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We analyzed the baseline wave of \u201cGesundheit 65+\u201d, a German nationwide population-registry survey. This wave was performed between June 2021 and April 2022, with a sample of 3450 participants aged 65 to 100 living in private households. SARS-CoV-2 infection prevalence was 3.5% (95% confidence interval, CI 2.6\u20134.5), slightly higher among those aged 85+, and higher among those receiving home care, and not having double vaccination. We identified with multivariable logistic regression that not having double vaccination (odds ratio, OR\u2009=\u20099.72; CI 4.81\u201319.61), receiving in-person visits (OR\u2009=\u20092.96; CI 1.12\u20137.80), and not living alone (OR\u2009=\u20091.96; CI 1.02\u20133.76) were independently associated with SARS-CoV-2 infection, but receiving formal or informal care at home, and participating in work and social activities were not. Our results emphasize the importance of vaccination and caution during in-person interactions. Despite receiving formal or informal care at home implying close personal contact, we did not detect increased infection risk in those receiving care at home.<\/jats:p>","DOI":"10.1038\/s41598-026-37108-7","type":"journal-article","created":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T04:46:20Z","timestamp":1770007580000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Nationwide cross-sectional study results on long-term care and SARS-CoV-2 infection among older adults in Germany during the COVID-19 pandemic"],"prefix":"10.1038","volume":"16","author":[{"given":"Ana Magdalena","family":"Ordonez-Cruickshank","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hannelore","family":"Neuhauser","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arina","family":"Zanuzdana","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christina","family":"Poethko-M\u00fcller","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Beate","family":"Gaertner","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Judith","family":"Fuchs","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,2,2]]},"reference":[{"key":"37108_CR1","unstructured":"WHO Regional Office for Europe. 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