{"id":23350,"date":"2026-03-04T09:25:56","date_gmt":"2026-03-04T14:25:56","guid":{"rendered":"https:\/\/www.ices.on.ca\/?post_type=journal_article&#038;p=23350"},"modified":"2026-03-05T09:31:57","modified_gmt":"2026-03-05T14:31:57","slug":"acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness","status":"publish","type":"journal_article","link":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/","title":{"rendered":"Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study"},"content":{"rendered":"<p><strong>Background<\/strong> \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute healthcare utilization following infection. We quantified acute healthcare utilization associated with robustly measured SARS-CoV-2 infection or reinfection among people experiencing homelessness.<\/p>\n<p><strong>Methods<\/strong> \u2014 In this prospective cohort study, we recruited randomly selected individuals experiencing homelessness in Toronto, Canada in summer 2021. Over one year of follow up, participants completed detailed surveys and provided biological samples to test for SARS-CoV-2 infection (RT-PCR and ELISA). Research data were linked to health administrative databases held at ICES, a health administrative data repository. Outcomes were identified using ICD-10 codes and temporal proximity to infection onset, and participants with confirmed infection were compared to participants without infection history.<\/p>\n<p><strong>Results<\/strong> \u2014 Two thirds of participants (n\u2009=\u2009640) experienced at least one SARS-CoV-2 infection over the observation period; 25% experienced two or more infections. Prior to Omicron dominating infections, coding identified 1.55 (95% CI 1.0\u20132.5) hospitalizations and 4.39 (3.9\u20135.9) emergency department visits per 100 person-years; within 30 days of infection onset, rates were 4.07 (95% CI 2.9\u20135.6) and 13.69 (95% CI 11.4\u201316.4), respectively. Hospitalization and emergency department rates were 16.8 and 2.4 times higher than during random 30-day periods without infection. After Omicron variants became dominant, coding identified 2.27 (95% CI 1.1\u20134.5) hospitalizations and 3.97 (95% CI 2.4\u20136.7) emergency department visits per 100 person-years; within 30 days of infection, rates were 1.29 (95% CI 0.3\u20133.3) hospitalizations and 5.8 (95% CI 3.6\u20139.0) emergency department visits per 100-person years. However, post-Omicron rates within 30 days of infection were not significantly higher than for 30-day periods without infection.<\/p>\n<p><strong>Conclusions<\/strong> \u2014 Despite extremely high SARS-CoV-2 infection and reinfection rates, people experiencing homelessness in Toronto had relatively low rates of acute healthcare utilization following infection. Future work is needed to ascertain rates of chronic outcomes, like post-COVID condition.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute healthcare utilization following infection. We quantified acute healthcare utilization associated with robustly measured SARS-CoV-2 infection or reinfection among people experiencing homelessness. Methods \u2014 In this prospective cohort study, we recruited randomly selected individuals experiencing homelessness in Toronto, Canada in [&hellip;]<\/p>\n","protected":false},"template":"","migration-helper-automated":[],"migration-manual":[],"topic":[62,19,35],"migration-helper-qa-sample-set":[],"class_list":["post-23350","journal_article","type-journal_article","status-publish","hentry","topic-health-services-research","topic-marginalized-populations","topic-public-health"],"acf":{"citation":"Richard L, Carter B, Liu M, Nisenbaum R, Hwang SW. <em>PLoS One<\/em>. 2026; 21(3): e0343639.","source_url":"https:\/\/doi.org\/10.1371\/journal.pone.0343639","ices_scientist":[1271],"site":[6739],"research_program":[6745],"news_release":"","journal_article":"","atlas":"","research_report":"","infographic":"","video":"","downloads":null,"links":null,"sitecore_item_id":"","sitecore_item_name":"","sitecore_field_values":"","previous_url":""},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.2 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>ICES | Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study<\/title>\n<meta name=\"description\" content=\"Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"ICES | Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study\" \/>\n<meta property=\"og:description\" content=\"Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/\" \/>\n<meta property=\"og:site_name\" content=\"ICES\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/ICESOntario\/\" \/>\n<meta property=\"article:modified_time\" content=\"2026-03-05T14:31:57+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2024\/11\/ic-es-data-discovery-better-health-logo.