Summary
Definition
History and exam
Key diagnostic factors
- cough
- typical influenza signs and symptoms
- dyspnea
- fever
- decreased breath sounds
- tachypnea
Other diagnostic factors
- vomiting, diarrhea
- altered mental status
Risk factors
- environmental exposure to Asian lineage A(H7N9) virus
- close contact with infected humans
- laboratory work with A(H7N9) virus
Diagnostic investigations
1st investigations to order
- CBC with differential
- liver function tests (alkaline phosphatase, hepatic aminotransferases, bilirubin)
- CXR
- pulse oximetry
- sputum Gram stain
- sputum and blood bacterial culture
- reverse transcription polymerase chain reaction (RT-PCR) of respiratory specimens for Asian lineage A(H7N9) virus and influenza A and B viruses
Investigations to consider
- viral culture of respiratory specimens
Emerging tests
- serologic testing for A(H7N9)-specific antibody for retrospective diagnosis
Treatment algorithm
unprotected exposed healthcare workers and close contacts of suspected/confirmed case
suspected infection
confirmed illness
Contributors
Authors
Jake Dunning, BSc (Hons), MBBS, MRCP, PhD
Consultant in Infectious Diseases and General (Internal) Medicine
Tuberculosis; Acute Respiratory, Gastrointestinal, Emerging and Zoonotic Infections; and Travel Health (TARGET) Division
National Infection Service
Public Health England
London
UK
Disclosures
JD declares that he has no competing interests.
Justin R. Ortiz, MD, MS
Associate Professor of Medicine
Center for Vaccine Development and Global Health
University of Maryland School of Medicine
Baltimore
MD
Disclosures
JRO is a member of the International Council on Adult Immunization and the scientific community for the Global Influenza Hospitalization Surveillance Network.
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 is a member of the Guideline Development Group for the World Health Organization Standard Guidance for the Clinical Management of Severe Influenza. TMU is 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.
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
- Coronavirus disease 2019 (COVID-19)
- Community-acquired pneumonia
- Atypical pneumonia
More DifferentialsGuidelines
- WHO portal for avian and other zoonotic influenza
- Avian influenza: guidance, data and analysis
More GuidelinesPatient leaflets
Flu
Pneumonia
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