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 years 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 is very easy to spread 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.
What are good health habits?
- Clean your hands often with soap and water or an alcohol-based hand cleaner.
- Avoid touching your eyes, nose or mouth.
- Avoid close contact with people who are sick, if possible.
- If you are sick, cover your nose and mouth with a tissue every time you cough or sneeze, and throw the used tissue in a waste basket. If you don’t have a tissue, sneeze or cough into your sleeve.
- After coughing or sneezing, always clean your hands with soap & water or an alcohol-based hand cleaner.
- Stay home and don’t share eating utensils, drinking glasses, towels or other personal items.
Once you get sick with flu, is there any treatment?
Bed rest and liquids are usually enough, and 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 healthcare 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.
Visit Washington State Department of Health for more information.