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Avian influenza A(H7N9) virus infection

Last reviewed: 12 Oct 2024
Last updated: 10 Aug 2023

Summary

Definition

History and exam

Key diagnostic factors

  • cough
  • influenza-like illness
  • dyspnea
  • fever
  • decreased breath sounds
  • tachypnea
Full details

Other diagnostic factors

  • vomiting, diarrhea
  • altered mental status
Full details

Risk factors

  • environmental exposure to Asian lineage A(H7N9) virus
  • close contact with infected humans
  • laboratory work with A(H7N9) virus
Full details

Diagnostic tests

1st tests to order

  • CBC with differential
  • LFTs
  • chest x-ray
  • pulse oximetry
  • sputum Gram stain
  • sputum and blood bacterial culture
  • reverse transcription polymerase chain reaction (RT-PCR)
Full details

Tests to consider

  • viral culture
Full details

Treatment algorithm

INITIAL

close contact of confirmed or probable case

ACUTE

suspected or probable or confirmed infection

Contributors

Authors

Jake Dunning, BSc (Hons), MBBS, MRCP, PhD

Consultant and Honorary Clinical Associate Professor in Infectious Diseases and High Consequence Infectious Diseases

Royal Free London NHS Foundation Trust

London

UK

Disclosures

JD declares that he has no competing interests.

Timothy M. Uyeki, MD, MPH, MPP

Chief Medical Officer

Influenza Division

National Center for Immunization and Respiratory Diseases

Centers for Disease Control and Prevention

Atlanta

GA

Disclosures

TMU was a member of the Guideline Development Group for the World Health Organization Standard Guidance for the Clinical Management of Severe Influenza in 2017-2019, with recommendations posted by the World Health Organization in 2022. TMU was a co-chair for the Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 update on diagnosis, treatment, chemoprophylaxis, and institutional outbreak management of seasonal influenza, which published in 2019. He is also the author of several papers cited in this topic.

Acknowledgements

Dr Jake Dunning and Dr Timothy M. Uyeki would like to gratefully acknowledge Dr Justin R. Ortiz, a previous contributor to this topic.

Disclosures

JRO is a member of the International Council on Adult Immunization and the scientific community for the Global Influenza Hospitalization Surveillance Network.

Peer reviewers

Rob Fowler, MDCM, MSc

Senior Scientist

Sunnybrook Health Sciences Centre

Toronto

Ontario

Canada

Disclosures

RF declares that he has no competing interests.

Nelson Lee, MD, FRCP(Lond.), FRCP(Edin.)

Professor

Division of Infectious Diseases

Faculty of Medicine and Dentistry

University of Alberta

Edmonton

Alberta

Canada

Disclosures

NL declares that he has no competing interests.

Michael Ison, MD, MS

Professor

Division of Infectious Diseases

Division of Organ Transplantation

Northwestern University Feinberg School of Medicine

Chicago

IL

Disclosures

MI declares that he received research support, paid to Northwestern University, from Beckman Coulter, Chimerix, and Gilead; is a paid consultant for Celltrion, Chimerix, Farmark, Genentech/Roche, Toyama/MediVector, Seqirus, and Shionogi; and is a member of the DSMB for GlaxoSmithKline and Shionogi.

  • Differentials

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