Universal Admission Screening for SARS-CoV-2 Infections among Hospitalized Patients, Switzerland, 2020

Thomas Scheier,Geri Eich,Urs Karrer,Hugo Sax,Adrian Schmid,Christian Rüegg,Peter W Schreiber,Frank Kube,Adrian Schibli,Aline Wolfensberger

doi:10.3201/eid2702.202318

Abstract

Switzerland began a national lockdown on March 16, 2020, in response to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed the prevalence of SARS-CoV-2 infection among patients admitted to 4 hospitals in the canton of Zurich, Switzerland, in April 2020. These 4 acute care hospitals screened 2,807 patients, including 2,278 (81.2%) who did not have symptoms of coronavirus disease (COVID-19). Overall, 529 (18.8%) persons had >1 symptom of COVID-19, of whom 60 (11.3%) tested positive for SARS-CoV-2. Eight asymptomatic persons (0.4%) also tested positive for SARS-CoV-2. Our findings indicate that screening on the basis of COVID-19 symptoms, regardless of clinical suspicion, can identify most SARS-CoV-2–positive persons in a low-prevalence setting.

Highlights

Switzerland began a national lockdown on March 16, 2020, in response to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
In early 2020, public health officials identified the illness as coronavirus disease (COVID-19) and its causative agent as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
Asymptomatic SARS-CoV-2–positive patients were identified at all 4 hospitals: 1 (12.5%) patient at GZO, 3 (37.5%) patients at KSW, 1 (12.5%) patient at STZ, and 3 (37.5%) patients at University Hospital of Zurich (USZ)

Summary

Introduction

Switzerland began a national lockdown on March 16, 2020, in response to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed the prevalence of SARS-CoV-2 infection among patients admitted to 4 hospitals in the canton of Zurich, Switzerland, in April 2020. These 4 acute care hospitals screened 2,807 patients, including 2,278 (81.2%) who did not have symptoms of coronavirus disease (COVID-19). Asymptomatic persons and healthcare workers can contract and spread the infection among hospitalized patients. Many hospitalized patients, who frequently are >65 years of age, have concurrent conditions, or both, are at risk for severe COVID-19 In consideration of these circumstances, hospitals must take precautions to prevent the spread of SARS-CoV-2. We used the results of this screening to assess SARS-CoV-2 prevalence among hospitalized patients and to evaluate the additional yield of a universal screening strategy compared to a symptomdriven approach

Methods

Results

Conclusion