Symptoms:

• Fever - may be high
• Headache
• Tiredness
• Dry cough
• Sore throat
• Stuffy, congested nose
• Muscle aches and stiffness

Other symptoms may include:

• Nasal discharge
• Shortness of breath
• Wheezing
• Croupy cough
• Chills
• Fatigue
• Malaise
• Sweating
• Loss of appetite
• Vomiting
• Dizziness
• Worsening of underlying illness, such as asthma or heart failure

Signs and tests:

The evaluation of an individual with flu symptoms should include a thorough physical exam and, in cases where pneumonia is suspected, a chest x-ray.

Additional blood work may be needed. They may include a complete blood count, blood cultures, and sputum cultures.

The most common method for diagnosing the flu is an antigen detection test, which is done by swabbing the nose and throat, then sending a sample to the laboratory for testing.

The results of these tests can be available rapidly, and can help decide if specific treatment is appropriate. However, when flu is widespread in the community the diagnosis can often be made by simply identifying symptoms without further testing.