Avian influenza

Alternative Names

Bird flu; H5N1

Symptoms

Symptoms of avian flu infection in humans depend on the particular strain of virus. In case of the H5N1 virus, infection in humans causes more classic flu-like symptoms, which might include:

• Cough (dry or productive)
• Sore throat
• Fever greater than 100.4°F (38°C)
• Difficulty breathing
• Diarrhea
• Runny nose
• Headache
• Malaise
• Muscle aches

Exams and Tests

If you think you have been exposed to avian influenza, call your health care provider before your visit. This will give the staff a chance to take proper precautions that will protect them and other patients.

In February 2006, the U.S. Food & Drug Administration approved a new, faster test for diagnosing strains of bird flu in people suspected of having the virus. The test is called the Influenza A/H5 (Asian lineage) Virus Real-time RT-PCR Primer and Probe Set. The test gives preliminary results within 4 hours. Older tests required 2 to 3 days.

Your doctor might also perform the following tests:

• Chest x-ray  
• Nasopharyngeal culture  
• Blood differential
• Auscultation (to detect abnormal breath sounds)

Other tests may be done to look at the functions of your heart, kidneys, and liver.

References

US Food and Drug Administration. FDA Approves First U.S. Vaccine for Humans Against the Avian Influenza Virus H5N1. Rockville, MD: National Press Office; April 17, 2007. Release P07-68

US Centers for Disease Control and Prevention. New Laboratory Assay for Diagnostic Testing of Avian Influenza A/H5 (Asian Lineage). MMWR. February 3, 2006/55(Early Release);1.

World Health Organization. Cumulative number of confirmed human cases of avian influenza A/(H5N1) reported to WHO. Geneva, Switzerland: World Health Organization; 2006.

Beigel JH, Farrar J, Han AM, et al. Avian Influenza A (H5N1) Infection in Humans. N Engl J Med. 2005;353:1374-85.