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Last reviewed: 24 Oct 2024
Last updated: 24 Oct 2024

Summary

Definition

History and exam

Key diagnostic factors

  • fever
  • cough
  • dyspnoea
  • altered sense of smell/taste

Other diagnostic factors

  • fatigue
  • myalgia or arthralgia
  • sore throat
  • headache
  • rhinorrhoea or nasal congestion
  • sneezing
  • expectoration
  • chest pain/tightness
  • malaise
  • dizziness
  • confusion or delirium
  • gastrointestinal symptoms
  • cutaneous symptoms
  • ocular symptoms
  • signs of pneumonia or acute respiratory distress
  • haemoptysis
  • audio-vestibular symptoms
  • oral mucosal lesions

Risk factors

  • contact with probable or confirmed case
  • residence/work in location with high risk of transmission
  • older age
  • male sex
  • ethnicity
  • residence in a long-term care facility
  • presence of comorbidities
  • obesity
  • cardiovascular disease
  • diabetes
  • chronic respiratory disease
  • chronic kidney disease
  • chronic liver disease
  • pregnancy
  • smoking
  • malignancy
  • cerebrovascular disease
  • mental health disorders
  • solid organ or blood stem cell transplant
  • disabilities
  • dementia
  • immunosuppression
  • HIV infection
  • physical inactivity
  • haemoglobin disorders
  • hypertension
  • substance use disorders
  • children with certain underlying conditions
  • vitamin D deficiency
  • proton-pump inhibitor use
  • corticosteroid use
  • autoimmune disease
  • thyroid disease
  • Parkinson's disease
  • gout
  • dyslipidaemia
  • surgery
  • blood groups A and B
  • gut dysbiosis
  • environmental factors

Diagnostic investigations

1st investigations to order

  • real-time reverse transcription polymerase chain reaction (RT-PCR)
  • rapid antigen test
  • pulse oximetry
  • ABG
  • FBC
  • comprehensive metabolic panel
  • blood glucose level
  • coagulation screen
  • cardiac biomarkers
  • serum C-reactive protein
  • serum erythrocyte sedimentation rate
  • serum lactate dehydrogenase
  • serum procalcitonin
  • serum ferritin level
  • blood and sputum cultures
  • chest x-ray

Investigations to consider

  • computed tomography (CT) chest
  • lung ultrasound
  • serology

Treatment algorithm

Contributors

Expert advisers

Jennifer M. Hendrick, MD

Assistant Professor of Medicine

University of Virginia Health System

Division of Infectious Diseases and International Health

Charlottesville

VA

Disclosures

JMH declares that she has no competing interests.

Tom E. Fletcher, MBE, PhD, MBChB, MRCP, DTM&H

Senior Clinical Lecturer and Defence Consultant in Infectious Diseases

Royal Liverpool University Hospital and Liverpool School of Tropical Medicine

Liverpool

UK

Disclosures

TEF is a consultant/expert panel member to the World Health Organization, and is funded by the UK Surgeon General, the NHS, and Liverpool School of Tropical Medicine. TEF is partially supported by the National Institute of Health Research Health Protection Unit (NIHR HPRU) in Emerging and Zoonotic Infections at University of Liverpool in partnership with the UK Health Security Agency (UKHSA; formerly Public Health England), in collaboration with Liverpool School of Tropical Medicine. He is affiliated with Liverpool School of Tropical Medicine. He has received research grants from the Wellcome Trust, Medical Research Council, and the UK Public Health Rapid Support Team (UK-PHRST). The views expressed are those of the author and not necessarily those of the NHS, the NIHR, the Department of Health, or UKHSA.

Robert Fowler, MDCM, MS (Epi), FRCP(C)

H. Barrie Fairley Professor of Critical Care

University Health Network and Interdepartmental Division of Critical Care Medicine

Director

Clinical Epidemiology and Health Care Research

Institute of Health Policy, Management and Evaluation

Dalla Lana School of Public Health

University of Toronto

Chief

Tory Trauma Program

Sunnybrook Hospital

Toronto

Canada

Disclosures

RF declares that he has no competing interests.

