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Diseases » Flu » Symptoms

Symptoms of Flu

Symptoms of Flu: Introduction

Symptoms of the flu can vary greatly in intensity and seriousness among individuals. Symptoms can be mild and "cold-like", including runny nose, sneezing, and nasal congestion. Symptoms can also be more uncomfortable and serious and include fever above 101 degrees F, coughing, body aches, headache, extreme fatigue, and sore throat. Children may experience abdominal pain, vomiting, and seizures.

When the symptoms of the flu break down the body's defences, more serious, even life-threatening infections caused by bacteria can invade the body. These include pneumonia, acute bronchitis, and encephalitis. Certain populations are more at risk for getting the flu and developing its serious complications. They include infants and young children, residents of long-term care facilities, pregnant women, and health care workers. Other people at risk include those who are over the age of 50, are care takers for young children, or who have an immunodeficiency disorder, a suppressed immune system, or a chronic disorder, such as diabetes or cardiovascular disease....more about Flu »

Symptoms of Flu

The list of signs and symptoms mentioned in various sources for Flu includes the 32 symptoms listed below:

Research symptoms & diagnosis of Flu:

Flu: Symptom Checkers

Review the available symptom checkers for these symptoms of Flu:

Flu: Symptom Assessment Questionnaires

Review the available Assessment Questionnaires for the symptoms of Flu:

Flu: Complications

Review medical complications possibly associated with Flu:

  • Pneumonia - This lung infection is one of the most serious possible complications.
  • Bronchitis
  • Secondary bacterial infections
    • Streptococcus aureus bacterial infection
    • Haemophilus influenzae bacterial infection
  • more complications...»

Research More About Flu

Do I have Flu?

Flu: Medical Mistakes

Flu: Undiagnosed Conditions

Diseases that may be commonly undiagnosed in related medical areas:

Home Diagnostic Testing

Home medical tests related to Flu:

Less Common Symptoms of Flu:

Ocassionally other symptoms may also present themselves as symptoms of Flu. 1 of the more common ones are included in the list below:

Wrongly Diagnosed with Flu?

The list of other diseases or medical conditions that may be on the differential diagnosis list of alternative diagnoses for Flu includes:

Flu: Research Doctors & Specialists

Research all specialists including ratings, affiliations, and sanctions.

More about symptoms of Flu:

More information about symptoms of Flu and related conditions:

Other Possible Causes of these Symptoms

Click on any of the symptoms below to see a full list of other causes including diseases, medical conditions, toxins, drug interactions, or drug side effect causes of that symptom.

Article Excerpts About Symptoms of Flu:

The Flu, NIAID Fact Sheet: NIAID (Excerpt)

The symptoms start very quickly and are

  • Headache
  • Chills
  • Dry cough
  • Body aches
  • Fever
  • Stuffy nose
  • Sore throat
Typically, the fever begins to decline on the second or third day of the illness. The flu almost never causes symptoms in the stomach and intestines. The illness that some people often call "stomach flu" is not influenza. (Source: excerpt from The Flu, NIAID Fact Sheet: NIAID)

What to Do About the Flu -- Age Page -- Health Information: NIA (Excerpt)

Flu can cause fever, chills, dry cough, sore throat, runny or stuffy nose, as well as headache, muscle aches, and often extreme fatigue. Although nausea, vomiting, and diarrhea can sometimes accompany the flu, especially in children, gastrointestinal symptoms rarely occur. The illness that people call "stomach flu" is not influenza. (Source: excerpt from What to Do About the Flu -- Age Page -- Health Information: NIA)

What to Do About the Flu -- Age Page -- Health Information: NIA (Excerpt)

Call your doctor if you have any signs of flu and:

  • Your fever lasts; you may have a more serious infection.
  • You have breathing or heart problems or other serious health problems.
  • You are taking drugs to fight cancer or other drugs that weaken your body's natural defenses against illness.
  • You feel sick and don't seem to be getting better.
  • You have a cough that begins to produce phlegm.
  • You are worried about your health. (Source: excerpt from What to Do About the Flu -- Age Page -- Health Information: NIA)

    Flu as a Cause of Symptoms or Medical Conditions

    When considering symptoms of Flu, it is also important to consider Flu as a possible cause of other medical conditions. The Disease Database lists the following medical conditions that Flu may cause:

    - (Source - Diseases Database)

    Flu: Onset and Incubation

    Incubation period for Flu: 1-3 days; perhaps 1-4 days

    Incubation period for Flu: If you get infected by the flu virus, you will usually feel symptoms one to four days later. (Source: excerpt from The Flu, NIAID Fact Sheet: NIAID)

    Medical articles and books on symptoms:

    These general reference articles may be of interest in relation to medical signs and symptoms of disease in general:

    About signs and symptoms of Flu:

    The symptom information on this page attempts to provide a list of some possible signs and symptoms of Flu. This signs and symptoms information for Flu has been gathered from various sources, may not be fully accurate, and may not be the full list of Flu signs or Flu symptoms. Furthermore, signs and symptoms of Flu may vary on an individual basis for each patient. Only your doctor can provide adequate diagnosis of any signs or symptoms and whether they are indeed Flu symptoms.


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