Respiratory Syncytial Virus in Otherwise Healthy Prematurely Born Infants: A Forgotten Majority

Abstract

Healthy, premature infants ≤35 weeks' gestational age (wGA) are universally recognized to be at an increased risk of perinatal morbidity and mortality. Serious respiratory syncytial virus (RSV) lower respiratory tract infection imposes an additional burden of illness on these infants following hospitalization. Incurred morbidities relative to term infants include longer lengths of hospital stay, admission to intensive care, and need for oxygen and mechanical ventilation, all of which are associated with increased hospital costs. The highest morbidities are experienced by premature infants who are youngest (<3 months' chronological age) and are of lower gestational age. Short- and long-term follow-up indicates that healthy preterm infants both of lower gestational age and who are late preterm have obstructive lung function at baseline, which is further compromised by RSV-related infection during infancy. There is increasing evidence that childhood exposure to an episode of RSV infection may set the stage for an abnormal respiratory function trajectory, which, in adulthood, leads to chronic obstructive pulmonary disease. Healthy premature infants <32 wGA merit RSV prophylaxis based on existing data, whereas moderate- and high-risk preterm infants 32 to 35 wGA should be selectively and cost-effectively targeted for prophylaxis using validated risk scoring tools and country-specific thresholds for funding.

Clinical burden of severe respiratory syncytial virus infection during the first 2 years of life in children born between 2000 and 2011 in Scotland

“…Children born prematurely were found to be at increased risk of RSVH, including those born moderate-late preterm (33-35 wGA), where the incidence was more than double that in term children (4.6% vs. 1.9%, respectively; p < 0.0001). These data support the case for preventive strategies against severe RSV infection in preterm infants [22][23][24]. In addition to established high-risk comorbidities, such as CLD/BPD and CHD, our study provides valuable new data on the increased risk of RSVH in children with Down syndrome (RSVH incidence: 14.8%), cystic fibrosis (12.6%), cerebral palsy (15.5%), and neuromuscular disorders (17.0%), where published data are more scarce [25].…”

Hospital admissions and need for mechanical ventilation in children with respiratory syncytial virus before and during the COVID-19 pandemic: a Danish nationwide cohort study

“…Complications necessitating admission to intensive care units in children with RSV are typically respiratory failure due to severe bronchiolitis in young infants (aged <3 months) and children with comorbidities, such as prematurity, chronic lung diseases, congenital heart disease, and neuromuscular diseases. 11 , 12 , 13 , 14 Older infants and children without comorbidities are less likely to be admitted to an intensive care unit than infants aged younger than 3 months and those with comorbidities, and their complications are less well described. 15 Complications comprising severe bacterial infections, pneumothorax, neurological complications, and cardiac manifestations have primarily been reported in case series.…”

Risk Factors for Respiratory Syncytial Virus Infections in Moderate/Late Premature Infants in Turkey: A Prospective Multicenter Epidemiological Study

“…20,21 In a recent review, healthy premature infants 35 wGA were reported to be at higher risk for RSV infections compared with term infants. 22 After the restriction of the AAP guideline and Italian reimbursement system, a study from Italy reported higher number of RSV infections in preterm infants <36 wGA, especially in the presence of specific risk factors. 23 Similarly, an increase in RSV associated hospitalizations in 29 to 34 wGA preterm infants in the United States was reported after the change in AAP guideline.…”

“…28 For preterm infants !29 wGA, the chronological age of <3 months during RSV season was also reported as an important risk factor for severe RSV infections in several studies. [22][23][24] In recently published SENTINEL1 study including 1378 infants, the authors reported 82% of RSV hospitalizations within 60 days of birth hospital discharge among infants born during RSV season. 29 Similarly, the chronological age of being 3 months during RSV season was found to be an independent risk factor for RSV infections in our study.…”