Screening of SARS-CoV-2 among homeless people, asylum-seekers and other people living in precarious conditions in Marseille, France, March-April 2020

Background: Surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among sheltered homeless and other vulnerable people might provide the information needed to prevent its spread within accommodation centres. Methods: Data were obtained from 698 participants in different accommodation centres (411 homeless individuals, 77 asylum-seekers, 58 other people living in precarious conditions and 152 employees working in these accommodation centres) who completed questionnaires and had nasal samples collected between 26 March and 17 April 2020. SARS-CoV-2 carriage was assessed by quantitative PCR. Results: We found a high acceptance rate (78.9%) for testing. Overall, 49 people (7.0%) were positive for SARS-CoV-2, including 37 homeless individuals (of 411, 9.0%) and 12 employees (of 152, 7.9%). SARS-CoV-2 positivity correlated with symptoms, although 51% of patients who tested positive did not report respiratory symptoms or fever. Among homeless people, being young (18-34 years) (odds ratio 3.83, 95% confidence interval 1.47-10.0, p = 0.006) and being housed in one specific shelter (odds ratio 9.13, 95% confidence interval 4.09-20.37, p < 0.001) were independent factors associated with SARS-CoV-2 positivity (rates of 11.4% and 20.6%, respectively). Discussion: Symptom screening alone is insufficient to prevent SARS-CoV-2 transmission in vulnerable sheltered people. Systematic testing should be promoted. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases.

Automated summary

Surveillance of SARS-CoV-2 infection among sheltered homeless and vulnerable populations found a high positivity rate, with symptom screening alone deemed insufficient to prevent virus transmission. Systematic testing should be promoted to mitigate spread within accommodation centers.