What causes flu-like symptoms?

Many types of infections, inflammatory disorders, and other conditions can cause flu-like symptoms. Common infections include flu (influenza), pneumonia, appendicitis, and urinary tract infections. Symptoms of rheumatoid arthritis and other connective tissue conditions can include flu-like symptoms. There are many possible causes of flu-like symptoms, so talk with your medical professional about your symptoms.

Infectious causes of flu-like symptoms

Flu-like symptoms are associated with many different types of infections:

  • Appendicitis
  • Bronchitis
  • Common cold (viral respiratory infection)
  • Dengue
  • Influenza
  • Lyme disease
  • Malaria (international travel)
  • Meningitis (infection or inflammation of the sac around the brain and spinal cord)
  • Pneumonia
  • Rocky Mounted Spotted Fever
  • Septic arthritis (infectious arthritis)
  • Tuberculosis (serious infection affecting the lungs and other organs)
  • Urinary tract infection
  • West Nile virus

Other causes of flu-like symptoms

Flu-like symptoms can also be caused by inflammatory conditions and other abnormal processes including:

  • Blood transfusion
  • Dermatomyositis
  • Electrolyte disturbances (potassium, calcium, magnesium)
  • Polymyalgia rheumatica
  • Rheumatoid arthritis (chronic autoimmune disease characterized by joint inflammation)
  • Systemic lupus erythematosus (disorder in which the body attacks its own healthy cells and tissues)

Questions for diagnosing the cause of flu-like symptoms

To diagnose the underlying cause of flu-like symptoms, your doctor or licensed health care practitioner will ask you several questions related to your symptoms. You can best help your health care practitioner in diagnosing the underlying cause of flu-like symptoms by providing complete answers to these questions:

  • What symptoms are you experiencing?
  • When did your symptoms start?
  • Where have you traveled recently?
  • Have you had a fever? If so, how high was the fever?
  • Have you had any trouble breathing, neck pain or stiffness, or bleeding?

What are the potential complications of flu-like symptoms?

Complications associated with flu-like symptoms can be progressive and vary depending on the underlying cause. In some cases, flu-like symptoms can be caused by serious diseases, such as meningitis, that can rapidly result in life-threatening complications.

It is important to contact your health care provider promptly when you experience flu-like symptoms. Once the underlying cause is diagnosed, following the treatment plan that you and your health care provider design specifically for you can help reduce any potential complications including:

  • Absenteeism from work or school

  • Dehydration due to accompanying diarrhea or vomiting, reduced fluid intake, fever, or increased sweating

  • Disability

  • Inability to perform daily tasks

  • Poor quality of life

  • Pregnancy complications, such as miscarriage, birth defects, and serious newborn infections

  • Seizures

  • Shock, coma, and organ failure

  • Sleep disturbance


  1. General symptoms of lymphoma. Lymphomation.org. http://www.lymphomation.org/symptoms.htm.
  2. What to Do If You Get Sick: 2009 H1N1 and Seasonal Flu. Centers for Disease Control and Prevention. http://www.cdc.gov/h1n1flu/sick.htm.
  3. Cold and Flu. FamilyDoctor.org. http://familydoctor.org/online/famdocen/home/tools/symptom/517.html.
  4. Kahan S, Miller R, Smith EG (Eds.). In A Page Signs & Symptoms, 2d ed. Philadelphia: Lippincott, Williams & Williams, 2009.

What are flu-like characteristics?

Flu-like symptoms are a group of symptoms that are generally due to infection or inflammation in the body. There are a variety of flu-like symptoms that include:

  • Body aches and pains
  • Chills
  • Cough
  • Fever

What other symptoms might occur with flu-like symptoms?

Flu-like symptoms may occur with other symptoms depending on the underlying disease, disorder or condition. Flu-like symptoms usually indicate an infection or inflammation in the body, which can cause additional symptoms, such as:

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Aug 9, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Infections and Contagious Diseases

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