Acknowledgements

Dr Jennifer M. Hendrick​, Dr Tom E. Fletcher, and Dr Robert Fowler would like to gratefully acknowledge Dr Nicholas J. Beeching, previous contributor to this topic.

Disclosures

NJB is partially supported by the National Institute of Health Research Health Protection Unit (NIHR HPRU) in Emerging and Zoonotic Infections at University of Liverpool in partnership with the UK Health Security Agency (UKHSA; formerly Public Health England), in collaboration with Liverpool School of Tropical Medicine. He is affiliated with Liverpool School of Tropical Medicine. The views expressed are those of the author and not necessarily those of the NHS, the NIHR, the Department of Health, or UKHSA.

Peer reviewers

William A. Petri, Jr., MD, PhD

Professor

Division of Infectious Diseases and International Health

University of Virginia

Charlottesville

VA

Disclosures

WAP declares that he has no competing interests.

Xin Zhang, MD, PhD

Attending Physician

The Fifth Medical Center of PLA General Hospital

Clinical Division and Research Center of Infectious Disease

Beijing

China

Disclosures

XZ declares that he has no competing interests.

Ran Nir-Paz, MD

Associate Professor in Medicine

Department of Clinical Microbiology and Infectious Diseases

Hadassah Hebrew University Medical Center

Jerusalem

Israel

Disclosures

RNP has received research grants from US-Israel Binational Science Foundation, Hebrew University, Rosetrees Trust, and SpeeDx. He is chair of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Mycoplasma and Chlamydia Infections (ESGMAC). RNP is a consultant for and has stocks in eDAS Healthcare. He is also chairperson of the Israeli Society for Infectious Diseases guidelines committee.

Editors

Adam Mitchell

Section Editor (Infectious Diseases)/Drug Editor, BMJ Best Practice

Disclosures

AM declares that he has no competing interests.

Irene Chiwele

Lead Section Editor, BMJ Best Practice

Disclosures

IC declares that she has no competing interests.

Julie Costello

Comorbidities Editor, BMJ Best Practice

Disclosures

JC declares that she has no competing interests.

Expert advisers: comorbidities

Martyn Patel, BMBcH, FRCP, MA

Consultant, Older People's Medicine

Norfolk and Norwich University Hospitals

NHS Foundation Trust

Norwich

UK

Disclosures

MP is a contributor to the Oxford Textbook of Otolaryngology, Oxford University Press, 2021, having written a chapter about mental capacity law, for which he received no fee. MP is the NHS representative on the board for Norwich Institute for Healthy Ageing (unpaid role). MP has spoken at the International Forum on Quality and Safety in Healthcare, virtual conference in November 2020 for which he received no fee.

Paul Cockwell, PhD, FRCP

Consultant Nephrologist

Queen Elizabeth Hospital Birmingham

Professor of Nephrology (honorary)

University of Birmingham

Birmingham

UK

Disclosures

PC is immediate past-president and a trustee of UK Kidney Association (UKKA), which is the UK professional organisation that supports healthcare professionals involved in care for, and research, innovation, and education in, kidney disease. UKKA has a broad remit with relationships with multiple partners and includes responsibility for UK Kidney Week, the major educational meeting for UK kidney professionals. PC is medical director for long-term conditions and prevention for NHS Birmingham and Solihull, with responsibilities that include commissioning and transformation of clinical care including areas relevant to the information on chronic kidney disease in the BMJ Best Practice Comorbidity Manager. PC has a non-remunerated research partnership with Boehringer Ingelheim into the epidemiology of chronic kidney disease. PC is author of the BMJ Learning module on chronic kidney disease.

