(P-203) Systematic Literature Review (SLR) of Respiratory Syncytial Virus (RSV) Burden and Health Care Utilization (HCU) Among Infants in the United States (US)

Background: RSV is the leading cause of lower respiratory tract infections (LRTI) and hospitalizations in US infants.

Objectives: A SLR following PRISMA guidelines was conducted to determine recent (2015-2020) RSV burden and HCU among US infants in the inpatient (IP), emergency department (ED), outpatient (OP), and urgent care (UC) settings.

Methods: Literature searches were conducted in PubMed, Embase, and WoS databases in Jan 2020. US studies with RSV and medically-attended (MA) RSV LRTI infections published from 1969-Jan 2020 were eligible. Outcomes included RSV incidence proportion, IP hospitalizations and ED, OP, and UC visits. The Newcastle-Ottawa Scale (NOS), which assesses three quality parameters (selection, comparability, and exposure/outcome) consisting of 8 items, was used to evaluate study quality. Each item is scored one point, except for comparability, which can score up to two points. A study is deemed good quality if it scores 3 or 4 in the selection domain and 1 or 2 in the comparability domain, and 2 or 3 in the exposure/outcome domain. Fair quality studies score a 2 in selection, 1 or 2 in comparability, and 2 or 3 in exposure/outcome. Poor quality studies score a 0 or 1 in each domain.

Results: 5,456 unique articles were identified and reviewed for title and abstract. Of these, 1,180 full-text were reviewed; 410 were eligible for abstraction leading to 45 studies with unique 2015-2020 RSV data. Among these, 26 had data for infants and 9 presented MA RSV LRTI data. Six were good quality studies, 11 were fair, and 9 were poor as assessed by NOS. Most (n=25, 96%) presented IP data. No study had data for UC; only 2 studies presented data for ED, and 1 for OP. Data specific to full-term infants were only reported in 2 NOS fair quality studies. Focusing on the 6 NOS good quality studies, notable variations were seen in RSV incidence proportion (n=5, 5.2% to 37.6%), RSV hospitalization proportion (n=2, 14% to 75%), and ICU admission proportion (n=3, 29% to 58%) due to differences in study populations. No data were available on RSV hospitalization rate or length of stay. There were no HCU data describing the patient journey across settings. Systematic laboratory testing for RSV was not seen in any study.

Conclusions: This review highlights gaps in our understanding of the RSV burden in US infants across healthcare settings, particularly for the ED, OP, and UC settings and for full-term infants. High quality studies with systematic primary data generation for RSV and RSV LRTI are critically needed for elucidating all infants' patient journeys and illustrating the long-term impact of RSV.