​​​​​​​​​​​​​​​​Seasonal Flu - Influenza

Information for Flu Care Providers - ILI Surveillance Reports

Influenza (flu) severity varies from year to year, but flu always brings serious consequences


The prevention of influenza is important every year. The flu vaccine lowers the risk of influenza-related illness, hospitalization, and death.

Fight-Flu-Consumer-300x250.pngThe COVID-19 pandemic means preventing influenza during 2020–21 is more important than everInfluenza and COVID-19 share many symptoms. Preventing influenza means fewer people will need to seek medical care and testing for possible COVID-19 or influenza. And increasing flu vaccination uptake saves healthcare resources for COVID-19 and other conditions. Begin recommending flu vaccine now, and vaccinate throughout the flu season, providing extra outreach to those at highest risk of severe COVID-19 or severe influenza.

Flu Vaccine prevents the flu and severe outcomes of the flu


Flu Vaccine is not always a perfect match for the circulating flu virus types. But there are flu outbreaks every year that cause severe illness.  Flu vaccine prevents:

  • Missed work days
  • Missed school days
  • Additional doctor appointments, medicines, and treatments
  • Flu symptoms that can mimic COVID-19, saving healthcare resources needed for COVID-19 care.  ​​

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.

Symptoms of the Flu

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 (very tired)
  • 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 the Flu Spreads

Most experts believe that flu viruses 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. 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, eyes, or nose.

Period of Contagiousness

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. Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5-7 days after becoming sick. Some people, especially children and people with weakened immune systems, might be able to infect others for an even longer time.

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 things, including:

  • what flu viruses are spreading
  • how much flu vaccine is available
  • when vaccine is available
  • how many people get vaccinated
  • how well the flu vaccine is matched to flu viruses that are causing illness

Flu seasons are unpredictable and can be severe. In the United States, thousands of healthy adults and children have to visit the doctor or are hospitalized from flu complications each year and some die. Studies going back to 1976 have found that flu-related deaths ranged from a low of 4,700 to a high of 56,600 (average 25,500).

During a regular flu season, about 90 percent of deaths occur in people 65 years and older. 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 You Need to Know About the Flu Vaccine​​

​A seasonal vaccine is distributed routinely every year. While there are many different flu viruses, this year the majority of flu vaccines protects against the four viruses that research suggests will be most common. The 2021​-22 influenza vaccine are made to protect against the following four viruses:

  • ​​an A/Victoria/2570/2019 (H1N1) pdm09-like virus;
  • an A/Cambodia/e0826360/2020 (H3N2)-like virus;
  • a B/Washington/02/2019- like virus (B/Victoria lineage)
  • a B/Phuket/3073/2013-like virus (B/Yamagata lineage)​

For more information on the 2021-2022 flu vaccine recommendations please go to https://www.cdc.gov/flu/season/faq-flu-season-2021-2022.htm​​​


A Strong Defense Against Flu: Get Vaccinated! 
Una fuerte defensa contra la influenza (gripe): ¡Vacúnese! 

What You Should Know About  Influenza (Flu) Antiviral Drugs
Lo que debe saber sobre los medicamentos antivirales contra la influenza (gripe) 

Pregnant? You Need a Flu Shot! 
¿Está embarazada? ¡Usted necesita la vacuna contra la influenza! 

Influenza Is a Serious Disease... Make sure your child is protected! 
La gripe (influenza) es una enfermedad grave… ¡Proteja a su hijo! 

Keep your kids safe — get them vaccinated every fall or winter! 
Mantenga a salvo a sus hijos: ¡Vacúnelos cada otoño o invierno! 

Adults 65 and Older Need a Flu Shot 

Fight Flu - English
Fight Flu - Spanish

For Children: 
Ready Wrigley Prepares for Flu Season - Activity Book​

Who Should Get the Flu Vaccine?

Everyone 6 months and older should get a flu vaccine every year by the end of October, if possible. However, getting vaccinated later is OK. Vaccination should continue throughout the flu season, even in January or later. Individuals traveling should get vaccinated at least 2 weeks before travel as it takes 2 weeks for vaccine immunity to develop after vaccination. Some children who have received flu vaccine previously and children who have only received one dose in their lifetime, may need two doses of flu vaccine. A health care provider can advise on how many doses a child should get. It is especially important for certain individuals to get vaccinated. These include:
Individuals who are at a high risk of developing serious complications like pneumonia if they get sick with the flu.
This includes: 

  • Individuals who have certain medical conditions including asthma, diabetes, and chronic lung disease
  • Pregnant women
  • Individuals 65 years and older
  • Indviduals who live with or care for others who are high risk of developing serious complications, for example individuals with certain medical conditions including asthma, diabetes, and chronic lung disease.
  • Health care providers
  • Parents or caregivers of children younger than 6 months, who are too young to be vaccinated

​The Vaccine is NOT Recommended for the Following Individuals: 

  • People with COVID-19 infection. Check with your doctor. 
  • Children younger than 6 months
  • Individuals who have had Guillain-Barré syndrome (GBS) within 6 weeks of getting a flu vaccine

The recommendations for people with egg allergies have been updated for this season. Individuals who have experienced only hives after exposure to egg can get any licensed flu vaccine that is otherwise appropriate for their age and health. Individuals who have symptoms other than hives after exposure to eggs, such as angioedema, respiratory distress, lightheadedness, or recurrent emesis; or who have needed epinephrine or another emergency medical intervention, also can get any licensed flu vaccine that is otherwise appropriate for their age and health, but the vaccine should be given in a medical setting and be supervised by a health care provider who is able to recognize and manage severe allergic conditions. (Settings include hospitals, clinics, health departments, and physician offices). Individuals with egg allergies no longer have to wait 30 minutes after receiving their vaccine.​

    Where can I get a flu shot in our community?

    There are many resources in Kane County for residents to receive flu shots:

    • Adult and Pediatric Health Practices at their office locations
    • Community Health Centers at their office locations and at community locations:​

      Check with your insurance plan to see if flu shots are covered.  Check with your own provider or contact these providers for clinic times and vaccine costs.

    Sick with the Flu Know What to Do
    Take 3 Actions to Fight Flu infographic.jpg