Keeping Older Persons in Aged Care Safe From Vaccine Adverse Events: The COVIRAC Project

Introduction: Older persons cared for in residential aged care facilities (RACF) are a priority group to be protected against Influenza and respiratory syncytial virus (RSV) through vaccination. Given their frailty and/or co-morbidities, undertaking clinical trials in this population is rarely feasible. [1] This restricts understanding the safety profile of vaccines in this vulnerable population until after program implementation. In Australia, conventional surveillance of adverse events following immunisation (AEFI) encompasses spontaneous surveillance through direct reporting to jurisdiction-level health departments or the national regulator, and active surveillance through solicited electronic surveys sent by SMS or email. However, with staffing limitations minimising spontaneous reporting and the gap in technology literacy on the part of all most notably residents to complete online questionnaires, these surveillance systems are unlikely to provide clear insight into the vaccine safety profile in RACF. COVIRAC is an automated digital solution project designed to enhance the monitoring of AEFI in RACF by utilising electronic health records (EHR) routinely created by the facility. Aims: To describe the safety of priority vaccines (such as Influenza and RSV vaccines) in RACF residents, and improve vaccine policy decision making and community vaccine confidence through timely provision of a vaccine safety evidence base. Methods: COVIRAC will employ a self-controlled case series approach to assess AEFI for Influenza and RSV vaccines. The team will have access to de-identified EHR data provided by a commercial RACF EHR database software provider. The frequency of clinical events (including medical visits, hospital transfers, falls, and deaths) in the risk window following each vaccination will be compared with control periods for the same resident. The analysis period will span up to 11 weeks prior to vaccination as a control window (with a 2-week washout to account for "healthy vaccinee effect" [2]) and up to 17 weeks post-vaccination. These data will assist in determining the incidence rate and incidence rate ratio of all AEFI and specific reactions of interest. Results: The findings from this project will provide an evidence-base (along with recommendations) for policy makers to modify current vaccination programs, or tailor new programs with protecting RACF residents from AEFI. These findings will also assist older persons in RACF and the community with