Factors associated with severe respiratory syncytial virus infection among hospitalized children in Thammasat University Hospital

Abstract

Background Respiratory syncytial virus (RSV) is one of the most significant respiratory pathogens that causes acute lower respiratory tract infections (LRTI) early in life. Most children have a history of RSV infection within 24 months of age, and recurrent infections are common throughout life. Methods Children under five years of age were identified through a review of medical records with a diagnosis of RSV-LRTI between 2016 and 2020. Severe RSV-LRTI was defined as a prolonged length of stay (> 7 days), admission to the intensive care unit, need for mechanical ventilation, non-invasive positive pressure ventilation, or in-hospital mortality. Factors associated with severe RSV-LRTIs were investigated using univariate and multivariate analyses. Results During the study period, 620 patients were diagnosed with RSV-LRTI and 240 (40.16%) patients had severe RSV-LRTI. In the multivariable logistic regression analysis, the factors for severe RSV-LRTI were being under 3 months (aOR 2.18 CI 1.39-3.43, p0.001), cardiovascular disease (aOR 3.55 CI 1.56-8.06, p0.002), gastrointestinal disease (aOR 5.91 CI 1.90-18.46, p0.002), genetic disease (aOR 7.33 CI 1.43-37.54, p0.017), and pulmonary disease (aOR 9.50, CI 4.56-19.80, p<0.001). Additionally, the presence of ≥ 2 co-morbidities (aOR 6.23 CI 2.81-14.81, p<0.016), experiencing illness for more than 5 days (aOR 3.33 CI 2.19-5.06, p<0.001), co-detection of influenza (aOR 8.62 CI 1.49-38.21, p0.015), and nosocomial RSV infection (aOR 9.13 CI 1.98-41.30, p0.012), markedly increased the risk of severe RSV-LTRI. The severe RSV-LRTI group demonstrated higher hospitalization expenses (median, US $720.77 vs $278.00, respectively; p<0.001), and three infants died in-hospital. Conclusion Children at high risk for RSV-LRTI due to underlying genetic and gastrointestinal diseases are at an increased risk for severe RSV-LRTI. Further studies to determine the cost-effectiveness of RSV immunization in these potential co-morbidities should be initiated to prioritize RSV immunization, especially in resource-constrained regions with limited availability of nirsevimab.