Influenza (also known as "flu") is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness. Every year, millions of people get sick, hundreds of thousands are hospitalized, and thousands to tens of thousands of people die from influenza. Linn County Public Health urges you to take the following actions to protect yourself and others from the flu.

7 Ways to Prevent the Flu 

  1. Get an annual flu shot. Everyone 6 months & older should get a yearly flu vaccine every season with rare exception. Learn more
  2. Prioritize rest & good nutrition. Getting a good amount of sleep and eating well-balanced meals help to support a strong immune system. 
  3. Wash hands often with soap and water. 
  4. Avoid touching your face. Touching your eyes, nose and mouth causes germs to spread. 
  5. Cover coughs & sneezes. Use a tissue, or the inside of your elbow, when you cough or sneeze.
  6. Clean & disinfect surfaces and objects. Clean and disinfect surfaces that are touched often to reduce germs that can spread flu. 
  7. Avoid close contact with people who are sick. If you are ill, stay home. For flu, CDC recommends that people stay home for at least 24 hours after their fever is gone except to get medical care or other necessities. Fever should be gone without the need to use a fever-reducing medicine. The stay-at-home guidance for COVID-19 may be different.

Symptoms & Diagnosis 

The flu can cause mild to severe illness. Most people who get flu will recover in a few days to less than two weeks, but some people will develop complications (such as pneumonia) as a result of flu, some of which can be life threatening and result in death. 

What are common symptoms of the flu? 

Flu is different from a cold. Flu usually comes on suddenly. People who have the flu often feel some or all of these symptoms:

  • fever or feeling feverish/chills
  • cough
  • sore throat
  • runny or stuffy nose
  • muscle or body aches
  • headaches
  • fatigue (tiredness)
  • some people may have vomiting and diarrhea, though this is more common in children than adults.

Who is at high risk of flu complications? 

Anyone can get sick with flu (even healthy people), and serious problems related to flu can happen at any age, but some people are at high 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 children younger than 5 years, but especially those younger than 2 years old. Learn more

How do I know if I have the flu? 

Your respiratory illness might be the flu if you have fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and/or fatigue. Some people may have vomiting and diarrhea, though this is more common in children. People may be sick with flu and have respiratory symptoms without a fever. 

Flu viruses usually cause the most illness during the colder months of the year. However, influenza can also occur outside of the typical flu season. In addition, other viruses can also cause respiratory illness similar to the flu. Some of the symptoms of flu and COVID-19 are similar, making it hard to tell the difference between them based on symptoms alone. So, it is impossible to tell for sure if you have flu without diagnostic testing to confirm. If your doctor needs to know for sure whether you are sick with flu, there are laboratory tests that can be done.


Most people with flu have mild illness and do not need medical care or antiviral drugs. If you get sick with flu symptoms, in most cases, you should stay home and avoid contact with other people except to get medical care.

If, however, you have symptoms of flu and are in a high risk group, are very sick or worried about your illness, contact your health care provider. CDC recommends prompt treatment for people who have flu or suspected flu who are at high risk of serious flu complications, such as people with asthma, diabetes or heart disease. 

What should I do if I have the flu?

  • If you get very sick, are pregnant, or are 65 years or older, or are otherwise at high risk of flu-related complications, call your healthcare provider. You might need antiviral drugs to treat flu.
  • Stay at home and rest.
  • Avoid close contact with well people in your house so you won’t make them sick.
  • Drink plenty of water and other clear liquids to prevent fluid loss (dehydration).