RSV bronchiolitis season 2021 has arrived, so be prepared!

Efficacy and safety of bivalent RSVpreF maternal vaccination to prevent RSV illness in Japanese infants: Subset analysis from the pivotal randomized phase 3 MATISSE trial

BACKGROUND

Maternal vaccination with respiratory syncytial virus prefusion F vaccine (RSVpreF) is effective at preventing RSV-associated lower respiratory tract illness (LRTI) in newborns/infants.

METHODS

This subgroup analysis from the global, phase 3, randomized, double-blind, placebo-controlled MATISSE (Maternal Immunization Study for Safety and Efficacy) trial evaluated participants enrolled in Japan. Pregnant women 24-36 weeks' gestation were randomized 1:1 to receive RSVpreF or placebo. Maternal safety endpoints included local reactions/systemic events within 7 days, adverse events (AEs) through 1 month, and serious AEs (SAEs) through 6 months after vaccination. In infants born to maternal participants, safety endpoints included specific birth outcomes, AEs through 1 month after birth, and SAEs and newly diagnosed chronic medical conditions through 12 or 24 months after birth. Vaccine efficacy in infants was assessed against RSV-positive, medically attended LRTI (RSV-MA-LRTI) and severe RSV-MA-LRTI through 180 days after birth.

RESULTS

In Japan, 230 maternal participants received RSVpreF and 232 received placebo; 218 and 216 infants born to these mothers, respectively, were analyzed. Observed vaccine efficacy (95 % CIs) against infant RSV-MA-LRTI within 90 and 180 days after birth was 100.0 % (30.9, 100.0; RSVpreF, 0 cases; placebo, 7 cases) and 87.6 % (7.2, 99.7; RSVpreF, 1 case; placebo, 8 cases), respectively. Vaccine efficacy (95 % CIs) against severe RSV-MA-LRTI within 90 and 180 days was 100.0 % (-140.9, 100.0; RSVpreF, 0 cases; placebo, 3 cases) and 75.1 % (-151.5, 99.5; RSVpreF, 1 case; placebo, 4 cases), respectively. No safety concerns were identified. AE rates ≤1 month after vaccination/birth were similar in the RSVpreF (maternal, 16.1 %; infant, 48.6 %) and placebo (19.8 %; 50.5 %) groups. Preterm birth rates were also similar (RSVpreF, 3.2 %; placebo, 6.0 %).

CONCLUSIONS

Safety and efficacy data in Japanese participants were consistent with overall MATISSE results, supporting the efficacy of maternal RSVpreF vaccination against severe MA-RSV-LRTI/MA-RSV-LRTI in infants, with no safety concerns. NCT04424316.

Identifying the impact of non-pharmaceutical interventions on RSV transmission in a single-centre observational study

During the COVID-19 pandemic, the introduction of non-pharmaceutical interventions (NPIs) resulted in an unprecedented reduction in the transmission of the respiratory syncytial virus (RSV), the predominant cause of bronchiolitis. As NPIs were eased, it was speculated that RSV transmission would return with an increase in the severity of bronchiolitis. In a large tertiary hospital, a dramatic reduction in the incidence of bronchiolitis was seen during the COVID-19 pandemic. The easing of NPIs correlated with an increase in RSV transmission particularly in the community; however, there was no evidence of an increase in the severity of bronchiolitis.

Evaluation of Severe Acute Respiratory Syndrome surveillance caused by respiratory viruses in a pediatric unit, 2013 to 2019

OBJECTIVE

To evaluate severe acute respiratory syndrome surveillance in a pediatric unit.

METHODS

Descriptive study of reported severe acute respiratory syndrome cases with the detection of respiratory viruses in the nasopharyngeal sample of patients hospitalized between 2013 and 2019, in a reference hospital in the Federal District, Brazil.

RESULTS

A total of 269 children had one or more viruses detected, resulting in 280 viruses, of which 152 (54%) were respiratory syncytial virus. The detection of respiratory syncytial virus was higher during the autumn-winter period. Children´s median age was 6.9 months, 156 (58%) were male, 104 (39%) had comorbidity, 197 (73%) required mechanical ventilation, 241 (90%) received antibiotics, and 146 (54%) oseltamivir. There were 19 (7%) deaths. The median time from symptom onset to sample collection was 5 days and the median time from sample collection to final results was 6 days.

CONCLUSIONS

The system needs to reduce the time to deliver results so that inappropriate use of antibiotics and antivirals can be avoided. Moreover, the burden of viral pneumonia was relevant and the system must be flexible enough to include emerging viruses in order to be useful in responding to public health emergencies caused by respiratory viruses.

