Influenza

What is Influenza (also called Flu)?
Symptoms of Flu
Complications of Flu
How Flu Spreads
Preventing the Flu: Get Vaccinated
When to Get Vaccinated
Who Should Get Vaccinated?
Use of the Nasal Spray Flu Vaccine
Who Should Not Be Vaccinated
Podcasts
Current Influenza Trends

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 this illness is by getting a flu vaccination each fall.

Every year in the United States, on average:

  • 5% to 20% of the population gets the flu;
  • more than 200,000 people are hospitalized from flu complications, and;
  • about 36,000 people die from flu.

Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications.

Symptoms of Flu

Symptoms of flu include:

  • fever (usually high)
  • headache
  • extreme tiredness
  • dry cough
  • sore throat
  • runny or stuffy nose
  • muscle aches
  • Stomach symptoms, such as nausea, vomiting, and diarrhea, also can occur but are more common in children than adults.

Complications of Flu

Complications of flu can include bacterial pneumonia, dehydration, and worsening of chronic medical conditions, such as congestive heart failure, asthma, or diabetes. Children may get sinus problems and ear infections.

How Flu Spreads

Flu viruses spread in respiratory droplets caused by coughing and sneezing. They usually spread from person to person, though sometimes people become infected by touching something with flu viruses on it and then touching their mouth or nose. Most healthy adults may be able to infect others beginning 1 day before symptoms develop and up to 5 days after becoming sick. That means that you can pass on the flu to someone else before you know you are sick, as well as while you are sick.

Preventing the Flu: Get Vaccinated

The single best way to prevent the flu is to get a flu vaccination each fall. There are two types of vaccines:

  • The "flu shot" – an inactivated vaccine (containing killed virus) that is given with a needle. The flu shot is approved for use in people older than 6 months, including healthy people and people with chronic medical conditions.
  • The nasal-spray flu vaccine – a vaccine made with live, weakened flu viruses that do not cause the flu (sometimes called LAIV for “Live Attenuated Influenza Vaccine”). LAIV is approved for use in healthy people 5 years to 49 years of age who are not pregnant.

About two weeks after vaccination, antibodies develop that protect against influenza virus infection. Flu vaccines will not protect against influenza-like illnesses caused by other viruses.

When to Get Vaccinated

October or November is the best time to get vaccinated, but getting vaccinated in December or even later can still be beneficial. Flu season can begin as early as October and last as late as May.

Who Should Get Vaccinated?

In general, anyone who wants to reduce their chances of getting the flu can get vaccinated. However, all people six months of age and older should get vaccinated each year.

Use of the Nasal Spray Flu Vaccine

It should be noted that vaccination with the nasal-spray flu vaccine is always an option for healthy persons aged 5-49 years who are not pregnant. This vaccine is not subject to prioritization and can be given to healthy 5-49 year olds at any time.

Who Should Not Be Vaccinated

Some people should not be vaccinated without first consulting a physician. They include:

  • People who have a severe allergy to chicken eggs.
  • People who have had a severe reaction to an influenza vaccination in the past.
  • People who developed Guillain-Barré syndrome (GBS) within 6 weeks of getting an influenza vaccine previously.
  • Children less than 6 months of age (influenza vaccine is not approved for use in this age group).
  • People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen.

If you have questions about whether you should get a flu vaccine, consult your health-care provider.

Our thanks to the Centers for Disease Control and Prevention for the use of this article.

Podcasts

Visit PKIDs' Blog for podcasts and blog entries discussing influenza.

Current Influenza Trends and Statistics

Google.org trends for the United States

CDC Surveillance

 

Important disclaimer: The information on pkids.org is for educational purposes only and should not be considered to be medical advice. It is not meant to replace the advice of the physician who cares for your child. All medical advice and information should be considered to be incomplete without a physical exam, which is not possible without a visit to your doctor.


Information is the power
parents have over disease.