How has the SARS-CoV-2 pandemic changed the epidemiology and management of acute bronchiolitis?

Seasonality of the incidence of bronchiolitis in infants - Brazil, 2016-2022: An interrupted time-series analysis

OBJECTIVE

To evaluate the seasonality of acute bronchiolitis in Brazil during the 2020-2022 season and compare it with the previous seasons.

METHODS

Data from the incidence of hospitalizations due to acute bronchiolitis in infants <1 year of age were obtained from the Department of Informatics of the Brazilian Public Health database for the period between 2016 and 2022. These data were also analyzed by macro-regions of Brazil (North, Northeast, Southeast, South, and Midwest). To describe seasonal and trend characteristics over time, we used the Seasonal Autoregressive Integrated Moving Averages Model.

RESULTS

Compared to the pre-COVID-19 period, the incidence of hospitalizations related to acute bronchiolitis decreased by 97% during non-pharmacological interventions (March 2020 - August 2021) but increased by 95% after non-pharmacological interventions relaxation (September 2021 - December 2022), resulting in a 16% overall increase. During the pre-COVID-19 period, hospitalizations for acute bronchiolitis followed a seasonal pattern, which was disrupted in 2020-2021 but recovered in 2022, with a peak occurring in May, approximately 4% higher than the pre-COVID-19 peak.

CONCLUSIONS

This study underscores the significant influence of COVID-19 interventions on acute bronchiolitis hospitalizations in Brazil. The restoration of a seasonal pattern in 2022 highlights the interplay between public health measures and respiratory illness dynamics in young children.

The increase of bronchiolitis severity in the 2022-2023 season in an Italian tertiary children's hospital: An isolated phenomenon or a warning sign?

AIM

Recent literature has shown epidemiological changes in bronchiolitis with an increased incidence in the post-SARS-CoV-2 pandemic period but reports regarding disease severity are conflicting. We aimed to describe the epidemiology, disease severity, and microbiology of bronchiolitis during the 2022-2023 cold season compared to the previous 5 years.

METHODS

This single-center retrospective observational study at IRCCS Gaslini, Italy, included all children aged 0-2 years hospitalized for bronchiolitis from 1 September 2017 to 31 August 2023. Findings from the 2022-2023 season were compared to the previous 5 years.

RESULTS

We observed a statistically significant increase in the 2022-2023 season in the absolute number of bronchiolitis admissions. Children who required mechanical ventilation (MV) dramatically increased from a total of seven patients in the previous five seasons to 17 in the 2022-2023 season alone (p = .001). All other severity parameters significantly increased: the need for respiratory support (p = .002), the median length of stay (5 days vs. 4 days, p = .001), and the median duration of respiratory support (4 days vs. 3 days, p = .016).

CONCLUSIONS

We report a substantial increase in the severity of bronchiolitis in the season 2022-2023 with a remarkable number of previously healthy infants requiring MV. Further studies are needed to confirm whether our findings are an isolated phenomenon or part of a true global trend. Health systems need to be prepared and protective preventive measures should be implemented for all newborns.

Urgent Hospitalizations Related to Viral Respiratory Disease in Children during Autumn and Winter Seasons 2022/2023

AIM

The loosening of social distancing measures over the past two years has led to a resurgence of seasonal epidemics associated with respiratory viral infections in children. We aim to describe the impact of such infections through urgent hospitalizations in a pediatric emergency department.

METHODS

We performed a retrospective review of medical records of all children and adolescents with a positive nasal swab admitted at the children's hospital IRCCS Burlo Garofolo of Trieste, in Italy, from September 2021 to March 2022, and September 2022 to March 2023.

RESULTS

Respiratory Syncytial Virus and Influenza viruses accounted for up to 55% of hospitalizations for respiratory infections during the study periods. During the last season, the number of hospitalizations related to the Influenza virus was five times higher than those related to SARS-CoV-2 (25% vs. 5%). Respiratory Syncytial Virus was associated with a greater need for respiratory support, mostly HFNC (High Flow Nasal Cannula).

CONCLUSIONS

Respiratory Syncytial Virus and Influenza virus had a more significant impact on urgent hospitalizations during the past wintery seasons than SARS-CoV-2.

Severe bronchiolitis profiling as the first step towards prevention of asthma

Bronchiolitis is the most common respiratory infection leading to hospitalization and constitutes a significant healthcare burden. The two main viral agents causing bronchiolitis, respiratory syncytial virus (RSV) and rhinovirus (RV), have distinct cytopathic, immune response, and clinical characteristics. Different approaches have been suggested for subtyping bronchiolitis based on viral etiology, atopic status, transcriptome profiles in blood, airway metabolome, lipidomic data, and airway microbiota. The highest risk of asthma at school age has been in a subgroup of bronchiolitis characterized by older age, high prevalence of RV infection, previous breathing problems, and/or eczema. Regarding solely viral etiology, RV-bronchiolitis in infancy has been linked to a nearly three times higher risk of developing asthma than RSV-bronchiolitis. Although treatment with betamimetics and systemic corticosteroids has been found ineffective in bronchiolitis overall, it can be beneficial for infants with severe RV bronchiolitis. Thus, there is a need to develop a more individualized therapeutic approach for bronchiolitis and follow-up strategies for infants at higher risk of asthma in the future perspective.