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

Abstract

BackgroundPeople 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). MethodsSystematic 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) FindingsOf 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{middle dot}14% (95% Confidence-Interval, 95%CI=1{middle dot}02-3{middle dot}27) in PEH and 1{middle dot}72 % (95%CI=0{middle dot}31-3{middle dot}12) in staff. In outbreaks, the pooled prevalence increases to 29{middle dot}49% (95%CI=16{middle dot}44-29{middle dot}55) in PEH and 15{middle dot}18% (95%CI=8{middle dot}95-21{middle dot}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). InterpretationUp 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. FundingNo source of funding. Panel 1: Research in contextO_ST_ABSEvidence before this studyC_ST_ABSPeople experiencing homelessness (PEH) are at increased risk of infectious, chronic, and mental health adverse conditions. Due to the risk of transmission in shared accommodations, PEH may be particularly vulnerable to SARS-Cov-2 infection and worse clinical outcomes. Non-pharmaceutical interventions (NPIs) taken to mitigate the SARS-Cov-2 outbreak may have further aggravated health and social conditions. However, there is no evidence synthesis on the SARS-Cov-2 epidemiology among PEH, the correspondent clinical and other health-related outcomes as well as health effects of NPIs on these groups. Added value of this study We reviewed and synthesized existent evidence on the risk of infection and transmission, risk of severe course of disease, effect of NPIs on health outcomes and the effectiveness of implemented measures to avert risks and negative outcomes among PEH. Results of the identified studies suggest that both PEH and shelter staff are at high risk of SARS-Cov-2 infection, especially in case of a local outbreak. Due to the low prevalence of symptoms at the time of a positive SARS-Cov-2 test among PEH, symptom screening alone may not be efficient to control outbreaks. Instead, universal and rapid testing conjugated with expansion of non-congregate housing support, and individual measures in shelters, are discussed as sensible strategies. Implications of all the available evidence A comprehensive overview of NPIs and shelter strategies targeting PEH and evaluation of their effectiveness and unintended health consequences is needed. Qualitative research considering living realities of PEH can facilitate understanding of their specific needs during the pandemic.