The flu, or influenza, is a viral infection that mainly affects the respiratory system. Its symptoms are often similar to those of the common cold and feature a runny or stuffy nose, cough, sore throat, aches and pains, fatigue and sometimes fever. The flu is contagious and can be passed from person to person through droplets that are transmitted when a person talks, sneezes or coughs. This period of contagiousness can last for more than a week.
In most people, the flu usually causes a minor, inconvenient and rarely serious illness. There are exceptions to this rule, however. For one, flu viruses differ, and some are more severe than others. That's why the flu often varies in severity from year to year.
Also, some groups are more susceptible to complications related to the flu. This includes the elderly, children under 5, pregnant women, Native Americans and people with a variety of health conditions, including asthma, lung disease and blood disorders. Flu complications can include pneumonia, sinus infections, ear infections and the worsening of an existing health condition. In some cases, flu can lead to death.
Prevention and Treatment
The best weapon available for fighting the flu is to get vaccinated against it. This is recommended for nearly everyone over the age of 6 months, with just a few exceptions. The vaccine, which is usually administered in the fall as an injection or a nasal spray, allows the body to develop antibodies to protect itself against the flu.
If you get the flu, antiviral drugs can help fight the flu virus and its symptoms. These drugs also can prevent complications, such as pneumonia, and they can often shorten the flu duration by one or two days.
When someone has the flu, it's also important to watch for potential severe complications. These include trouble breathing, severe pain and vomiting, difficulty eating and symptoms that appear to be going away but then return with other complications. Anyone with these symptoms should go to the emergency room right away.
SOURCES: U.S. Centers for Disease Control and Prevention
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