Notifiable condition. Infection control measures, such as standard, droplet, contact, and airborne precautions, are recommended.
High case-fatality rate of approximately 53% among patients with laboratory-confirmed infection.
Most patients present with fever and features of lower respiratory tract infection on admission. Molecular testing is recommended to confirm diagnosis; however, it is usually not available in most clinical settings.
Antiviral therapy is recommended as soon as possible in unwell patients with suspected or confirmed infection. Supportive care and specialised intensive care management are indicated for respiratory failure and other severe complications.
A contagious disease of animals caused by viruses that infect birds and, less commonly, pigs. Avian influenza A viruses are highly species-specific but have infected other mammals and, on rare occasions, have crossed the species barrier to infect humans. Highly pathogenic avian influenza (HPAI) A H5N1 virus originating in poultry and wild birds can be transmitted to humans, with rare cases of infection transmitted between humans.  
This topic focuses on human infection with Asian lineage HPAI H5N1 virus; avian influenza A (H7N9) infection is covered in a separate topic.
Affiliate Assistant Professor of Medicine & Global Health
University of Washington
JRO declares that he has no competing interests.
Chief Medical Officer
National Center for Immunization and Respiratory Diseases
Centers for Disease Control and Prevention
TMU declares that he has no competing interests.
Medical Director of Infection Control
Department of Medicine
SUNY Upstate Medical University
WJ declares that he has no competing interests.
Department of General Practice and Primary Health Care
ADS declares that she has no competing interests.
Pulmonary & Critical Care Medicine
Center for Health Policy/Center for Primary Care & Outcomes Research
Stanford University School of Medicine
NK declares that she has no competing interests.
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