Fever and Chills During a Bout of the Flu
Eighty percent of flu cases include a fever. People with the flu typically have fevers greater than 100 degrees Fahrenheit that last for three to four days according to the Utah Department of Health. The fever is your body’s way of fighting the infection.
Viruses like influenza multiply best at 98.6 degrees Fahrenheit, which is your body’s normal temperature. So when the virus infects your body, it sends signals to the hypothalamus, which is the part of your brain that works as the body’s thermostat. The hypothalamus raises your body’s temperature a few degrees (giving you a fever) in order to kill off the viruses.
When you have a fever, you will also get the chills. The reason you develop chills is because your body is confused by this new temperature setting and thinks it’s now too cold – so you begin to shiver. You feel the coldest as your body temperature begins to rise and you feel the hottest when your body temperature begins to drop back down to normal. It may be a little confusing, but it’s how our body fights infections.
Getting Over the Flu
You will start to feel better within two to five days of becoming ill with influenza. However, you may still feel tired and run down for a week or more after you are better. There are treatment options for the flu, such as prescription Tamiflu, but most people recover at home without a prescription. Pregnant women, the elderly, the very young, and those with compromised immune systems are more at risk for developing complications such as pneumonia. These people should seek medical attention if they think they have the flu.
Centers for Disease Control and Prevention. Seasonal Influenza Situation Update: Summary of Weekly FluView. (2013). Accessed February 7, 2013.
Centers for Disease Control and Prevention. Clinical Signs and Symptoms of Influenza. (2009). Accessed February 7, 2013.
US Department of Health and Human Services. Symptoms f the Flu. Flu.gov. Accessed February 8, 2013.
Blum, J. Why do we feel cold when we have a fever? (2002). Howard Hughes Medical Institute. Accessed February 8, 2013.
University of Maryland Medical Center. Sinus Headache. (2011). Accessed February 8, 2013.
Utah Department of Health. Difference between cold and flu symptoms. (2010). Accessed February 8, 2013.
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