What is fever?

Fever is an increase in your body’s temperature to a range that is above normal (98.6 degrees Fahrenheit). Normal body temperature can change throughout the day by a few degrees. Various factors can increase your body temperature including eating, physical activity, medications, surrounding (room or outdoor) temperature, or a strong emotional response.

Part of your body’s natural defense response to infection is to raise the body temperature. Most pathogens survive best at normal body temperature. Therefore, raising the temperature is your body’s natural way of killing the infectious agent or preventing its spread.

An oral temperature of 99.5 degrees Fahrenheit in a child and over 99 to 99.5 degrees Fahrenheit in adults is considered a fever. Fever can be caused by fairly benign conditions, such as a cold, or by serious conditions, such as influenza and meningitis. Infant teething, recent immunization, autoimmune and inflammatory disorders, and some cancers can cause a fever as well.

Despite their beneficial contribution to fighting infection, an extremely high fever can lead to seizures (called a febrile seizure) in children. These seizures do not usually cause permanent harm, but you should visit your health care professional if your child experiences a seizure. Seek emergency care if a seizure lasts more than a couple of minutes.

If your fever lasts more than 48 hours, is associated with other alarming signs, or causes you concern, seek prompt medical care. Fever in infants and very young children can quickly become serious, so exercise caution if your baby develops a fever. Seek immediate medical care (call 911) if you, or someone you are with, have a fever with excessive crying, difficulty breathing, stiff neck, or confusion. These are signs of a serious or life-threatening illness that should be immediately evaluated in an emergency setting.


What other symptoms might occur with fever?

Fever may be accompanied by other symptoms, depending on the underlying disease, disorder or condition. Fever is usually a sign of infection, which often leads to a variety of symptoms. This section describes relatively common as well as more serious symptoms that may accompany a fever.... Read more about fever informationsymptoms


What causes fever?

Multiple types of infections, inflammatory disorders, and conditions can lead to a fever. More common infections include flu (influenza), pneumonia, appendicitis, and urinary tract infections. Rheumatoid arthritis and other connective tissue inflammatory conditions can also be present with a fever. Your baby may even have a fever when teething. Because there are so many possibilities, it is important to contact your doctor to address your concerns and answer your questions.... Read more about fever informationcauses

Medical Reviewer: McDonough, Brian MD Last Annual Review Date: Jan 8, 2011 Copyright: © Copyright 2011 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.

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