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Influenza infection

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Última revisão: 5 Feb 2026
Última atualização: 19 Aug 2025

Resumo

Definição

História e exame físico

Principais fatores diagnósticos

  • winter season
  • current influenza outbreak
  • unvaccinated
  • fever with cough
Detalhes completos

Outros fatores diagnósticos

  • sore throat
  • cervical lymphadenopathy
  • dyspnea
Detalhes completos

Fatores de risco

  • age ≥65 years
  • age 6-59 months
  • chronic cardiovascular or respiratory conditions
  • diabetes
  • hemoglobinopathy
  • immunocompromised status
  • chronic kidney disease (CKD)
  • pregnancy
  • caregivers and household contacts of high-risk groups
  • healthcare workers
Detalhes completos

Investigações diagnósticas

Primeiras investigações a serem solicitadas

  • clinical diagnosis
Detalhes completos

Tests to avoid

  • broad respiratory pathogen panels
  • serology
Detalhes completos

Investigações a serem consideradas

  • molecular assays
  • antigen detection tests
  • viral culture
  • chest x-ray
Detalhes completos

Algoritmo de tratamento

Inicial

exposure to infected individual(s) in at-risk population

AGUDA

adults

children

Colaboradores

Autores

Kyle Eggleton, MBChB PhD FRNZCGP(Dist)

Associate Dean Rural

Department of General Practice and Primary Health Care

University of Auckland

Auckland

New Zealand

Declarações

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

Declarações

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

Declarações

BA declares that he has no competing interests.

Agradecimentos

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

Michael Ison, MD

Chief

Respiratory Diseases Branch

National Institute of Allergy and Infectious Diseases

Bethesda

MD

Disclosures

MI declares that he has no competing interests.

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.

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

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

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. Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices - United States, 2024-25 Influenza Season. Aug 2024 [internet publication].Full text  Abstract

Centers for Disease Control and Prevention. ​Child and adolescent immunization schedule by age (addendum updated July 2, 2025): recommendations for ages 18 years or younger, United States, 2025. Jul 2025 [internet publication].Full text

Centers for Disease Control and Prevention. Adult immunization schedule by age (addendum updated July 2, 2025): recommendations for ages 19 years or older, United States, 2025. Jul 2025 [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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