Environmental contamination with SARS-CoV-2 in nursing homes

• Published in: Journal of the American Geriatrics Society 2022-01, Vol.70 (1), p.29-39
• Main Authors: Mody, Lona, Gibson, Kristen E, Mantey, Julia, Bautista, Liza, Montoya, Ana, Neeb, Karen, Jenq, Grace, Mills, John P, Min, Lillian, Kabeto, Mohammed, Galecki, Andrzej, Cassone, Marco, Martin, Emily T
• Format: Article
• Language: English
• Subjects: Activities of daily living; Aged; Aged, 80 and over; Clinical Investigation; Congestive heart failure; Contamination; Coronaviruses; COVID-19; COVID-19 - prevention & control; COVID-19 - therapy; COVID‐19‐Related Content; Decontamination; Dementia disorders; Diabetes mellitus; Environmental Pollution - adverse effects; Female; Humans; Infection Control; Male; Michigan; Nursing Homes; Patients; Population studies; Prospective Studies; Risk factors; RNA, Viral - analysis; SARS-CoV-2 - isolation & purification; Severe acute respiratory syndrome coronavirus 2
• ISSN: 0002-8614; 1532-5415; 1532-5415
• DOI: 10.1111/jgs.17531

SARS-CoV-2 outbreaks in nursing homes (NHs) have been devastating and have led to the creation of coronavirus disease 2019 (COVID-19) units within NHs to care for affected patients. Frequency and persistence of SARS-CoV-2 environmental contamination in these units have not been studied. A prospective cohort study was conducted between October 2020 and January 2021 in four Michigan NHs. Swabs from high-touch surfaces in COVID-19-infected patient rooms were obtained at enrollment and follow-up. Demographic and clinical data were collected from clinical records. Primary outcome of interest was the probability of SARS-CoV-2 RNA detection from specific environmental surfaces in COVID-19 patient rooms. We used multivariable logistic regression to assess patient risk factors for SARS-CoV-2 contamination. Pairwise Phi coefficients were calculated to measure correlation of site-specific environmental detection upon enrollment and during follow-up. One hundred and four patients with COVID-19 were enrolled (61.5% >80 years; 67.3% female; 89.4% non-Hispanic White; 51% short stay) and followed up for 241 visits. The study population had significant disabilities in activities of daily living (ADL; 81.7% dependent in four or more ADLs) and comorbidities, including dementia (55.8%), diabetes (40.4%), and heart failure (32.7%). Over the 3-month study period, 2087 swab specimens were collected (1896 COVID-19 patient rooms, 191 common areas). SARS-CoV-2 positivity was 28.4% (538/1896 swabs) on patient room surfaces and 3.7% (7/191 swabs) on common area surfaces. Nearly 90% (93/104) of patients had SARS-CoV-2 contamination in their room at least once. Environmental contamination upon enrollment correlated with contamination of the same site during follow-up. Functional independence increased the odds of proximate contamination. Environmental detection of viral RNA from surfaces in the rooms of COVID-19 patients is nearly universal and persistent; more investigation is needed to determine the implications of this for infectiousness. Patients with greater independence are more likely than fully dependent patients to contaminate their immediate environment.