Vaccine-Preventable Hospitalisations from Seasonal Respiratory Diseases: What Is Their True Value?

Hospitals in England experience extremely high levels of bed occupancy in the winter. In these circumstances, vaccine-preventable hospitalisations due to seasonal respiratory infections have a high cost because of the missed opportunity to treat other patients on the waiting list. This paper estimates the number of hospitalisations that current vaccines against influenza, pneumococcal disease (PD), COVID-19, and a hypothetical Respiratory Syncytial Virus (RSV) vaccine, could prevent in the winter among older adults in England. Their costs were quantified using a conventional reference costing method and a novel opportunity costing approach considering the net monetary benefit (NMB) obtained from alternative uses of the hospital beds freed-up by vaccines. The influenza, PD and RSV vaccines could collectively prevent 72,813 bed days and save over £45 million in hospitalisation costs. The COVID-19 vaccine could prevent over 2 million bed days and save £1.3 billion. However, the value of hospital beds freed up by vaccination is likely to be 1.1-2 times larger (£48-93 million for flu, PD and RSV; £1.4-2.8 billion for COVID-19) when quantified in opportunity cost terms. Considering opportunity costs is key to ensuring maximum value is obtained from preventative budgets, as reference costing may significantly underestimate the true value of vaccines.

The bronchiolitis epidemic in 2021-2022 during the SARS-CoV-2 pandemic: experience of a third level centre in Northern Italy

BACKGROUND

The aim of this study is to compare the 2021-2022 bronchiolitis season to the four previous years (2017-2018, 2018-2019, 2019-2020, 2020-2021) to see if there was an anticipation of the peak, an overall increase of cases, and an increased need of intensive care.

METHODS

A retrospective single-centre study in the San Gerardo Hospital Fondazione MBBM, Monza, Italy was performed. Emergency Departments (ED) visits of patients aged < 18 years and ≤ 12 months were analyzed: the incidence of bronchiolitis on total assessments, the urgency level at triage and the hospitalization rate were compared. Data of children admitted to the Pediatric Department due to bronchiolitis were analyzed in terms of need of intensive care, respiratory support (type and duration), length of hospital stay, main etiological agent, patient characteristics.

RESULTS

During 2020-2021 (first pandemic period) an important reduction in the ED attendance for bronchiolitis was observed, while in 2021-2022 there was an increase in incidence of bronchiolitis (13% of visits in infants < 1 year) and in the rate of urgent accesses (p = 0.0002), but hospitalization rates did not differ compared to previous years. Furthermore, an anticipated peak in November 2021 was observed. In the 2021-2022 cohort of admitted children to the Pediatric Department, a statistically significative increased need of intensive care unit was detected (Odds Ratio 3.1, 95% CI 1.4-6.8 after adjustment for severity and clinical characteristics). Instead, respiratory support (type and duration) and length of hospital stay did not differ. RSV was the main etiological agent and RSV-bronchiolitis determined a more severe infection (type and duration of breathing support, intensive care need and length of hospital stay).

CONCLUSIONS

During Sars-CoV-2 lockdowns (2020-2021), there was a dramatic decrease of bronchiolitis and others respiratory infections. In the following season, 2021-2022, an overall increase of cases with an anticipated peak was observed and data analysis confirmed that patients in 2021-2022 required more intensive care than children in the four previous seasons.

RSV through the COVID-19 pandemic: Burden, shifting epidemiology, and implications for the future

Respiratory syncytial virus (RSV) represents a major global healthcare burden, particularly in those under 5 years of age. There is no available vaccine, with treatment limited to supportive care or palivizumab for high-risk children. Additionally, although a causal relationship has not been established, RSV has been associated with the development of asthma or wheezing in some children. The COVID-19 pandemic and the introduction of nonpharmaceutical interventions (NPIs) have caused substantial changes to RSV seasonality and epidemiology. Many countries have experienced an absence of RSV during the time of a typical season, followed by an out-of-season surge upon relaxation of NPI use. These dynamics have disrupted traditional RSV disease patterns and assumptions, but also provide a unique opportunity to learn more about the transmission of RSV and other respiratory viruses, as well as inform future approaches to RSV preventive strategies. Here, we review the RSV burden and epidemiology through the COVID-19 pandemic and discuss how new data may affect future decisions regarding RSV prevention.

