Influenza (Flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and at times the lungs. Flu is a serious disease that can lead to hospitalization and sometimes even death.

Flu Facts:

The flu can affect people differently, but millions of people get flu every year

Flu can cause fever, cough, sore throat, head and body aches, and fatigue

Flu spreads through droplets that land in the mouths or noses of those nearby. A person is less likely to contract the flu from touching everyday surfaces and objects

Hundreds of thousands of people are hospitalized 

Thousands to tens of thousands of people die from flu-related causes every year

Children younger than 18 are more than twice as likely to develop asymptomatic flu infection than adults 65 and older

3% to 11% of the U.S. population gets infected and develops flu symptoms each year

Peak contagion happens in the first 3-4 days of sickness

In some cases, healthy adults can infect others the day before symptoms begin, and up to a week after becoming sick.

Complications of flu can include bacterial pneumonia, ear infections, sinus infections and worsening of medical conditions, such as congestive heart failure, asthma, or diabetes

Flu vaccination prevents millions of illnesses and flu-related doctor’s visits each year


In 2019-2020 The flu vaccinations prevented:

7.5 million influenza illnesses (flu)

3.7 million influenza-associated medical visits

105,000 influenza-associated hospitalizations

6,300 influenza-associated deaths



What is the Flu? - CDC

Key Facts About the Flu - CDC

How does the Flu Spread? - CDC

Flu Symptoms and Diagnosis - CDC

Treatment for the Flu - CDC


For more information and assistance, the Delaware County Health Department Wellness Line is available 24 hours a day, 7 days a week. In addition to responding to phone calls, the Wellness Line also responds to email inquiries.

Phone: (484) 276-2100 (Available 24/7)


Contact Us

  •   201 West Front Street,
         Media, PA 19063
  •   8:30AM - 4:30PM
           Monday - Friday
  •   610-891-4000

About Delaware County

Delaware County, presently consisting of over 184 square miles divided into forty-nine municipalities is the oldest settled section of Pennsylvania.

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