Screening of healthcare workers for SARS-CoV-2 highlights the role of asymptomatic carriage in COVID-19 transmission

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Sridhar, Sushmita 
Sparkes, Dominic 
Routledge, Matthew 
Jones, Nick K 

Significant differences exist in the availability of healthcare worker (HCW) SARS-CoV-2 testing between countries, and existing programmes focus on screening symptomatic rather than asymptomatic staff. Over a 3 week period (April 2020), 1032 asymptomatic HCWs were screened for SARS-CoV-2 in a large UK teaching hospital. Symptomatic staff and symptomatic household contacts were additionally tested. Real-time RT-PCR was used to detect viral RNA from a throat+nose self-swab. 3% of HCWs in the asymptomatic screening group tested positive for SARS-CoV-2. 17/30 (57%) were truly asymptomatic/pauci-symptomatic. 12/30 (40%) had experienced symptoms compatible with coronavirus disease 2019 (COVID-19)>7 days prior to testing, most self-isolating, returning well. Clusters of HCW infection were discovered on two independent wards. Viral genome sequencing showed that the majority of HCWs had the dominant lineage B∙1. Our data demonstrates the utility of comprehensive screening of HCWs with minimal or no symptoms. This approach will be critical for protecting patients and hospital staff.


Funder: Addenbrooke's Charitable Trust, Cambridge University Hospitals; FundRef:

Research Article, Epidemiology and Global Health, Human Biology and Medicine, COVID-19, SARS-CoV-2, infectious disease, virology, occupational health, emerging pathogens, Human, Virus
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Conference Name
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eLife Sciences Publications, Ltd
Wellcome (108070/Z/15/Z)
Wellcome (215515/Z/19/Z)
Wellcome (207498?Z/17/Z)
Wellcome (206298/B/17/Z)
Wellcome (210688/Z/18/Z)
Wellcome (200871/Z/16/Z)
Medical Research Council (MR/P008801/1)
NHS Blood and Transplant (WPA15-02)
National Institute for Health Research (Cambridge Biomedical Research Centre)
Academy of Medical Sciences (Clinician Scientist Fellowship)
Engineering and Physical Sciences Research Council (EP/P031447/1)
Engineering and Physical Sciences Research Council (EP/N031938/1)
Cancer Research UK (PRECISION Grand Challenge C38317/A24043)