4/15/2020

We, the undersigned, are concerned with regards to the discrepancy between UK and WHO
guidance on the period of self-isolation following symptom onset and/or lab diagnosis with
SARS-CoV-2, as well as the guidance on symptoms requiring self-isolation.   Current UK guidance recommends seven days of self-isolation from symptom onset; the WHO
recommends 14 days of self-isolation after symptom resolution.

NHS England guidelines state: “If you have symptoms of coronavirus infection…. do not leave the
house for 7 days from when your symptoms started.”

The WHO recommendations state: “For mild laboratory-confirmed patients who are cared for at
home, to be released from home isolation, cases must test negative using PCR testing twice from
samples collected at least 24 hours apart. Where testing is not possible, WHO recommends that
confirmed patients remain isolated for an additional two weeks after symptoms resolve.”

The available literature is suggestive of a risk of infection beyond seven days from symptom
onset. This has been reported to range from day 10 of symptoms to up to 24 days after
symptom onset.  A study published in The Lancet found the longest observed duration of viral
shedding to be 37 days after symptoms onset in one participant.

We therefore wish to know the rationale behind the UK’s seven day self-isolation guidance, and whether there are plans for PCR testing to be used to determine when individuals can leave self-isolation. PCR testing is available across numerous public, private and academic institutions in the UK. We appreciate the logistical and administrative hurdles that must be overcome to utilise these facilities, along with the global supply chain issues. However, given the importance of PCR testing as a key element in the strategy to navigate away from the need for further enforced lockdowns, we request more granular detail on your five pillar plan, specifically with regards to PCR testing capacity including how much of the 100k target will be PCR tests (given that we need PCR, rather than serological-based testing for the ‘test and trace’ approach).

We are also concerned about the narrow spectrum of symptoms the UK is using as an indication for self-isolation. Initial data demonstrate that other common symptoms include sore throat, fatigue, shortness of breath, and myalgia and we are aware that other countries are using a broader range of symptoms for self-isolation.

We therefore request that the evidence base informing the UK government strategy on self-isolation (both symptoms requiring self-isolation and length of time for self-isolation) be made publicly available, and that more granular detail be provided on your five pillar plan, specifically with regards to PCR testing.

Signatories
Prof Allyson Pollock, Professor of Public Health, Co-director, Newcastle University Centre of Research Excellence in Regulatory Science
Dr Anya Gopfert, Public Health Registrar, Oxford University Hospitals Trust
Dr Michael Gopfert, retired psychiatrist, Liverpool
Dr Rita Issa, Academic Clinical Fellow in General Practice
Dr Miriam Orcutt, Senior Research Fellow, UCL Institute for Global Health
Dr James Smith, Honorary Research Fellow, London School of Hygiene & Tropical Medicine
Dr Nisreen A Alwan, Associate Professor in Public Health, University of Southampton
Dr Rochelle A. Burgess, Deputy Director, UCL Centre for Global Non-Communicable Diseases and Lecturer in Global Health, UCL Institute for Global Health
Professor Paul Elliott, Chair in Epidemiology and Public Health Medicine, Imperial College London
Professor Mark Gilthorpe, Professor of Statistical Epidemiology in the School of Medicine and theLeeds Institute for Data Analytics (LIDA)
Professor Keith Godfrey, Professor of Epidemiology & Human Development, Honorary Consultant UHS, Director Centre for the Developmental Origins of Health and Disease, MRC Lifecourse Epidemiology Unit University of Southampton
Dr Maria van Hove, Junior Doctor, London School of Hygiene and Tropical Medicine
Professor David Hunter, Richard Doll Professor of Epidemiology and Medicine, Nuffield Department of Population Health, University of Oxford
Professor Guiqing Lily Yao, Professor of Health Economics, University of Leicester
Professor Nuala McGrath, Faculty of Medicine, Southampton General Hospital
Professor Martin McKee, Professor of European Public Health, London School of Hygiene andTropical Medicine
Professor Andrew Phillips, Professor of Epidemiology and Biostatistics, Institute for Global Health, University College London
Professor Maggie Rae, President, Faculty of Public Health
Professor Rosalind Raine, Head of Department of Applied Health Research, University College London and Director, NIHR ARC North Thames
Professor Elio Riboli, Professor in Cancer Epidemiology and Prevention, School of Public Health,Imperial College London
Professor Paul Roderick, Professor of Public Health, University of Southampton
Professor Sonia Saxena, Professor of Primary Care, Faculty of Medicine, School of Public Health,Imperial College London
Professor Nicola Shelton, Professor of Population Health, Epidemiology and Public Health,University College London
Professor Paolo Vineis, Chair in Environmental Epidemiology, MRC Centre for Environment andHealth School of Public Health, Imperial College London
Dr Anne Wilson, Lecturer in Epidemiology, Liverpool School of Tropical Medicine



**If you are a public health specialist, epidemiologist, scientist in a relevant field or healthcare professional and would like to publicly support this letter, please add your name, specialty and affiliation below**

Full list of signatories will be available to view here:  https://docs.google.com/spreadsheets/d/17mHL_-gaen0CyuuHekZUvxD_pUAqwwZ2ICS8CMooHi0/edit?usp=sharing