Rajiv Sankaranarayanan, MBBS, FRCP (Lon), FESC, FHFA, PhD

Consultant Cardiologist and Heart Failure Lead

Liverpool University Hospitals NHS Foundation Trust

Liverpool Centre for Cardiovascular Science and NIHR Research Scholar and Honorary Senior Clinical Lecturer

University of Liverpool

Liverpool

UK

Disclosures

RS has research grants from the British Heart Foundation, the NIHR, NHSX (Transformation Agency), AstraZeneca, Biotronik, and the University of Liverpool. RS has received speaker fees/honoraria and travel reimbursement for conferences from AstraZeneca, Novartis, Vifor, Medtronic, Biotronik, Pfizer, Daaichi Sankyo, Roche, and Boehringer. RS has been appointed to: NHS England GIRFT Clinical Lead; NHS England HF Clinical Lead for Cheshire and Merseyside ICB; NHS England PIFU Pathway Committee for Heart Failure (2021); British Cardiovascular Society Vice President-Elect Digital, Communications and Media Committee; British Society for Heart Failure Board Councillor; Clinical Advisory Board of UK’s patient-led charity Pumping Marvellous (2020); and NHS England HF Expert Group.

Rachael Evans, MBChB, FRCP (UK), PhD

Associate Professor (Clinical)

University of Leicester

Honorary Consultant Respiratory Physician

Glenfield Hospital

Leicester

UK

Disclosures

RAE has given a lecture for a non-promotional industry-led session on long COVID by Moderna and provided consultancy for a long COVID project for AstraZeneca totalling <£3000. RAE is the Chief Investigator for a long COVID study funded by Genentec Roche by a grant awarded to the University of Leicester.

Gerry Rayman, MD, FRCP

Consultant Physician and Head of Service

Diabetes and Endocrine Centre and the Diabetes Research Unit

Ipswich Hospitals NHS Trust

Ipswich

UK

Disclosures

GR received funding from Menarini in 2023 to attend the European Association for the Study of Diabetes conference. GR undertakes several research projects on behalf of East Suffolk and North Essex NHS Foundation Trust for pharmaceutical companies which are on the NIHR portfolio (he does not receive payment himself for these).

Sotiris Posporelis, MD, MRCPsych

Consultant Liaison Neuropsychiatrist

King’s College Hospital

South London and Maudsley NHS Foundation Trust

Honorary Senior Clinical Lecturer

Institute of Psychiatry, Psychology & Neuroscience

King’s College London

London

UK

Disclosures

SP declares that he has no competing interests.

Asangaedem Akpan, MPH, FRCP

Consultant Geriatrician

Bunbury Regional Hospital

Western Australia Country Health Service

Bunbury

Western Australia

Visiting Professor

University of Cumbria

Carlisle

Honorary Clinical Associate Professor

University of Liverpool

Liverpool

UK

Disclosures

AA has a limited company that is seeking consultancy work offering reviews of healthcare services, facilitation of workshops, advice/review of publications.

Sanjay Agrawal, MBChB, FRCP

Consultant in Respiratory and Intensive Care Medicine

University Hospitals of Leicester NHS Trust

Leicester

UK

Disclosures

SA is a board member of Action for Smoking for Health (ASH), a healthcare charity related to tobacco control advocacy. SA is the National Specialty Advisor on Tobacco for NHS England and the Special Advisor for Tobacco for the Royal College of Physicians. SA undertakes research on the field of tobacco control but is not chief investigator for any studies at the time of making this declaration nor has he received any money or grants from pharmaceutical companies.

Acknowledgement: Professor Martin Cowie

BMJ Best Practice would like to gratefully acknowledge Professor Martin Cowie for his work on the cardiovascular comorbidity information in the Comorbidities Manager.

Martin Cowie MD, MSc, FRCP, FRCP (Ed), FESC, FHFA, FACC

Professor of Cardiology

Imperial College London (Royal Brompton Hospital)

London

UK

Disclosures

MC is chair of the European Society of Cardiology Digital Health Committee and a trustee of the Atrial Fibrillation Society. He has previously been a non-executive director of the National Institute for Health and Care Excellence. MC provides consultancy advice to AstraZeneca, Servier, Abbott, Medtronic, Boston Scientific, and Genomics PLC. MC declares that none of these interests is directly related to topics advised on for this project.

Acknowledgement: Andrew Lewington

BMJ Best Practice would like to gratefully acknowledge Dr Andrew Lewington for his work on the chronic kidney disease information in the Comorbidities Manager.

