Last reviewed: 26 Feb 2023
Last updated: 08 Dec 2022

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
  • 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
  • thyroid function tests
  • blood glucose level
  • coagulation screen
  • cardiac biomarkers
  • serum C-reactive protein
  • serum erythrocyte sedimentation rate
  • serum lactate dehydrogenase
  • serum interleukin (IL) level
  • serum procalcitonin
  • serum ferritin level
  • serum amyloid A level
  • serum creatine kinase and myoglobin
  • blood and sputum cultures
  • chest x-ray

Investigations to consider

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

Treatment algorithm

Contributors

Expert advisers

Nicholas J. Beeching, MA, BM BCh, FRCP, FRACP, FFTM RCPS (Glasg), FESCMID, DCH, DTM&H

Consultant and Emeritus Professor of Tropical and Infectious Diseases

Royal Liverpool University Hospital and Liverpool School of Tropical Medicine

Liverpool

UK

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.

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.

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.

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 a number of 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 catheterized 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 a number of 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 on 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.

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, & Genomics PLC. MC declares that none of these interests is directly related to topics advised on for this project.

Rachael Evans, MBChB, FRCP (UK), PhD

Associate Professor (Clinical)

University of Leicester

Honorary Consultant Respiratory Physician

Glenfield Hospital

Leicester

UK

Disclosures

RAE has given lectures for non-promotional industry-led sessions on long COVID and provided consultancy for GSK, AstraZenica, Boehringer, and Chiesi, for individual payment and travel expenses totalling <£4000.

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 has been paid for advisory board meetings with the following companies: Safoni Aventis, Abbott Diabetes UK, Lilly Diabetes, Bayer. GR has received lecture fees from Safoni Aventis, Abbott Diabetes UK, Lilly Diabetes, Novonordisk, Napp Pharmaceuticals Ltd.

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.

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

Greater Manchester Neurosciences Centre

Salford Royal Foundation Trust

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.

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

Liverpool University Hospitals NHS Foundation Trust

Visiting Professor

University of Cumbria

Carlisle

Honorary Clinical Associate Professor

University of Liverpool

Liverpool

UK

Disclosures

AA has received honorariums for giving lectures on behalf of Profile Pharma in 2021. AA is an expert committee member of the National Institute for Health and Care Excellence (NICE) quality standards committee on urinary tract infections in adults and Deputy chair of the British Geriatrics Society England Council and Ageing Specialty Research Lead CRN NWC. AA sits on advisory committees for the following research studies: VOICE2 (development and testing of communication skills training for hospital healthcare practitioners caring for people living with dementia), SWOP (social work in older people) and CFIN (cognitive frailty interdisciplinary network). AA has received research funding from the Liverpool CCG and Applied Research Collaborative. He is contributing to developing a heart failure pathway tool for the British Society for Heart Failure and has been invited to contribute to the European Union Geriatric Medicine conference (free conference registration) and British Society for Heart Failure conference (accommodation and travel expenses covered).

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