Burden and Characteristics of Respiratory Syncytial Virus-Associated Bronchiolitis in Hospitalized Infants in Italy: A Systematic Review.

BACKGROUND

Respiratory syncytial virus (RSV) is the main cause of bronchiolitis in infants. This systematic review aimed to evaluate the burden of RSV-associated bronchiolitis among hospitalized Italian infants between 2000 and 2023.

METHODS

A comprehensive literature search identified studies examining RSV-related hospitalizations for bronchiolitis in children aged 0-59 months. Eligible studies met the following criteria: conducted in Italy, focused on children, reported on RSV prevalence, co-infections, genotype distribution (RSV-A, RSV-B), and seasonal trends, and published in English or Italian. Data extraction focused on study design, infant characteristics (e.g., age, preterm birth), and RSV detection methods.

RESULTS

Twenty-four studies were included. Infants under 12 months were most affected. RSV was the primary pathogen identified, though co-infections with other respiratory viruses, such as human rhinovirus, were common. RSV infections typically peaked in late autumn and winter, but the COVID-19 pandemic altered these patterns. This review highlights the significant burden of RSV-associated bronchiolitis in Italian infants. While RSV remains the primary pathogen, co-infections and pandemic related factors have altered its epidemiological trends.

CONCLUSIONS

Nationwide RSV immunization programmes and improved diagnostics are crucial to ease the strain on pediatric intensive care units. Recent recommendations for widespread RSV long-acting monoclonal antibody use in infants offer promising solutions to address this challenge.