RSV seasons (2015-2020) and used virologically confirmed RSV infections and age <5 years as case definition. Clinical information was retrieved from electronic patient records. Costs were estimated by assuming an annual 30% attack rate and a combination of direct medical costs and calculations of societal costs of lost productivity.

RESULTS

A total of 716 children younger than 5 years of age had confirmed RSV infection of which 254 needed hospitalizations, most of whom were previously healthy. The median length of admission was 3.6 days and 13 patients needed intensive care. The hospital admission incidence rate was 2.5/1000 children/year, but 9.1 for children younger than 1 years of age. The total annual cost of RSV was estimated at €4.3 million, of which 10% was direct healthcare costs.

DISCUSSION

The clinical and socioeconomic disease burden of RSV in Iceland is substantial despite slightly lower hospital admission rates than other high-income countries. The prevention of RSV in young children, either through maternal or infant vaccination, has the potential to decrease both clinical and financial impact of the annual epidemics.

Clinical Burden of Respiratory Syncytial Virus in Hospitalized Children Aged ≤5 years (INSPIRE Study)

Background

Respiratory syncytial virus (RSV) is a leading cause of hospitalizations in children (≤5 years of age); limited data compare burden by age.

Methods

This single-center retrospective study included children (≤5 years of age) hospitalized for >24 hours with reverse-transcription polymerase chain reaction (RT-PCR)–confirmed RSV infection (2015–2018). Hospital length of stay (LOS), intensive care unit (ICU) admissions, ICU LOS, supplemental oxygen, and medication use were assessed. Multivariate logistic regression analyses identified predictors of hospital LOS >5 days.

Results

Three hundred twelve patients had RSV infection (ages 0 to <6 months [35%], 6 to <12 months [15%], 1 to <2 years [25%], and 2–5 years [25%]); 16.3% had predefined comorbidities (excludes preterm infants). Median hospital LOS was 5.0 days and similar across age; 5.1% (16/312) were admitted to ICU (ICU LOS, 5.0 days), with those aged 0 to <6 months admitted most frequently (10/108 [9.3%]). Supplemental oxygen was administered in 57.7% of patients, with similar need across ages. Antibiotics were administered frequently during hospitalization (43.6%). Predictors of prolonged LOS included pneumonia (odds ratio [OR], 2.33), supplemental oxygen need (OR, 5.09), and preterm births (OR, 3.37). High viral load (RT-PCR RSV cycle threshold value <25) was associated with greater need for supplemental oxygen.

Conclusions

RSV causes substantial burden in hospitalized children (≤5 years), particularly preterm infants and those aged <6 months.

Prevention of antimicrobial prescribing among infants following maternal vaccination against respiratory syncytial virus

Strategies to reduce consumption of antimicrobial drugs are needed to contain the growing burden of antimicrobial resistance. Respiratory syncytial virus (RSV) is a prominent cause of upper and lower respiratory tract infections, as a single agent and in conjunction with bacterial pathogens, and may thus contribute to the burden of both inappropriately treated viral infections and appropriately treated polymicrobial infections involving bacteria. In a double-blind, randomized, placebo-controlled trial, administering an RSV vaccine to pregnant mothers reduced antimicrobial prescribing among their infants by 12.9% over the first 3 mo of life. Our findings implicate RSV as an important contributor to antimicrobial exposure among infants and demonstrate that this exposure is preventable by use of effective maternal vaccines against RSV.

