Clinical relevance of viral codetection in infants with respiratory syncytial virus bronchiolitis.

Introduction: Respiratory syncytial virus (RSV) is the main cause of severe bronchiolitis, especially in infants. The aim of this study is to assess whether codetection of RSV and other respiratory viruses could affect the severity of this infection comparing with unique RSV detection.

Methods: A prospective study from 2016 to 2019 including children under 2 years who were admitted in the Emergency Service of the Hospital Universitari Arnau de Vilanova de Lleida (Spain) was performed. Nasopharyngeal samples from all patients were sent to the laboratory for RSV real-time PCR detection (GeneXpert®). A multiplex PCR that detects other respiratory viruses was done in all RSV-positive samples. Patients'medical records were checked to collect clinical data (hospital length of stay, BROSJOD score, ICU admission, need for ventilatory support or transfer to a reference hospital). Patients were divided in two groups: infants with unique RSV detection and infants with viral codetection. Bivariant analyses were performed to analyze the data obtained.

Results: During the period of study 437 RSV bronchiolitis were diagnosed. In 199 of them (177/437; 45,5%) another respiratory virus was detected concomitantly. Bivariant analyses do not show statistically significant differences between both groups.

Conclusions: Viral codetection in infants with RSV bronchiolitis is frequent. However, it does not seems to affect the severity of this infection.