Influenza (the flu) is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death.
Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications. The best way to prevent the flu is by getting vaccinated each year.
The upcoming season’s flu vaccine will protect against the three influenza viruses that research indicates will be most common during the season. This includes an influenza A (H1N1) virus, an influenza A (H3N2) virus, and an influenza B virus.
Influenza (also known as the flu) is a contagious respiratory illness caused by flu viruses. It can cause mild to severe illness, and at times can lead to death. The flu is different from a cold. The flu usually comes on suddenly. People who have the flu often feel some or all of these symptoms:
- Fever* or feeling feverish/chills
- Sore throat
- Runny or stuffy nose
- Muscle or body aches
- Fatigue (tiredness)
- Some people may have vomiting and diarrhea, though this is more common in children than adults
* It’s important to note that not everyone with flu will have a fever.
Most people who get influenza will recover in a few days to less than two weeks, but some people will develop complications (such as pneumonia) as a result of the flu, some of which can be life-threatening and result in death.
Pneumonia, bronchitis, and sinus and ear infections are three examples of complications from flu. The flu can make chronic health problems worse. For example, people with asthma may experience asthma attacks while they have the flu, and people with chronic congestive heart failure may have worsening of this condition that is triggered by the flu.
People at Higher Risk from Flu
Anyone can get the flu (even healthy people), and serious problems from influenza can happen at any age, but some people are at higher risk of developing serious flu-related complications if they get sick. This includes people 65 years and older, people of any age with certain chronic medical conditions (such as asthma, diabetes, or heart disease), pregnant women, and young children.
Flu is unpredictable and how severe it is can vary widely from one season to the next depending on many things, including:
- what flu viruses are spreading
- how much flu vaccine is available
- when vaccine is available
- how many people get vaccinated
- how well the flu vaccine is matched to flu viruses that are causing illness
One study found that during the 1990s, flu-related deaths in the United States ranged from an estimated 17,000 during the mildest season to 52,000 during the most severe season (36,000 average). Over a period of 31 seasons between 1976 and 2007, estimates of flu-associated deaths in the United States range from a low of about 3,000 to a high of about 49,000 people. During a regular flu season, about 90 percent of deaths occur in people 65 years and older.
The CDC Influenza application for clinicians and other health care professionals makes it easier than ever to find CDC’s latest recommendations and influenza activity updates on your iPad, iPhone or iPod Touch. (Android support will be added in a future update).
When your mobile device is connected to the internet, new information and content will update automatically. This is an official application of the Centers for Disease Control and Prevention.
With this application, you can:
- View updated information on national flu activity
- Find influenza vaccination recommendations endorsed by CDC and the Advisory Committee on Immunization Practices (ACIP)
- Obtain information on diagnosis and treatment of influenza, including antiviral treatment recommendations by CDC and the ACIP
- Obtain information on laboratory testing for influenza
- Find CDC recommendations on influenza infection control
- View videos of CDC subject matter experts discussing influenza topics
- Order official CDC designed print products for posting in the workplace or distributing to patients.
For more information please visit Information For Health Professionals.
For questions and comments, contact CDC-INFO.
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Information for this story, along with links and pictures, provided by the CDC
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Also take a look at their tips on how to take care of people who have the flu
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