SARS-CoV-2 Prevalence, Transmission, Health-Related Outcomes and Control Strategies in Homeless Shelters: Systematic Review and Meta-Analysis

Background: People experiencing homelessness (PEH) may be at particular risk for COVID19. We synthesised the evidence on SARS-Cov-2 infection, transmission, outcomes of disease, effects of non-pharmaceutical interventions (NPI), and the effectiveness of targeted strategies for infection prevention and control (IPC). Methods: Systematic review of articles, reports and grey-literature indexed in electronic databases (EMBASE, WHO-Covid19, Web of Science), pre-print repositories, institutional websites, and handsearching. Empirical papers of any study design addressing Covid-19 in PEH or homeless shelters’ staff in English were included. (PROSPERO 2020 CRD42020187033) Findings: Of 194 publications, 13 studies were included (two modelling, ten observational and one qualitative study). All were conducted in high-income countries. Random-effect meta-analysis of prevalence estimates yields a baseline SARS-Cov-2 prevalence of 2·14% (95% Confidence-Interval, 95%CI=1·02-3·27) in PEH and 1·72% (95%CI=0·31-3·12) in staff. In outbreaks, the pooled prevalence increases to 29·49% (95%CI=16·44-29·55) in PEH and 15·18% (95%CI=8·95-21·42) in staff. Main IPC strategies were universal and rapid testing, expansion of non-congregate housing support, and individual measures in shelters (bed spacing, limited staff rotation). Interpretation: Up to 30% PEH and 17% staff are infected during outbreaks of SARS-Cov-2 in homeless shelters. Most studies were conducted in the USA. No studies were found on health-related outcomes or health effects of NPI. An overview and evaluation of IPC strategies for PEH, including a better understanding of disease transmission, and reliable data on PEH within Covid-19 notification systems is needed. Qualitative studies may serve to voice PEH experiences and guide future evaluations and IPC strategies. Funding: No source of funding. Declaration of Interests: The review has been conducted in the scope of the German Competence Net Public Health Covid-19. JS is volunteering (without financial compensation) for a German NGO which provides medical services free of charge for - among others - individuals living in homeless shelters. He further reports membership of the German social democratic party (SPD). The other authors state that they have no competing interests.