ABSTRACT
Background The COVID-19 pandemic has disproportionately affected nursing home (NH) patients, accounting for 5% of all cases and 32% of all COVID-19 deaths nationwide. Little is known about the frequency and persistence of SARS-CoV-2 environmental contamination in NHs. We characterize SARS-CoV-2 contamination in the rooms of COVID-19 patients and common areas in and around COVID-19 units. Methods A prospective cohort study was conducted at four NHs in Michigan between October 2020 and January 2021. Clinical research personnel obtained swab specimens from high-touch room surfaces of COVID-19 infected patients, up to three times per patient. Weekly swab specimens from six high-touch surfaces in common areas were also obtained. Demographic and clinical data were collected from patient clinical records. Our primary outcome of interest was the probability of SARS-CoV-2 detection from specific environmental surfaces in COVID-19 patient rooms. Results One hundred four patients with COVID-19 were enrolled and followed for 241 visits. Patient characteristics included: 61.5% over the age of 80;67.3% female;89.4% non-Hispanic white;50.1% short-stay. 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) (Table 1). Over the 3-month study period, 2087 swab specimens were collected (1896 COVID-19 patient room surfaces, 191 common area swabs). Figure 1 shows contamination rates at sites proximate and distant to the patient bed. SARS-CoV-2 positivity was 28.4% (538/1896 swabs) on patient room surfaces and 3.7% (7/191 swabs) on common area surfaces. Over the course of follow-up, 89.4% (93/104) of patients had SARS-CoV-2 contamination in their room at least once (Figure 2). Environmental contamination detected on enrollment correlated with contamination of the same site during follow-up. Functional independence increased the odds of proximate contamination. Table 1. Clinical and Demographic Characteristics of the Study Population Including Short- and Long-stay Patients Figure 1. Contamination of Environmental Surfaces Relative to Distance from Patient Bed Figure 2. SARS-CoV-2 on Swab Specimens Collected – Patient-level, Visit-level, and Swab-level Conclusion We conclude that environmental contamination of surfaces in the rooms of COVID-19 patients is nearly universal and persistent. Patients with greater independence are more likely than fully dependent patients to contaminate their immediate environment. Disclosures All Authors: No reported disclosures
ABSTRACT
BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.