Frequently asked questions

What is influenza (flu)?
When does flu occur?
Who gets the flu?
What are the symptoms of flu?
How serious is the flu?
How is the flu spread?
How can you prevent the flu?
What are good health habits?
What kinds of flu vaccine are available?
Can either kind of vaccine give you the flu?
How effective are the vaccines?
Once you get sick with the flu, is there any treatment?
Does past infection with influenza make a person immune?
Who should get flu vaccine this year?
Where can I get a flu vaccination?
Where can I get more information about flu?

What is influenza (flu)?
Influenza, commonly called "the flu," is a lung (respiratory) infection caused by the influenza virus. Although someone with a mild case of flu may have symptoms similar to a cold, most cases of flu are more serious than the common cold. The flu virus changes slightly each year, so each year a new batch of vaccine must be made.

When does flu occur?
Flu occurs in the United States most often in the winter. Flu-like symptoms in summer months are usually due to other viruses.

Who gets the flu?
Anyone who has not been vaccinated with the current year's flu vaccine can get influenza. Each year in the United States, about 5-20% of the population gets the flu.

What are the symptoms of flu?
The symptoms include fever, headache, dry cough, muscle aches, tiredness and weakness, with congestion in the nose, throat, and lungs. Children may have nausea, vomiting and diarrhea, but these symptoms are uncommon in adults. The symptoms usually last about three to five days, but in more serious infections, complications can occur and the illness may last longer.

How serious is the flu?
For most healthy children and adults, the flu will be serious enough to require bed rest, but most will recover within a week. Flu is most serious for very young children, the elderly, and people with certain medical conditions such as cancer, chronic lung or kidney disease, insulin-dependent diabetes, or a weakened immune system. Each year in the United States, more than 200,000 people need to be hospitalized because of flu complications, and about 36,000 people die from flu. Most deaths occur in people 65 years of age and older.

How is the flu spread?
Influenza spreads easily from person-to-person when an infected person coughs or sneezes. This releases droplets from the nose and throat that contain the flu virus. The flu virus can also be spread when someone touches something that has virus on it, and then touches their nose, eyes or mouth. The flu can be spread from an infected person from the day before they get sick until about seven days after they first have symptoms, so they are contagious before they even know they are sick.

How can you prevent the flu?
The best way to avoid the flu is to get vaccinated each year during the flu season, if vaccine is available. Vaccine is especially important for people who are most at risk for serious flu infections. Good health habits also go a long way toward preventing the spread of many diseases, including the flu.

For more information, download Preventing the spread of germs, available in seven languages.

What kinds of flu vaccine are available?
There are two kinds of flu vaccine: the flu shot is an inactivated vaccine (contains killed flu virus) that is given in a needle. This vaccine is approved for people 6 months of age and older.

A flu vaccine made with live, weakened virus that is sprayed into the nose is also available for healthy people 5 to 49 years of age. The nasal spray flu vaccine should not be used if you are pregnant, or have close contact with people with weakened immune systems.

Can either kind of vaccine give you the flu?
No. The flu shot is made from killed influenza virus and can't give you flu; the nasal spray vaccine is made from weakened virus which is not strong enough to infect people.

How effective are the vaccines?
In general, flu vaccines are very safe and effective in preventing serious infections with flu. In healthy people, the vaccine very effectively prevents flu infections. Because new influenza viruses appear each year, the effectiveness of the vaccine can vary from year to year. Studies show that in years when new flu strains emerge, people at risk for serious flu who are vaccinated tend to have milder illness and are less likely to be hospitalized with flu.

Once you get sick with flu, is there any treatment?
Bed rest and liquids are usually enough to treat the flu. Acetaminophen (or other products that don’t contain aspirin) can lessen fever and body aches. Aspirin--and other aspirin-containing products--should not be given to children with the flu. There are some prescription drugs that can reduce the severity of influenza in people at risk for serious infection, if these drugs are taken early in the course of illness. However, these drugs are not a substitute for flu vaccines (flu shot), which are available to at-risk people through their health care provider or local health departments.

Does past infection with influenza make a person immune?
No. Because viruses that cause flu change frequently, people who have had the flu or a flu shot in previous years may become infected with a new strain.

Where can I get a flu vaccination?
Call your health care provider or local health department to find out about getting flu vaccine. In addition, the American Lung Association maintains an online Flu Shot Locator http://www.findaflushot.com/lungusa/. Although the locator may show that no vaccine is available near your home, you should check it periodically, because the supply situation may change.

Where can I get more information about flu?
For more information call the:

• Department of Health -

  • Immunization Program: (360) 236-3595

  • Communicable Disease Epidemiology Section: (206) 418-5500 or toll-free 877- 539-4344

• American Lung Association: 1-800-LUNG-USA.

You can also visit these Web sites:

• Department of Health immunization information: http://www.doh.wa.gov/cfh/immunize/
• CDCs flu Web site: http://www.cdc.gov/flu/