Influenza season begins in October and peaks in January, February or March in the United States, but can occur at any time during the year. According to the Centers for Disease Control and Prevention (CDC), 5 to 20 percent of the U.S. population will get the flu each year. The elderly, young children and people with compromised immune systems are considered high risk for contracting the flu. Those with the flu may experience many common symptoms; however, not everyone will experience all the symptoms.
Fever
When the body is attacked by a viral or bacterial infection, a fever is the immune system's response to fight the infection. By raising the body's temperature, a fever helps to stop the spread of infection. In healthy adults a normal temperature is between 98 and 100 degrees F. Adults are considered to have a fever when their temperature is greater than 101 degrees F. According to the Mayo Clinic, an adult fever is considered dangerous when it reaches is above 103 degrees F. Not everyone who has the flu will develop a fever.
Fatigue
When a person is sick, the body uses its energy stores to help fight the infection. With the flu, daily activities will be difficult to accomplish as a result of extreme fatigue. It will be hard to get out of bed or stay awake for long periods of time. By getting plenty of sleep, the body will be able to fight the infection.
Cough
Coughing is the body's response to irritants in the respiratory tract. When a person coughs, the abdomen and diaphragm work together to force out the irritants in the respiratory tract. A dry cough (not coughing up any phlegm) is common in those who have the flu.
Muscle Ache and Headaches
A person with the flu often experiences muscle aches. Muscle aches occur mainly in the back, arms and legs, causing soreness and stiffness. Headaches are also common in those suffering from the flu.
Complications
According to the CDC, the flu can last for a few days to two weeks, but some people will have severe complications from the flu. The flu can lead to illnesses such as bronchitis and pneumonia. A medical provider should be contacted by those who are considered to be in a high risk group, or those who show signs of pneumonia (sharp pain when breathing deeply, severe cough that produces phlegm and a high fever). The CDC reports that 200,000 people are hospitalized and 36,000 people die each year from the flu.