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"675\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\\\/\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\\\/\",\"name\":\"ICES | Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#website\"},\"datePublished\":\"2026-03-04T14:25:56+00:00\",\"dateModified\":\"2026-03-05T14:31:57+00:00\",\"description\":\"Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\\\/#breadcrumb\"},\"inLanguage\":\"fr-FR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Journal Articles\",\"item\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/publications\\\/journal-articles\\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#website\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/\",\"name\":\"ICES\",\"description\":\"POPULATION-BASED HEALTH RESEARCH THAT MAKES A DIFFERENCE\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#organization\"},\"alternateName\":\"Institute for Clinical Evaluative Sciences\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"fr-FR\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#organization\",\"name\":\"ICES\",\"alternateName\":\"Institute for Clinical Evaluative Sciences\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/www.ices.on.ca\\\/wp-content\\\/uploads\\\/2023\\\/04\\\/ices-logo.png\",\"contentUrl\":\"https:\\\/\\\/www.ices.on.ca\\\/wp-content\\\/uploads\\\/2023\\\/04\\\/ices-logo.png\",\"width\":\"676\",\"height\":\"618\",\"caption\":\"ICES\"},\"image\":{\"@id\":\"https:\\\/\\\/www.ices.on.ca\\\/fr\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/ICESOntario\\\/\",\"https:\\\/\\\/www.linkedin.com\\\/company\\\/ices-research-institute\\\/\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"ICES | Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study","description":"Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/","og_locale":"fr_FR","og_type":"article","og_title":"ICES | Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study","og_description":"Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute","og_url":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/","og_site_name":"ICES","article_publisher":"https:\/\/www.facebook.com\/ICESOntario\/","article_modified_time":"2026-03-05T14:31:57+00:00","og_image":[{"width":1200,"height":675,"url":"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2024\/11\/ic-es-data-discovery-better-health-logo.jpg","type":"image\/jpeg"}],"twitter_card":"summary_large_image","schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/","url":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/","name":"ICES | Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study","isPartOf":{"@id":"https:\/\/www.ices.on.ca\/fr\/#website"},"datePublished":"2026-03-04T14:25:56+00:00","dateModified":"2026-03-05T14:31:57+00:00","description":"Background \u2014 Current literature drastically underestimates SARS-CoV-2 infection among homeless populations, undermining our understanding of acute","breadcrumb":{"@id":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/#breadcrumb"},"inLanguage":"fr-FR","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/acute-healthcare-utilization-associated-with-positive-sars-cov-2-testing-or-serology-among-people-experiencing-homelessness\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.ices.on.ca\/fr\/"},{"@type":"ListItem","position":2,"name":"Journal Articles","item":"https:\/\/www.ices.on.ca\/fr\/publications\/journal-articles\/"},{"@type":"ListItem","position":3,"name":"Acute healthcare utilization associated with positive SARS-CoV-2 testing or serology among people experiencing homelessness: a prospective cohort study"}]},{"@type":"WebSite","@id":"https:\/\/www.ices.on.ca\/fr\/#website","url":"https:\/\/www.ices.on.ca\/fr\/","name":"ICES","description":"POPULATION-BASED HEALTH RESEARCH THAT MAKES A DIFFERENCE","publisher":{"@id":"https:\/\/www.ices.on.ca\/fr\/#organization"},"alternateName":"Institute for Clinical Evaluative Sciences","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.ices.on.ca\/fr\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"fr-FR"},{"@type":"Organization","@id":"https:\/\/www.ices.on.ca\/fr\/#organization","name":"ICES","alternateName":"Institute for Clinical Evaluative Sciences","url":"https:\/\/www.ices.on.ca\/fr\/","logo":{"@type":"ImageObject","inLanguage":"fr-FR","@id":"https:\/\/www.ices.on.ca\/fr\/#\/schema\/logo\/image\/","url":"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2023\/04\/ices-logo.png","contentUrl":"https:\/\/www.ices.on.ca\/wp-content\/uploads\/2023\/04\/ices-logo.png","width":"676","height":"618","caption":"ICES"},"image":{"@id":"https:\/\/www.ices.on.ca\/fr\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/ICESOntario\/","https:\/\/www.linkedin.com\/company\/ices-research-institute\/"]}]}},"_links":{"self":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/journal_article\/23350","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/journal_article"}],"about":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/types\/journal_article"}],"acf:post":[{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/research_program\/6745"},{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/site\/6739"},{"embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/ices_scientist\/1271"}],"wp:attachment":[{"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/media?parent=23350"}],"wp:term":[{"taxonomy":"migration-helper-automated","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/migration-helper-automated?post=23350"},{"taxonomy":"migration-manual","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/migration-manual?post=23350"},{"taxonomy":"topic","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/topic?post=23350"},{"taxonomy":"migration-helper-qa-sample-set","embeddable":true,"href":"https:\/\/www.ices.on.ca\/fr\/wp-json\/wp\/v2\/migration-helper-qa-sample-set?post=23350"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}