Respiratory syncytial virus in preterm infants: 19 years of active epidemiological surveillance in a children's hospital

Abstract

Introduction. Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infection (ALRTI) in pediatrics. Preterm infants are at a higher risk for complications. We aimed to describe and compare the clinical and epidemiological characteristics associated with ALRTI due to RSV in preterm and term infants and to establish the predictors of fatality among preterm infants. Methods. Prospective, cross-sectional study of patients admitted due to ALRTI in the 2000-2018 period. Viral diagnosis was done by indirect immunofluorescence or reverse transcription polymerase chain reaction in nasopharyngeal aspirates. Clinical and epidemiological characteristics were recorded. A multiple logistic regression model established the predictors of fatality among preterm infants. Results. A total of 16 018 ALRTI cases were included; 13 545 (84.6 %) were tested; 6047 (45 %) were positive; RSV was prevalent in 81.1 % (4907), with a seasonal epidemic pattern; 14 % (686) were preterm infants. Comorbidities, perinatal respiratory history, congenital heart disease, malnutrition, chronic respiratory disease, bronchopulmonary dysplasia, prior hospitalization due to ALRTI, and chronic neurological disease (p < 0.001) were more common among preterm infants; they required more intensive care and a longer length of stay, and had a higher fatality rate (p < 0.01). Congenital heart disease was an independent predictor of fatality due to RSV among preterm infants (OR: 3.67 [1.25-10.8], p = 0.01). Conclusion. RSV showed an epidemic pattern and affected more preterm infants with certain comorbidities, with a higher morbidity and mortality, compared to term infants. RSV fatality among preterm infants was associated with congenital heart disease.