Reductions in antimicrobial consumption are needed to mitigate the burden of antimicrobial resistance. Vaccines may have an important role to play in reducing antimicrobial consumption by preventing infections for which treatment is often prescribed, whether appropriately or inappropriately. However, limited understanding of the volume of antimicrobial treatment attributable to specific pathogens—and to viruses, in particular—presently hinders efforts to prioritize vaccines with the greatest potential to reduce antimicrobial consumption. In a double-blind trial undertaken across 11 countries, infants born to mothers who were randomized to receive an experimental vaccine against respiratory syncytial virus (RSV) experienced 12.9% (95% CI: 1.3 to 23.1%) lower incidence of antimicrobial prescribing over the first 3 mo of life than infants whose mothers were randomized to receive placebo. Vaccine efficacy against antimicrobial prescriptions associated with acute lower respiratory tract infections (LRTIs) was 16.9% (95% CI: 1.4 to 29.4%). Over the first 3 mo of life, maternal vaccination prevented 3.6 antimicrobial prescription courses for every 100 infants born in high-income countries and 5.1 courses per 100 infants in low- and middle-income countries, representing 20.2 and 10.9% of all antimicrobial prescribing in these settings, respectively. While LRTI episodes accounted for 69 to 73% of all antimicrobial prescribing prevented by maternal vaccination, striking vaccine efficacy (71.3% [95% CI: 28.1 to 88.6%]) was also observed against acute otitis media–associated antimicrobial prescription among infants in high-income countries. Our findings implicate RSV as a cause of substantial volumes of antimicrobial prescribing among young infants and demonstrate the potential for prevention of such prescribing through use of maternal vaccines against RSV.

Respiratory syncytial virus in pediatric influenza-like illness cases in Lombardy, Northern Italy, during seven consecutive winter seasons (from 2014-2015 to 2020-2021)

Introduction

Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract illness in young children and can also cause influenza‐like illness (ILI). Here we investigated the epidemiological features of RSV infection in pediatric ILI cases in Lombardy (a region in Northern Italy accounting nearly 10 million inhabitants) from 2014–2015 to 2020–2021 winter seasons.

Material and Methods

Data for this study were retrieved and statistically analyzed from the database of virological influenza surveillance of the regional reference laboratory for Lombardy within the Italian influenza surveillance network (InfluNet).

Results

RSV accounted for nearly 19% of pediatric ILI with a risk of infection nearly two‐fold greater than that of individuals ≥15 years. RSV positivity rate increased to 28% considering 0–5 years old children. Although in children ≤5 years the risk of infection from influenza viruses resulted nearly two‐fold higher than the risk of RSV infection, the age group 4–6 months and 7–12 months showed a five‐fold greater risk of infection from RSV than from influenza. Children ≤5 years of age with pre‐existing underlying health conditions had a nearly five‐fold greater risk of getting RSV infection than otherwise healthy 0–5 years old children. RSV was identified in ILI cases <15 years of age in all considered winter seasons except in the 2020–2021 season.

Discussion

Sentinel surveillance of ILI allowed us to identify groups at higher risk of RSV and influenza infection and to define the start, duration, timing, and intensity of the RSV and influenza community circulation. This surveillance approach can be implemented to assess the RSV circulation and impact in a real‐time manner.

Evaluation of a standardised protocol to measure the disease burden of respiratory syncytial virus infection in young children in primary care

Background

A better understanding of the burden of respiratory syncytial virus (RSV) infections in primary care is needed for policymakers to make informed decisions regarding new preventive measures and treatments. The aim of this study was to develop and evaluate a protocol for the standardised measurement of the disease burden of RSV infection in primary care in children aged < 5 years.

Methods

The standardised protocol was evaluated in Italy and the Netherlands during the 2019/20 winter. Children aged < 5 years who consulted their primary care physician, met the WHO acute respiratory infections (ARI) case definition, and had a laboratory confirmed positive test for RSV (RT-PCR) were included. RSV symptoms were collected at the time of swabbing. Health care use, duration of symptoms and socio-economic impact was measured 14 days after swabbing. Health related Quality of life (HRQoL) was measured using the parent-proxy report of the PedsQL™4.0 generic core scales (2–4 years) and PedsQL™4.0 infant scales (0–2 years) 30 days after swabbing. The standardised protocol was evaluated in terms of the feasibility of patient recruitment, data collection procedures and whether parents understood the questions.

Results

Children were recruited via a network of paediatricians in Italy and a sentinel influenza surveillance network of general practitioners in the Netherlands. In Italy and the Netherlands, 293 and 152 children were swabbed respectively, 119 and 32 tested RSV positive; for 119 and 12 children the Day-14 questionnaire was completed and for 116 and 11 the Day-30 questionnaire. In Italy, 33% of the children had persistent symptoms after 14 days and in the Netherlands this figure was 67%. Parents had no problems completing questions concerning health care use, duration of symptoms and socio-economic impact, however, they had some difficulties scoring the HRQoL of their young children.

