Influenza Fact Sheet

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Influenza is a viral infection of the lungs and airways that is also known as “the flu”

Anyone can get influenza. Influenza is spread from person to person by coughing and sneezing. It may also be spread by direct contact with infected people or contaminated objects like door handles or computer keyboards. Influenza can be a serious disease that causes severe complications such as pneumonia. It can also make heart disease or chronic lung disease worse. In the United States, it estimated that 12,000 to 56,000 deaths are caused by influenza each year.

Symptoms of influenza might be confused with the common cold

Influenza and the common cold both have symptoms that affect the throat and nose, but influenza symptoms are usually more severe than cold symptoms. These symptoms include:

  • Fever (100°F or greater)
  • ​Cough
  • ​Sore throat
  • ​Fatigue or tiredness
  • Chills
  • Body aches
  • Stuffy or runny nose
  • Headache

Symptoms usually start 1 to 3 days after being exposed to the influenza virus. Most persons feel better after several days but cough and tiredness may last two weeks or more. 

There are ways to treat influenza

For the quickest recovery from influenza, get plenty of rest; drink fluids like juice, water, or hot tea; and consider a fever-reducing medication, such as acetaminophen (but do not give aspirin or aspirin-containing products to children or teenagers who have flu-like symptoms – including fever). Do not give any medication including over-the-counter remedies to a child without first consulting with your pediatrician. If a fever lasts more than 3 or 4 days, see your healthcare provider. A physician may also prescribe certain antiviral medications. These medications may make symptoms milder if taken within 1 to 2 days of when symptoms begin. However, antiviral medication should be limited to those with severe illness or those at higher risk for complications.

Look out for emergency warning signs that require urgent medical attention.  If you see these warning signs, seek medical care immediately, either by calling your healthcare provider or going to an emergency room. When you arrive, tell the receptionist or nurse about your symptoms. You may be asked to wear a mask and/or sit in a separate area to protect others from getting sick:

In children:

  • ​High or prolonged fever 
  • Fast breathing or trouble breathing 
  • Bluish or gray skin color 
  • Not drinking enough fluids (dehydration)
  • Severe or persistent vomiting
  • Flu-like symptoms improve but then return with fever and worse cough 
  • Worsening of underlying chronic medical conditions
  • Changes in mental status, such as not waking up or not interacting; or seizures
  • Fever with a rash

In adults:
  • High or prolonged fever 
  • Difficulty breathing or shortness of breath 
  • Pain or pressure in the chest or abdomen
  • Sudden dizziness
  • Severe or persistent vomiting
  • Flu-like symptoms improve but then return with fever and worse cough
  • Worsening of underlying chronic medical conditions
  • Confusion

Yearly vaccination is the most important way to prevent influenza

Anyone concerned about getting sick from influenza virus should get a flu vaccine. Getting vaccinated is especially important for people at higher risk of complications from flu. The best time to get the influenza vaccine is as soon as it is available, but any time during the flu season is still a good time to get vaccinated. It takes about 2 weeks after vaccination to develop protection against the influenza virus. Past infection with influenza or immunization with the influenza vaccine does not necessarily protect a person from getting influenza the next year because influenza strains often change from one season to the next.

People who should receive influenza vaccination include:

  • ​Everyone 6 months and older
  • Those at higher risk of complications from influenza, including: 
    • ​Children aged 6 months through 4 years (59 months) 
    • People aged 6 months through 18 years receiving long term aspirin therapy 
    • Pregnant women or women who will be pregnant during the influenza season
    • People 50 years of age and older 
    • People of any age with certain acute or chronic medical conditions, including immunosuppression
    • People who live in nursing homes and other long-term care facilities
  • ​Those who might transmit influenza to the vulnerable people listed above should also receive influenza vaccination, including: 
    • ​Health care personnel (including emergency medical personnel)
    • Household contacts of persons at high risk for complications from the flu
    • Household contacts and out of home caregivers of children less than 6 months of age (because these children are too young to be vaccinated) 
    • Household contacts and out of home caregivers of adults 50 years of age and older

There are some people who should NOT be vaccinated. These include:

  • ​Children less than 6 months of age (influenza vaccine is not approved for this age group) 
  • People who have had a severe, life threatening reaction to an influenza vaccination or any ingredient in the vaccine.

Some people should talk to their doctor before getting the flu shot.  These include:

  • ​People who have an allergy to chicken eggs or any ingredient in the vaccine.
  • People who have ever had Guillain-Barré syndrome (GBS) People who have a moderate-to-severe illness with a fever (they should wait until they are recovered to get vaccinated) 

Influenza vaccine may rarely cause serious side effects in some people 

The viruses in the flu shot are killed (inactivated), so you cannot get the flu from a flu shot. Some minor side effects that could occur are

  • ​Soreness, redness, or swelling where the shot was given
  • Fever
  • Aches
  • Fatigue
  • Cough
  • Headache
  • Hoarseness
  • Sore, red, or itchy eyes
  • Itching

If these problems occur, they begin soon after the shot and usually last 1 to 2 days. People who receive influenza vaccine rarely have any serious problems from it. However, some serious problems can occur, such as severe allergic reactions. 

MORE INFORMATION ON FLU VACCINATION CAN BE FOUND AT http://cdc.gov/flu/protect/vaccine/index.htm

In addition to vaccination, there are everyday steps you can take to protect your health and if you are sick, to prevent spreading influenza to others:

  • ​Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are also effective. 
  • Avoid touching your eyes, nose or mouth. Germs spread this way. 
  • Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it. If tissues are not available, cough or sneeze into your sleeve.
  • Try to avoid close contact with sick people. 
  • If you are sick with flu-like illness, stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.) Keep away from others as much as possible to keep from making others sick.