Parents Reaching Out to Parents: An Appreciative, Qualitative Evaluation of Stakeholder Experiences of the Parent Champions in the Community Project

Background: Bronchiolitis is a seasonal, global acute lower respiratory tract infection caused by respiratory syncytial virus (RSV) and is a leading cause of hospital admission in young children. A peer-led (parents to parents) intervention was implemented to empower parents of children at risk of bronchiolitis and reduce hospital admissions. This paper reported the evaluation that aimed to gain the perspectives and experiences of five key stakeholder groups. Methods: A qualitative remote interview-based design, informed by Appreciative Inquiry was used. Thematic analysis was used. Results: Sixty-five stakeholders participated: parents (n = 43; mothers, n = 42), Parent Champions (n = 9), Children’s Centre Managers (n = 8), Children’s Centre Group Leaders (n = 11), and Core Team (n = 4). An overarching theme ‘Parents reaching out to parents’ was supported by five sub-themes (Raising awareness and sharing knowledge; Creating connection, trust, and confidence; Flourishing in their role as a Parent Champion; Rising to the challenges; and Knowledge is power, prevention is key: the government needs to know this.) Conclusions: Parent-to-parent peer support via the Parent Champions was perceived positively by parents who wanted to learn and improve the lives and health of their children. Parent Champions were successful in delivering information. Considering the socioeconomic burden of bronchiolitis to services and families, the potential for an upstream, relatively low cost, high-reach innovative intervention, as evidenced in this project, seems a valuable opportunity for improving children’s respiratory health.

From COVID-19 to Influenza-Real-Life Clinical Practice in a Pediatric Hospital

The COVID-19 pandemic, through the restrictions and the non-pharmaceutical interventions implemented, has importantly impacted the circulation and epidemiology of respiratory viruses. Specifically, the 2020/21 season was entirely dominated by SARS-CoV-2, while influenza activity reached an all-time low, despite initial warnings that a double concurrent epidemic could be possible. The current season, 2021/22, started with the shift of circulating SARS-CoV-2 variants from delta to omicron, which then rapidly spread globally, as most countries, including Romania, removed all restrictions and compulsory non-pharmaceutical interventions. In this report we present the clinical reality observed in March 2022 in a tertiary paediatric hospital in Bucharest, Romania, where we observed a sudden surge in influenza cases, after two consecutive years (March 2020 to March 2022) when influenza had stopped circulating in our country. Thus, in March 2022 the positivity rate of rapid influenza antigen tests unexpectedly increased to 33.5%, paralleled by a decrease to 7.5% in the positivity rate of rapid SARS-CoV-2 antigen tests. This significant increase in the influenza attack rate was observed from the first week (14.9% positivity rate), through the fourth week of March (42.1% positivity rate, p < 0.001), while the COVID-19 attack rate displayed a significant decreasing trend (from 11.2% to 4.8%, p < 0.001). These data serve as a warning about relaxing restrictions in a precipitous approach with minimised vigilance. The evolution of these observations needs to be followed very carefully in all countries, particularly in settings where epidemiological interactions and non-pharmaceutical interventions have so far led to the extensive circulation of only one of these viruses, and we should now be prepared to perform a correct differential diagnosis between influenza and COVID-19, in order to ensure the best quality of care and personalized management of each case of respiratory infection. The results of active influenza surveillance studies for the whole 2021/22 season are awaited, in order to quantify the joint influenza—COVID-19 burden among children.

Modeling the disruption of respiratory disease clinical trials by non-pharmaceutical COVID-19 interventions

Respiratory disease trials are profoundly affected by non-pharmaceutical interventions (NPIs) against COVID-19 because they perturb existing regular patterns of all seasonal viral epidemics. To address trial design with such uncertainty, we developed an epidemiological model of respiratory tract infection (RTI) coupled to a mechanistic description of viral RTI episodes. We explored the impact of reduced viral transmission (mimicking NPIs) using a virtual population and in silico trials for the bacterial lysate OM-85 as prophylaxis for RTI. Ratio-based efficacy metrics are only impacted under strict lockdown whereas absolute benefit already is with intermediate NPIs (eg. mask-wearing). Consequently, despite NPI, trials may meet their relative efficacy endpoints (provided recruitment hurdles can be overcome) but are difficult to assess with respect to clinical relevance. These results advocate to report a variety of metrics for benefit assessment, to use adaptive trial design and adapted statistical analyses. They also question eligibility criteria misaligned with the actual disease burden.

Exclusive Breastfeeding and Vitamin D Supplementation: A Positive Synergistic Effect on Prevention of Childhood Infections?

