Epidemiology and pulmonary sequelae in infants with severe respiratory syncytial virus lower respiratory tract infection

Abstract

Respiratory Syncytial Virus (RSV) is the commonest cause of lower respiratory tract infection (LRTI) and hospitalization for LRTI in children. RSV LRTI during early childhood may increase susceptibility to recurrent wheezing and asthma. The objective of this study was to determine the pulmonary sequelae at one and two years of age following RSV LRTI hospitalization in term infants.

A longitudinal case-control study was undertaken in Johannesburg from April 2016 to December 2019. Cases constituted infants previously hospitalized with PCR-confirmed RSV LRTI; and controls were well infants not previously hospitalized with LRTI. A questionnaire detailing environmental and medical history, as well as a modified ISAAC questionnaire, was administered, and pulmonary function testing, including forced oscillation technique, tidal breath flow-volume loops, and multiple breath wash-out, was performed, at one and two years of age.

One (n=308) and two-year-old (n=214) cases were more likely than one (n=292) and two-yearold (n=209) controls to have experienced clinical pulmonary symptoms, including wheezing or whistling in the chest, received treatment for wheezing or whistling in the chest, and had any admissions for wheezing or whistling in the chest or any chest infection, after the initial RSV LRTI during infancy.

Pulmonary function testing reported that RSV LRTI during infancy led to an increase in airway resistance by two years, along with a decrease in compliance at both one and two years. There was an increased work of breathing at one year, but this was no longer present at two years. The expiratory time was decreased, while the expiratory flow parameters, as well as the time to peak expiratory flow to total expiratory time ratio were increased. FRC and LCI were abnormal at one year but had returned to normal at two years.

This study described the first set of pulmonary function indices in healthy one and two-year-old black African children from a LMIC.

Children hospitalized with RSV LRTI during infancy had more clinical and pulmonary function sequelae through to two years of age when compared to healthy controls. Whether prevention of RSV LRTI during early infancy would reduce the risk for subsequent pulmonary sequelae warrants further investigation.