Symptoms of bird flu usually start within 1 week of exposure to the virus.

Common symptoms of bird flu include:

• Cough
• Chest congestion
• Chest pain
• Pain worsens during a deep breath
• Difficulty breathing
• Fever
• Headache
• Muscle aches
• Fatigue

Less common symptoms of bird flu include:

• Runny nose
• Sore throat
• Diarrhea
• Nausea
• Abdominal pain

Symptoms of worsening bird flu include:

• Worsening difficulty breathing
• Confusion
• Severe weakness