Avian influenza A (H5N1) virus infection

Last reviewed: 4 Jun 2022
Last updated: 10 Jun 2022

Summary

Definition

History and exam

Key diagnostic factors

  • cough
  • influenza-like illness
  • dyspnea
  • fever
  • rales, rhonchi
  • wheeze
  • decreased breath sounds
  • tachypnea
More key diagnostic factors

Other diagnostic factors

  • abdominal pain, vomiting, diarrhea
  • altered mental status
  • seizures
Other diagnostic factors

Risk factors

  • close contact with infected birds
  • recent travel to an HPAI-H5N1 virus infected country
  • environmental exposure to H5N1 virus
  • close contact with infected humans
  • laboratory work with H5N1 virus
More risk factors

Diagnostic investigations

1st investigations 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)
More 1st investigations to order

Investigations to consider

  • viral culture
More investigations to consider

Treatment algorithm

INITIAL

close contact of confirmed or probable case

ACUTE

suspected or probable or confirmed infection

Contributors

Authors

Justin R. Ortiz, MD, MS

Affiliate Assistant Professor of Medicine & Global Health

University of Washington

Seattle

WA

Disclosures

JRO 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 declares that he has no competing interests.

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.

An De Sutter, MD, PhD

Associate Professor

Department of General Practice and Primary Health Care

Ghent University

Belgium

Disclosures

ADS declares that she has no competing interests.

Nayer Khazeni, MD, MS

Assistant Professor

Pulmonary & Critical Care Medicine

Associate

Center for Health Policy/Center for Primary Care & Outcomes Research

Stanford University School of Medicine

Stanford

CA

Disclosures

NK declares that she has no competing interests.

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    • Interim guidance on influenza antiviral chemoprophylaxis of persons exposed to birds with avian influenza A viruses associated with severe human disease or with the potential to cause severe human disease
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