(335) Co-Infection Association With Severity of Infection in Hospitalized RSV Positive Pediatric Patients

Introduction: RSV is the leading cause of hospitalization in children less than 1 year of age. 2 - 3% of young infants with RSV infection are hospitalized annually per CDC. Well-known factors associated with morbidity include prematurity, cyanotic congenital heart disease, chronic lung disease of prematurity, and tobacco smoke exposure. There are few reports, with conflicting findings, on the association of co-infections with RSV disease severity. We hypothesize that there is increased illness severity in hospitalized RSV patients who are co-infected with other pathogens.

Methods: A retrospective review of the electronic medical records of patients younger than 6 years with RSV respiratory infection between October 2017 and March 2021 was conducted at a single institution in the southeastern United States. Patients were identified through ICD-10 codes. Demographic data, length of stay, respiratory support (RS), antibiotic use, and identified co-infections were collected. RS was used as an indicator of disease severity and was defined as use of heated, humidified, high flow nasal cannula, non-invasive mechanical ventilator or invasive mechanical ventilator.

Results: Of the 458 patient visits identified, 86 (19%) required RS. The median age of patients requiring RS was 7 months vs 12 months for those not requiring RS (p < 0.001). There was confirmed co-infection, either by culture, antigen or PCR testing, in 31 of 372 (8%) of patient not requiring RS vs 21 of 86 (24%) of patient requiring RS (odds ratio: 3.55; 95% CI: 1.92, 6.57; p < 0.001). Patients requiring RS were more likely to have bacterial compared to viral co-infections identified (11 viruses, 15 bacteria ) compared to those that did not require RS (31 viruses, 7 bacteria; p = 0.001). Fifty-five percent of patients needing RS versus 19% of patients not needing RS received antibiotic therapy (p < 0.001). Also, patients needing RS had a median hospital stay of 8 days versus median of 2 days in patient not requiring RS (p < 0.001).

Conclusions: There is a statistically significant 3.6 times increase in odds of requiring RS, an indicator of disease severity, if co-infection is present in patients with RSV. Bacterial co-infections appear to be associated with a greater need for RS than viral infections.