Human milk is the best food for infants. Breastfeeding has been associated with a reduced risk of viral and bacterial infections. Breast milk contains the perfect amount of nutrients needed to promote infant growth, except for vitamin D. Vitamin D is crucial for calcium metabolism and bone health, and it also has extra-skeletal actions, involving innate and adaptive immunity. As exclusive breastfeeding is a risk factor for vitamin D deficiency, infants should be supplemented with vitamin D at least during the first year. The promotion of breastfeeding and vitamin D supplementation represents an important objective of public health.

The return of RSV during the COVID-19 pandemic

Respiratory syncytial virus (RSV) hospitalizations practically disappeared in 2020. Now, with Southern Hemisphere 2021 winter behind us, RSV has returned. Despite it is difficult to weigh the impact of pandemic mitigation measures on common respiratory virus circulation, it appears that acute respiratory infections in children are returning to their usual epidemiology.

Clinical severity of RSV bronchiolitis

Background

Studies comparing the severity of respiratory syncytial virus (RSV) bronchiolitis to other viruses are inconclusive. Our study aimed to compare the severity of bronchiolitis according to the virus.

Methods

Data were collected from 1152 infants under one year of age admitted to Children's hospital for Wales, over the winter months of 2014-2020. The cohort was divided based on the virus detected: RSV, RSV with another virus, or other virus. Using t tests and Fisher exact statistical test, the groups were compared based on length of hospital stay, admissions PICU/HDU, intubations, and need of nasogastric (NG) nutritional support.

Results

Fifty-six percent throat swabs were RSV positive, 15% had RSV with another virus, and 29% had only another virus. Children positive for RSV had statistically longer hospital admissions and were more likely to need NG nutrition; however, there was no difference between number of PICU/HDU admissions or intubations. The RSV group and RSV with another virus group had no statistical differences.

Population-based study of influenza and invasive meningococcal disease among Greek children during the COVID-19 pandemic

BACKGROUND

Aiming to the containment of the coronavirus disease 2019 (COVID-19) pandemic, governments worldwide have implemented a series of non-pharmaceutical interventions. Many of them and especially school closures have impacted the circulation of multiple airborne pathogens among children and adolescents. This study investigates the incidence of influenza and invasive meningococcal disease among children aged 0-14 years in Greece during the COVID-19 pandemic.

METHODS

Data regarding the number of influenza-like illness cases, influenza-related paediatric intensive care unit (PICU) admissions and invasive meningococcal disease cases among children 0-14 years old were obtained from the National Public Health Organization. The incidence of the two diseases during the COVID-19 pandemic period (2020/2021) was compared with that of the six preceding seasons (2014-2019).

RESULTS

A notable decrease was observed in both influenza and invasive meningococcal disease cases during the period 2020/2021 compared with the years 2014-2019. The mean annual rate of influenza-like illness cases and influenza-related PICU admissions in children 0-14 years old has reduced by 66.9% and 100%, respectively, while the mean annual invasive meningococcal disease rate has declined by 70%. Both weekly influenza-like illness and monthly invasive meningococcal disease rates were significantly decreased.

CONCLUSIONS

The activity of influenza and invasive meningococcal disease in the children and adolescents of Greece has decreased during the COVID-19 pandemic period. Reduced transmission is likely related to the public health measures that were implemented to control the pandemic. The value of these measures may have relevance to the future management of influenza or invasive meningococcal disease epidemics.

The Impact of the COVID-19 Pandemic Lockdown on Pediatric Infections—A Single-Center Retrospective Study

Since the SARS-CoV-2 outbreak, many countries have introduced measures to limit the transmission. The data based on ICD-10 codes of lower respiratory tract infections and microbiological analysis of respiratory and gastrointestinal infections were collected. The retrospective five-year analysis of the medical records revealed a substantial decrease in respiratory tract infections during the pandemic year (from April 2020 to March 2021). We noted an 81% decline in the LRTI-associated hospital admissions based on the ICD-10 analysis (from a mean of 1170 admissions per year in the previous four years to 225 admissions between April 2020 through March 2021). According to microbiological analysis, there were 100%, 99%, 87%, and 47% drops in influenza virus, respiratory syncytial virus, rotavirus, and norovirus cases reported respectively during the pandemic season until April 2021 in comparison to pre-pandemic years. However, the prevalence of gastrointestinal bacterial infections was stable. Moreover, in August 2021, an unexpected rise in RSV-positive cases was observed. The measures applied during the COVID-19 pandemic turned out to be effective but also had a substantial contribution to the so-far stable epidemiological situation of seasonal infections.