Conclusion

RSV symptoms are common after 14 days, and therefore, measuring disease burden outcomes like health care use, duration of symptoms, and socio-economic impact is also recommended at Day-30. The standardised protocol is suitable to measure the clinical and socio-economic disease burden of RSV in young children in primary care.

Global burden of upper respiratory infections in 204 countries and territories, from 1990 to 2019

BACKGROUND

Upper respiratory infections (URIs) are among the most common diseases. However, the related burden has not been comprehensively evaluated. Thus, we designed the present study to describe the global and regional burden of URIs from 1990 to 2019.

METHODS

A secondary analysis was performed on the incidence, mortality, and disability-adjusted life years (DALYs) of URIs in different sex and age groups, from 21 geographic regions, 204 countries and territories, between 1990 and 2019, using the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Countries and territories were categorized according to Socio-demographic Index (SDI) quintiles.

FINDINGS

Globally, the incident cases of URIs reached 17·2 (95% uncertainty interval: 15·4 to 19·3) billion in 2019, which accounted for 42·83% (40·01% to 45·77%) cases from all causes in the GBD 2019 study. The age-standardized incidence rate remained stable from 1990 to 2019, while significant decreases were found in the mortality and DALY rate. The highest age-standardized incidence rates from 1990 to 2019 and the highest age-standardized DALY rates after 2011 were observed in high SDI regions. Among all the age groups, children under five years old suffered from the highest incidence and DALY rates, both of which were decreased with increasing age. Fatal consequences of URIs occurred mostly in the elderly and children under five years old.

INTERPRETATION

The present study provided comprehensive estimates of URIs burden for the first time. Our findings, highlighting the substantial incidence and considerable DALYs due to URIs, are expected to attract more attention to URIs and provide future explorations in the prevention and treatment with epidemiological evidence.

FUNDING

The study was funded by the National Natural Science Foundation of China (81770057).

Role of G2-S16 Polyanionic Carbosilane Dendrimer in the Prevention of Respiratory Syncytial Virus Infection In Vitro and In Vivo in Mice

The respiratory syncytial virus (RSV) causes respiratory infection and bronchiolitis, requiring hospitalization mainly in infants. The interaction between RSV, envelope glycoproteins G and F, and cell surface heparan sulfate proteoglycans (HSPG) is required for binding and entry into the host cells. A G2-S16 polyanionic carbosilane dendrimer was identified as a possible RSV inhibitor. We speculated that the G2-S16 dendrimer adheres to the host cell-surface HSPG, acts through binding to HS receptors, and prevents further RSV infection. The G2-S16 dendrimer was non-toxic when applied intranasally to Balb/c mice, and interestingly enough, this G2-S16 dendrimer inhibits 85% RSV. Therefore, our G2-S16 dendrimer could be a candidate for developing a new possible therapy against RSV infection.

Clinico demographic profiling of the Respiratory syncytial virus (RSV) infected children admitted in tertiary care hospital in North India

Background:

Acute bronchiolitis is fatal disease involving lower respiratory tract of infants and children of paediatric age group. Respiratory Syncytial Virus (RSV) is responsible for causing more than 70% hospital admissions of children aged less than 2 years thus making a necessity for accurate and timely diagnosis.

Aims:

The main aim of study was clinicodemographic correlation of RSV positive children presenting to our tertiary care hospital.

Setting and Design:

It is a retrospective study done between December to January 2018.

Materials and Methods:

Detection of RSV antigen from nasophyrangeal aspirates using Mouse Monoclonal anti RSV Antibody (by Novatetra) and Goat Anti Mouse Antibody conjugated with FITC as secondary antibody.

Results:

A total of 147 samples were received in the laboratory and 20 were tested as positive for RSV Antigen. Totally, 19/20 children were aged less than 1 year and with a male predominance. The most common symptom was cough and respiratory distress. Eight percent of the children showed wheezing and 18/20 required assisted ventilation. The clinical course in one child deteriorated leading to death of that patient.

Conclusions:

The timely diagnosis and management of RSV infected children is utmost needed to prevent morbidity and mortality. The premorbid conditions can assist to differentiate the viral from bacterial pneumonia and thus enable speedy recovery of the child.