Admission screening testing of patients and staff N95 masks are cost-effective in reducing COVID-19 hospital acquired infections.

BACKGROUND: COVID-19 outbreaks in acute care settings can have severe consequences for patients due to their underlying vulnerabilities, and can be costly due to additional patient bed days and the need to replace isolating staff. This study assessed the cost-effectiveness of clinical staff N95 masks and admission screening testing of patients to reduce COVID-19 hospital-acquired infections. METHODS: An agent-based model was calibrated to data on 178 outbreaks in acute care settings in Victoria, Australia between October 2021 and July 2023. Outbreaks were simulated under different combinations of staff masking (surgical, N95) and patient admission screening testing (none, RAT, PCR). For each scenario, average diagnoses, COVID-19 deaths, quality-adjusted life years (QALYs) from discharged patients, and costs (masks, testing, patient COVID-19 bed days, staff replacement costs while isolating) from acute COVID-19 were estimated over a 12-month period. FINDINGS: Compared to no admission screening testing and staff surgical masks, all scenarios were cost saving with health gains. Staff N95s + RAT admission screening of patients was the cheapest, saving A$78.4M [95%UI 44.4M-135.3M] and preventing 1,543 [1,070-2,146] deaths state-wide per annum. Both interventions were individually beneficial: staff N95s in isolation saved A$54.7M and 854 deaths state-wide per annum, while RAT admission screening of patients in isolation saved A$57.6M and 1,176 deaths state-wide per annum. INTERPRETATION: In acute care settings, staff N95 mask use and admission screening testing of patients can reduce hospital-acquired COVID-19 infections, COVID-19 deaths, and are cost-saving because of reduced patient bed days and staff replacement needs.

COVID-19 outbreaks in residential aged care facilities: an agent-based modeling study.

Introduction: A disproportionate number of COVID-19 deaths occur in Residential Aged Care Facilities (RACFs), where better evidence is needed to target COVID-19 interventions to prevent mortality. This study used an agent-based model to assess the role of community prevalence, vaccination strategies, and non-pharmaceutical interventions (NPIs) on COVID-19 outcomes in RACFs in Victoria, Australia. Methods: The model simulated outbreaks in RACFs over time, and was calibrated to distributions for outbreak size, outbreak duration, and case fatality rate in Victorian RACFs over 2022. The number of incursions to RACFs per day were estimated to fit total deaths and diagnoses over time and community prevalence.Total infections, diagnoses, and deaths in RACFs were estimated over July 2023-June 2024 under scenarios of different: community epidemic wave assumptions (magnitude and frequency); RACF vaccination strategies (6-monthly, 12-monthly, no further vaccines); additional non-pharmaceutical interventions (10, 25, 50% efficacy); and reduction in incursions (30% or 60%). Results: Total RACF outcomes were proportional to cumulative community infections and incursion rates, suggesting potential for strategic visitation/staff policies or community-based interventions to reduce deaths. Recency of vaccination when epidemic waves occurred was critical; compared with 6-monthly boosters, 12-monthly boosters had approximately 1.2 times more deaths and no further boosters had approximately 1.6 times more deaths over July 2023-June 2024. Additional NPIs, even with only 10-25% efficacy, could lead to a 13-31% reduction in deaths in RACFs. Conclusion: Future community epidemic wave patterns are unknown but will be major drivers of outcomes in RACFs. Maintaining high coverage of recent vaccination, minimizing incursions, and increasing NPIs can have a major impact on cumulative infections and deaths.