Seroprevalence of SARS-CoV-2 antibodies among homeless people living rough, in shelters and squats: A large population-based study in France

Abstract

Background Overcrowded housing, as well as inadequate sanitary conditions, contribute to making homeless people particularly vulnerable to the SARS-CoV-2 infection. We aimed to assess the seroprevalence of the SARS-CoV-2 infection among people experiencing homelessness on a large city-wide scale in Marseille, France, taking into account different types of accommodation. Methods A consortium of outreach teams in 48 different locations including streets, slums, squats, emergency or transitional shelters and drop-in centres participated in the inclusion process. All participants consented to have a validated rapid antibody assay for immunoglobulins M (IgM) and G (IgG) and to answer a questionnaire on medical health conditions, comorbidities, and previous COVID-19 symptoms. Information on their housing conditions since the COVID-19 crisis was also collected from the participants. Results From June 01 to August 05, 2020, 1,156 homeless participants were enrolled in the study and tested. The overall seroprevalence of SARS-CoV-2 IgG/IgM antibodies was 5.6% (95%CI 2.3–7.0), ranging from 2.2% in people living on the streets to 8.1% in people living in emergency shelters (P = 0.009). Around one third of the seropositive participants reported COVID-19 symptoms. Compared to the general population in Marseille (3.6%), the homeless population living in the same urban area experienced a significantly increased risk of SARS-CoV-2 infection (|z| = 3.65 > 1.96). Conclusion These findings highlight the need for regular screening among the homeless to prevent clustering in overcrowded or inadequate accommodations. It is also necessary to provide essential resources to keep homeless people healthy, the vast majority of whom have cumulative risk factors for SARS-CoV-2 infection.

A Scoping Review of the Health Impact of the COVID-19 Pandemic on Persons Experiencing Homelessness in North America and Europe

“…A number of included studies reported infection attack rates of SARS-CoV-2 among study participants: 29 studies measured positivity rates (i.e., current infection) [ 13 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 ], seven measured seroprevalence (i.e., prevalence of antibodies for SARS-CoV-2, indicating historic infection) [ 61 , 62 , 63 , 64 , 65 , 66 , 67 ], and four measured both positivity and seroprevalence rates [ 68 , 69 , 70 , 71 ]. Additionally, data regarding SARS-CoV-2 symptoms reported by study participants were provided by 32 articles [ 7 , 8 , 33 , 34 , 35 , 36 , 38 , 42 , 45 , 46 , …”

“…Similarly, Ghinai et al [ 48 ] reported that increased numbers of private bathrooms were associated with lower prevalence rates. Living in a congregate or crowded setting [ 61 ] and shared sleeping arrangements [ 48 ] were also identified as risk factors. In addition, a study by Roland et al [ 69 ] reported that persons who shared a room with someone who tested positive, or did not know, were significantly more likely to test positive.…”

“…Additional risk factors were identified by several studies. Two studies found the presence of symptoms to be associated with testing positive for SARS-CoV-2 [ 47 , 61 ], while four studies found no statistical significance between symptoms of persons testing positive and negative [ 33 , 38 , 46 , 69 ]. Two studies reported a relationship between older age and increased likelihood of testing positive among PEH [ 38 , 48 ], though this relationship was not statistically significant in the study by Kiran et al [ 38 ], and after adjusting for individual level factors and clustering at shelters, positivity rates no longer differed significantly by age in the study by Ghinai et al [ 48 ].…”

Social Sciences and Social Justice in the Design, Implementation and Evaluation of Measures Against COVID-19 - the Case Study of France in 2020

“…Further, higher exposure risk is found in multi-person households, in non-European immigrant populations and in persons aged between 30-49 years irrespective of living conditions, with almost double the COVID-19 seroprevalence in priority city areas (Quartier Prioritaire de Politique de la Ville -QPV), which represent poverty-concentrated territories (Warszawski et al, 2020). In Marseille, the homeless population living in the same urban area as the general population demonstrated a significantly increased risk of infection (Loubiere et al, 2021). Economic studies which contain the mapping of populations living under precarious conditions in Paris demonstrate the higher risk and vulnerability of households in precarious territorial units that are typically characterized by being overcrowded, large, with many youths facing economic uncertainty and low education levels (Goutte et al, 2020).…”

Residential Mobility of a Cohort of Homeless People in Times of Crisis: COVID-19 Pandemic in a European Metropolis

“…The consequences of this crisis are also economic and social, particularly affecting the most vulnerable people [ 3 , 15 ]. Studies have shown that homeless people are at a greater risk of SARS-CoV-2 infection than the general population [ 16 , 17 ]. Homeless people have suffered from the disruption of their living and collecting places due to the epidemic.…”