The flu, or influenza, is a contagious viral infection of the nose, throat and lungs caused by the influenza virus. Every year, between 5 and 20 percent of Americans will suffer with symptoms of the flu. According to the National Institute of Allergy and Infectious Disease, the flu is spread by breathing in respiratory droplets from others' coughs and sneezes or by touching a surface contaminated with influenza virus.
Onset of Symptoms
Symptoms of the flu appear between one and seven days after exposure, most often within two to three days. Symptoms tend to come on suddenly and one of the first symptoms is high fever, according to the World Health Organization. The incubation period for the flu is approximately two days, so it is possible to pass the flu on to someone before you know you are sick.
Fever and Chills
A fever of 100 degrees Fahrenheit or higher is typical. Along with fever, there are generally periods of chills and sweats, as the fever builds and breaks. Fever can be treated with acetaminophen after checking with your doctor. Any fever that persists for more than two days or is higher than 102 degrees Fahrenheit should be evaluated by a physician. While you have a fever you should drink plenty of clear liquids, especially water, to prevent dehydration.
Muscle Aches and Fatigue
During a bout with the flu, the whole body may ache. Flu can bring on muscle aches, especially in the arms, legs and back, according to MayoClinic.com. There can also be overwhelming weakness and fatigue. The muscle aches usually clear up as the disease passes, but the fatigue can last two weeks or more. It is important to get plenty of rest when battling the flu, as this will help alleviate some of the fatigue and weakness.
Headache
The flu is an unpredictable disease and symptoms can vary from person to person. According to the Journal of the American Medical Association, headache is a common symptom of the flu. Headache can be treated with rest and acetaminophen.
Nasal Congestion
According to Centers for Disease Control and Prevention, those with the flu may develop a stuffy or runny nose, along with sneezing. Since respiratory droplets are the most common way the flu spreads, it is important to stay home away from others when suffering any nasal symptoms. Using tissues when needed and taking over-the-counter cold and flu medications can help reduce nasal discharge. Washing your hands often or using hand sanitizer can help reduce the chances of spreading the flu to others. Check with your doctor before taking any flu medication.
Cough and Sore Throat
Flu symptoms also include a sore throat and a dry, hacking cough that irritates the throat even further. Coughs should be covered, as this is another way infected droplets become airborne. Presently, there are influenza-specific vaccinations available and are recommended for those who are at risk, especially the elderly and those with chronic disease.
Complications
Although most people recover from the flu in a week, some are at risk for developing complications. Those with diabetes, asthma, heart disease, women who are pregnant and the elderly should consult their physician immediately if they develop flu symptoms.
