Neighbourhood-level burden of social risk factors on respiratory syncytial virus hospitalization in Ontario, Canada, 2016-2019

Introduction: Beyond clinical risk factors, little is known about the impact of social determinants on respiratory syncytial virus (RSV) burden. Our study aimed to estimate RSV-related hospitalization rates across sociodemographic and housing characteristics. Methods: We conducted a population-based study of all RSV-related hospitalizations in Ontario, Canada between September 1, 2016 and August 31, 2019 using validated hospital discharge codes and census data. Crude and age-standardized annualized RSV incidence rates and rate ratios (RR) were estimated for a range of individual-level demographics and neighbourhood-level measures of marginalization and housing characteristics. Results: Overall, the annual RSV-related hospitalization rate was 27 per 100,000, with the highest rates observed in children <12 months (1049 per 100,000) and 12-23 months (294 per 100,000), and adults ≥85 years (155 per 100,000). Higher RSV-related hospitalization rates were associated with increasing marginalization quintile (Q) of material resources (RR: 1.4; Q5: 33 per 100,000 versus Q1: 24 per 100,000) and household instability (RR: 1.5; Q5: 31 per 100,000 versus Q1: 22 per 100,000). Conclusion: The burden of RSV-related hospitalization was greatest in young children and older adults, with variation by sociodemographic and housing factors. Understanding the role of these social factors is crucial for informing equitable preventive program delivery. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was supported by a SickKids-Canadian Institutes of Health Research New Investigator Grant in Child and Youth Health (NI19-1065) and Public Health Ontario. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: We obtained ethical approval from the Public Health Ontario Research Ethics Board. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Public Health Ontario cannot disclose underlying data. Information on the data request process is available at https://www.publichealthontario.ca/en/data-and-analysis/using-data/data-requests