Key Facts About Influenza (Flu)
What is Influenza (Flu)?
Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness, and at times can lead to death. The best way to prevent flu is by getting a flu vaccine each year.
Flu is different from a cold. As it usually comes on suddenly. People who are sick with 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.
How Flu Spreads
Most experts believe that flu viruses spread mainly by tiny droplets made when people with flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are nearby. Less often, a person might get flu by touching a surface or object that has flu virus on it and then touching their own mouth, nose or possibly their eyes.
What is Community Immunity?
Community (or herd) immunity helps slow down and stop the spread of disease among people. Community immunity only works when most people in the community have immunity to the disease. People become immune by getting vaccinated or by having had the disease. For some diseases, like pertussis (whooping cough) and measles, at least 9 out of 10 of us must have immunity to keep the diseases from spreading. Community immunity protects us all. Learn more about how community immunity works.
Who Depends on Community Immunity?
We all do, but especially those who can’t fight diseases or are not immune. When you choose to immunize yourself and your family, you also help protect others at risk, like:
- Infants and the elderly who cannot get vaccines because they are too young or too old.
- People with weak immune systems, like those with heart disease or cancer.
- People who are not fully immunized.
Does My Community Have Immunity?
Ask your child care, preschool, or school about their immunization rates. You can find kindergarten immunization rates for Washington State elementary schools here.
Immunize your child on time. Make sure you and your child’s caregivers get immunized too.
Speak up by telling others that your child is fully immunized. Make sure your friends and neighbors know about the risks of not immunizing and the benefits of community immunity.