Summary
Definition
History and exam
Key diagnostic factors
- winter season
- current influenza outbreak
- unvaccinated
- fever with cough
Other diagnostic factors
- sore throat
- cervical lymphadenopathy
- dyspnoea
Risk factors
- age ≥65 years
- age 6-59 months
- chronic cardiovascular or respiratory conditions
- diabetes
- haemoglobinopathy
- immunocompromised status
- chronic kidney disease (CKD)
- pregnancy
- carers and household contacts of high-risk groups
- healthcare workers
Diagnostic tests
1st tests to order
- clinical diagnosis
Tests to consider
- molecular assays
- antigen detection tests
- viral culture
- serology
- chest x-ray
Treatment algorithm
exposure to influenza in at-risk populations
adults
children
Contributors
Authors
Kyle Eggleton, MBChB PhD FRNZCGP(Dist)
Associate Dean Rural
Department of General Practice and Primary Health Care
University of Auckland
Auckland
New Zealand
Disclosures
KE declares that he has no competing interests.
Rachel Roskvist, MBChB, FRNZCGP, MHSc
Senior Lecturer
Department of General Practice and Primary Health Care
University of Auckland
Auckland
New Zealand
Disclosures
RR declares that she has no competing interests.
Bruce Arroll, MBChB PhD FRNZCGP
Department of General Practice and Primary Health Care
University of Auckland
Auckland
New Zealand
Disclosures
BA declares that he has no competing interests.
Acknowledgements
Dr Kyle Eggleton, Dr Rachel Roskvist, and Professor Bruce Arroll would like to gratefully acknowledge Dr Cristine Radojicic, a previous contributor to this topic.
Disclosures
CR declares that she is on Advisory boards for CSL Behring and Speakers Bureau Biocryst.
Peer reviewers
Waleed Javaid, MD, FACP, FIDSA
Associate Professor
Medical Director of Infection Control
Infectious Disease
Department of Medicine
SUNY Upstate Medical University
Syracuse
NY
Disclosures
WJ declares that he has no competing interests.
Rachel L. Miller, MD, FAAAAI
Associate Professor of Clinical Medicine and Environmental Health Sciences
Columbia University College of Physicians and Surgeons
New York
NY
Disclosures
RLM declares that she has no competing interests.
Mark Sands, MD, FAAAAI
Chief
SUNY Buffalo School of Medicine
Division Allergy and Immunology
Buffalo
NY
Disclosures
MS declares that he has no competing interests.
An De Sutter, MD, PhD
Associate Professor
Department of General Practice and Primary Health Care
Ghent University
Ghent
Belgium
Disclosures
ADS declares that she has no competing interests.
References
Key articles
Uyeki TM, Bernstein HH, Bradley JS, et al. Clinical practice guidelines by the Infectious Diseases Society of America: 2018 update on diagnosis, treatment, chemoprophylaxis, and institutional outbreak management of seasonal influenza. Clin Infect Dis. 2019 Mar 5;68(6):e1-47.Full text Abstract
Centers for Disease Control and Prevention. Influenza (flu). Feb 2024 [internet publication].Full text
Centers for Disease Control and Prevention. Morbidity and Mortality Weekly Report (MMWR): prevention and control of seasonal influenza with vaccines: recommendations of the advisory committee on immunization practices — United States, 2023–24 Influenza Season. Aug 2023 [internet publication].Full text
UK Health Security Agency. Annual flu programme. Mar 2024 [internet publication].Full text
Centers for Disease Control and Prevention. Child and adolescent immunization schedule: recommendations for ages 18 years or younger, United States, 2024. Nov 2023 [internet publication].Full text
Centers for Disease Control and Prevention. Adult immunization schedule by age: recommendations for ages 19 years or older, United States, 2024. Nov 2023 [internet publication].Full text
Centers for Disease Control and Prevention. Influenza antiviral medications: summary for clinicians. Dec 2023 [internet publication].Full text
Reference articles
A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
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- Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices - United States, 2023-24 influenza season
- Canadian immunization guide chapter on influenza and statement on seasonal influenza vaccine for 2022-2023
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