What is influenza (also called flu)?
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. The best way to prevent the flu is by getting a flu vaccine each year.
What are the symptoms of flu?
People who have the flu often feel some or all of these symptoms:
*It’s important to note that not everyone with flu will have a fever.
What is the difference between flu and the common cold?
The flu and the common cold are both respiratory illnesses but they are caused by different viruses. Because these two types of illnesses have similar symptoms, it can be difficult to tell the difference between them based on symptoms alone. In general, the flu is worse than the common cold, onset is sudden, and symptoms such as fever, body aches, extreme tiredness, and dry cough are more common and intense. Colds are usually milder than the flu. People with colds are more likely to have a runny or stuffy nose. Colds generally do not result in serious health problems, such as pneumonia, bacterial infections, or hospitalizations.
How does flu spread?
The flu is contagious and spreads from person to person. People with flu can spread it to others up to about 6 feet away. Most experts think that flu viruses are spread mainly by droplets made when people with flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs. Less often, a person might also get flu by touching a surface or object that has flu virus on it and then touching their own mouth or nose.
To avoid this, people should wash their hands often with soap and water. If soap and water are not available, they should use an alcohol-based hand rub to clean their hands. Linens, eating utensils, and dishes belonging to those who are sick should not be shared without washing thoroughly first. Eating utensils can be washed either in a dishwasher or by hand with water and soap and do not need to be cleaned separately.
When is flu contagious?
Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5-7 days after becoming sick. Children may pass the virus for longer than seven days. Symptoms start one to four days after the virus enters the body. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick. Some persons can be infected with the flu virus but have no symptoms. During this time, those persons may still spread the virus to others.
How serious is the flu?
Flu is unpredictable and how severe it is can vary widely from one season to the next depending on many factors, including:
Flu seasons are unpredictable and can be severe. Over a period of 30 years, between 1976 and 2006, estimates of flu-associated deaths range from a low of about 3,000 to a high of about 49,000 people.
During 2009-2010, a new and very different flu virus (called 2009 H1N1) spread worldwide causing the first flu pandemic in more than 40 years. It is estimated that the 2009 H1N1 pandemic resulted in more than 12,000 flu-related deaths in the U.S. In contrast to seasonal flu, nearly 90 percent of the deaths occurred among people younger than 65 years of age.
What are the complications of flu?
Complications of flu can include bacterial pneumonia, ear infections, sinus infections, dehydration, and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes.
Certain people are at greater risk for serious complications if they get the flu. This includes older people, young children, pregnant women and people with certain health conditions (such as asthma, diabetes, or heart disease).
What should I do if I think I have flu?
Stay home and monitor your symptoms. If you have a fever, take antipyretics to keep your fever down, drink plenty of fluids and get plenty of rest. You should not return to work until you have been fever free for 24 hours. If symptoms worsen or persist, consult with your health care provider.