Andrew Lewington, BSc (Hons), MBBS, MEd, MD, FRCP

Consultant Renal Physician

Honorary Associate Professor

Nephrology Department

Leeds Teaching Hospitals NHS Trust

Head of MBChB

School of Medicine

University of Leeds

Leeds

UK

Disclosures

AL has been the principal applicant/co-applicant for several grants including: Engineering and Physical Sciences Research Council Research - multiplexed AKI biomarker detection with a single molecule biosensor; Leeds Cares - a novel, non-invasive diagnostic approach to assess kidney transplant health through the targeted measurement of biomarkers of kidney injury and immune response in kidney transplant recipients at the Leeds Teaching Hospitals NHS Trust; Kidney Research Yorkshire - use of enhanced technology to characterise haemodialysis treatment for acute kidney injury (AKI); Bringing It Home - validation of a micro-sampling technique for measuring tacrolimus and creatinine remotely, and to fund a research nurse; British Renal Society - renal function assessment with point of care creatinine in diverse populations (RAPID), and several NIHR grants including on a) Improving the quality of post-discharge care following AKI b) An investigation into the use of remote blood sample collection to reduce health inequalities in patients with mental health disorders c) A comparison of remote blood collection devices: a human factor use study d) Defining the characteristics for a novel automatic device to monitor urine output in catheterised patients e) Leeds Medtech and In-vitro Diagnostic Cooperative Grant Extension f) Surgical MedTech Co-operative for the 2019/20 proof-of-principle funding stream g) A pilot investigation into the use of beta-trace protein for residual renal function estimation in haemodialysis h) Application of functional MRI to improve assessment of chronic kidney disease (AFiRM study) i) SuperResPath-Renal: Quantitative super-resolution technology for a fast, decentralised clinical diagnosis of renal pathologies. AL is the co-author of several manuscripts including on extracorporeal treatments, AKI, kidney function testing prior to contrast-enhanced CT, plasma exchange and glucocorticoids in severe ANCA-associated vasculitis, COVID-19 rapid diagnostics, multimodal image-guided ablation on management of renal cancer in Von-Hippel-Lindau syndrome, and a summary of NICE guidance on CKD. AL is the author of several book chapters on nephrology and AKI. AL has received expenses for accommodation and travel for conferences at which he has given lectures, other than those delivered virtually. AL was a member of the AKI Scientific Program Committee for the ISN World Congress of Nephrology 2020-2021 and Chair of this same committee in 2021-2022.

Acknowledgement: Dr Matthew Jones

BMJ Best Practice would like to gratefully acknowledge Dr Matthew Jones for his advice on a section of the stroke comorbidity content.

Matthew Jones, MD, FRCP

Consultant Neurologist

Manchester Centre for Clinical Neurosciences

Northern Care Alliance

Honorary Senior Lecturer

University of Manchester

Manchester

UK

Disclosures

MJ is the chair of the Association of British Neurologists Education Committee (unpaid position). MJ is a faculty member of an MRCP revision course. MJ has received honoraria from Eisai for educational talks.

Peer reviewers: comorbidities

Martyn Patel, BMBcH, FRCP, MA

Consultant, Older People's Medicine

Norfolk and Norwich University Hospitals

NHS Foundation Trust

Norwich

UK

Disclosures

MP is a contributor to the Oxford Textbook of Otolaryngology, Oxford University Press, 2021, having written a chapter about mental capacity law, for which he received no fee. MP is the NHS representative on the board for Norwich Institute for Healthy Ageing (unpaid role). MP has spoken at the International Forum on Quality and Safety in Healthcare, virtual conference in November 2020 for which he received no fee.

Asangaedem Akpan, MPH, FRCP

Consultant Geriatrician

Bunbury Regional Hospital

Western Australia Country Health Service

Bunbury

Western Australia

Visiting Professor

University of Cumbria

Carlisle

Honorary Clinical Associate Professor

University of Liverpool

Liverpool

UK

Disclosures

AA has a limited company that is seeking consultancy work offering reviews of healthcare services, facilitation of workshops, advice/review of publications.

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