Summary
Definition
History and exam
Other diagnostic factors
- fatigue
- myalgia or arthralgia
- sore throat
- headache
- rhinorrhea 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
- hemoptysis
- 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
- Parkinson disease
- immunosuppression
- HIV infection
- physical inactivity
- hemoglobin disorders
- hemophilia
- hypertension
- epilepsy
- substance use disorders
- children with certain underlying conditions
- vitamin D deficiency
- proton-pump inhibitor use
- corticosteroid use
- autoimmune disease
- inflammatory arthritis
- inflammatory bowel disease
- connective tissue disease
- vasculitis
- multiple sclerosis
- thyroid disease
- gout
- dyslipidemia
- surgery
- blood groups A and B
- gut dysbiosis
- zinc deficiency
Diagnostic investigations
1st investigations to order
- real-time reverse transcription polymerase chain reaction (RT-PCR)
- rapid antigen test
- pulse oximetry
- ABG
- CBC
- 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
Treatment algorithm
Contributors
Authors
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 she has filed a patent application for dupilumab for treatment of COVID-19. However there is no current commercial activity related to this.
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.
Peer reviewer acknowledgements
BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.
Disclosures
Peer reviewer affiliations and disclosures pertain to the time of the review.
References
Key articles
Bhimraj A, Morgan RL, Hirsch Shumaker A, et al. Infectious Diseases Society of America guidelines on the treatment and management of patients with COVID-19. May 2025 [internet publication].Full text
National Institute for Health and Care Excellence. COVID-19 rapid guideline: managing COVID-19. May 2025 [internet publication].Full text
World Health Organization. Therapeutics and COVID-19: living guideline, August 2025. Sep 2025 [internet publication].Full text
World Health Organization. Clinical management of COVID-19: living guideline, June 2025. Jul 2025 [internet publication].Full text
Reference articles
A full list of sources referenced in this topic is available here.
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