Screening of healthcare workers for SARS-CoV-2 highlights the role of asymptomatic carriage in COVID-19 transmission
Authors: Rivett Lucy , Sridhar Sushmita , Sparkes Dominic , Routledge Matthew , Jones Nick K , Forrest Sally , Young Jamie , Pereira-Dias Joana , Hamilton William L , Ferris Mark , Torok M Estee , Meredith Luke ,   The CITIID-NIHR COVID-19 BioResource Collaboration, Gupta Ravi , Lyons Paul A , Toshner Mark , Warne Ben , Bartholdson Scott Josefin , Cormie Claire , Gill Harmeet , Kean Iain , Maes Mailis , Reynolds Nicola , Wantoch Michelle , Caddy Sarah , Caller Laura , Feltwell Theresa , Hall Grant , Hosmillo Myra , Houldcroft Charlotte , Jahun Aminu , Khokhar Fahad , Yakovleva Anna , Butcher Helen , Caputo Daniela , Clapham-Riley Debra , Dolling Helen , Furlong Anita , Graves Barbara , Gresley Emma Le , Kingston Nathalie , Papadia Sofia , Stark Hannah , Stirrups Kathleen E , Webster Jennifer , Calder Joanna , Harris Julie , Hewitt Sarah , Kennet Jane , Meadows Anne , Rastall Rebecca , Brien Criona O , Price Jo , Publico Cherry , Rowlands Jane , Ruffolo Valentina , Tordesillas Hugo , Brookes Karen , Canna Laura , Cruz Isabel , Dempsey Katie , Elmer Anne , Escoffery Naidine , Jones Heather , Ribeiro Carla , Saunders Caroline , Wright Angela , Nyagumbo Rutendo , Roberts Anne , Bucke Ashlea , Hargreaves Simone , Johnson Danielle , Narcorda Aileen , Read Debbie , Sparke Christian , Warboys Lucy , Lagadu Kirsty , Mactavous Lenette , Gould Tim , Raine Tim , Mather Claire , Ramenatte Nicola , Vallier Anne-Laure , Kasanicki Mary , Eames Penelope-Jane , McNicholas Chris , Thake Lisa , Bartholomew Neil , Brown Nick , Parmar Surendra , Zhang Hongyi , Bowring Ailsa , Martell Geraldine , Quinnell Natalie , Wright Jo , Murphy Helen , Dunmore Benjamin J , Legchenko Ekaterina , Gräf Stefan , Huang Christopher , Hodgson Josh , Hunter Kelvin , Martin Jennifer , Mescia Federica , O'Donnell Ciara , Pointon Linda , Shih Joy , Sutcliffe Rachel , Tilly Tobias , Tong Zhen , Treacy Carmen , Wood Jennifer , Bergamaschi Laura , Betancourt Ariana , Bowyer Georgie , De Sa Aloka , Epping Maddie , Hinch Andrew , Huhn Oisin , Jarvis Isobel , Lewis Daniel , Marsden Joe , McCallum Simon , Nice Francescsa , Curran Martin D , Fuller Stewart , Chaudhry Afzal , Shaw Ashley , Samworth Richard J , Bradley John R , Dougan Gordon , Smith Kenneth GC , Lehner Paul J , Matheson Nicholas J , Wright Giles , Goodfellow Ian G , Baker Stephen , Weekes Michael P 
Published: May 2020

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.