ABSTRACT
ImportanceApproximately 356,000 people stay in homeless shelters nightly in the US. These individuals are at high risk for COVID-19. ObjectiveTo assess clinical outcomes, costs, and cost-effectiveness of strategies for COVID-19 prevention and management among sheltered homeless adults. DesignWe developed a dynamic microsimulation model of COVID-19. We modeled sheltered homeless adults in Boston, Massachusetts, using cohort characteristics and costs from Boston Health Care for the Homeless Program. Disease progression, transmission, and clinical outcomes data were from published literature and national databases. We examined surging, growing, and slowing epidemics (effective reproduction numbers [Re] 2.6, 1.3, and 0.9). Costs were from a health care sector perspective; time horizon was 4 months. Setting & ParticipantsSimulated cohort of 2,258 adults residing in homeless shelters in Boston. InterventionsWe assessed combinations of daily symptom screening with same-day polymerase chain reaction (PCR) testing of screen-positive individuals, universal PCR testing every 2 weeks, hospital-based COVID-19 care, alternate care sites [ACSs] for mild/moderate COVID-19 management, and moving people from shelters to temporary housing, compared to no intervention. Main OutcomesInfections, hospital-days, costs, and cost-effectiveness. ResultsCompared to no intervention, daily symptom screening with ACSs for those with pending tests or confirmed COVID-19 and mild/moderate disease leads to 37% fewer infections and 46% lower costs when Re=2.6, 75% fewer infections and 72% lower costs when Re=1.3, and 51% fewer infections and 51% lower costs when Re=0.9. Adding universal PCR testing every 2 weeks further decreases infections in all epidemic scenarios, with incremental cost per case prevented of $1,000 (Re=2.6), $27,000 (Re=1.3), and $71,000 (Re=0.9). In all scenarios, moving shelter residents to temporary housing with universal PCR testing every 2 weeks is most effective but substantially more costly than other options. Results are most sensitive to the cost and sensitivity of PCR testing and the efficacy of ACSs in preventing transmission. Conclusions & RelevanceDaily symptom screening and ACSs for sheltered homeless adults will substantially decrease COVID-19 cases and reduce costs compared to no intervention. In a surging epidemic, adding universal PCR testing every 2 weeks further decreases cases at modest incremental cost and should be considered. Key PointsO_ST_ABSQuestionC_ST_ABSWhat are the projected clinical outcomes and costs of strategies for reducing COVID-19 infections among people experiencing sheltered homelessness? FindingsIn this microsimulation modeling study, daily symptom screening with polymerase chain reaction (PCR) testing of screen-positive individuals, paired with non-hospital care site management of people with mild to moderate COVID-19, substantially reduces infections and lowers costs over 4 months compared to no intervention, across a wide range of epidemic scenarios. In a surging epidemic, adding periodic universal PCR testing to symptom screening and non-hospital care site management improves clinical outcomes at modestly increased costs. Periodic universal PCR testing paired with temporary housing further reduces infections but at much higher cost. MeaningDaily symptom screening with PCR testing of screen-positive individuals and use of alternate care sites for COVID-19 management among sheltered homeless people will substantially prevent new cases and reduce costs compared to other strategies.
