A new tool has been developed to help identify newborns at highest risk for developing serious respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI). This tool may be useful in allocating limited immunoprophylaxis, such as nirsevimab or palivizumab, for RSV prevention among high-risk infants. Early immunization with nirsevimab is recommended for all infants by the Centers for Disease Control & Prevention, but a shortage of nirsevimab in October 2023 led to restrictions on its use for only high-risk infants. The new tool, developed by researchers at Vanderbilt University Medical Center, aims to predict which infants are at risk of severe RSV LRTI requiring intensive care unit (ICU) admission in the first year of life.
The population-based study included infants insured by the Tennessee Medicaid Program and assessed infants who did not receive RSV immunoprophylaxis in the first year of life. Researchers collected demographic and clinical data, including prenatal smoking, delivery method, maternal age, and assisted breathing during birth hospitalization. A multivariable logistic regression model was developed to predict the risk of severe RSV LRTI requiring ICU admission, with good predictive accuracy and internal validation indicating a good fit. The tool was designed for use in all infants using readily available birth and postnatal data to prioritize RSV prevention products during times of limited availability.
The personalized risk prediction tool may help prioritize RSV prevention measures in newborns, especially during times of limited availability of RSV prevention medicines. It may also be useful in persuading vaccine-hesitant families to accept RSV immunoprophylaxis by showing them that their newborn is at high risk for severe RSV infection requiring ICU care. The tool was developed for use in all infants to ensure compatibility with nirsevimab and maternal vaccination and may be beneficial in countries with budgetary constraints needing to prioritize administration to the highest risk infants.
The authors suggest that next steps to ensure the optimal usefulness of the tool include validation in external populations, further cost-effectiveness analyses, and decision curve analyses. While the recent shortage of nirsevimab has eased, it is unknown whether shortages will occur in the future. Therefore, the tool may be valuable in identifying high-risk infants for RSV prevention during times of limited availability of RSV prevention medicines. The research has potential implications for improving RSV prevention strategies and protecting high-risk infants from severe RSV infections.