Also known as the flu, influenza is a highly contagious respiratory infection that spreads easily from person to person, mainly when an infected person coughs or sneezes. Approximately 10 percent to 20 percent of Americans come down with the disease during each flu season, which typically lasts from November to March. Common symptoms include fever, cough, headaches, and extreme fatigue.
Each winter, millions of people suffer from influenza, which is a highly contagious infection. Influenza spreads easily from person to person, mainly when an infected person coughs or sneezes. Viruses that infect the nose, throat, and lungs cause influenza, which is also known as the flu. It is usually a mild disease in healthy children, young adults, and middle-aged people. However, influenza can be life threatening in older adults and in people of any age who have chronic illnesses, such as diabetes or heart, lung, or kidney diseases.
Influenza is a respiratory infection that can be caused by a variety of viruses. It differs in several ways from the common cold, which is a respiratory infection that is also caused by viruses. For example, people with colds rarely get fevers, headaches, or suffer from the extreme exhaustion that influenza viruses can cause.
Influenza outbreaks usually begin suddenly and occur mainly in the late fall and winter. Influenza then spreads through communities, creating an epidemic. During the epidemic, the number of cases peaks in about 3 weeks and subsides after another 3 or 4 weeks. Half the population of a community may be affected. Schools are an excellent place for influenza viruses to attack and spread. Therefore, families with school-age children have more infections than other families, with an average of one-third of the family members becoming infected each year.