Influenza vaccine

What is the flu?

The flu, more scientifically known as influenza, is a highly contagious respiratory infection. The influenza virus usually enters the body through membranes in the mouth, nose, or eyes.

When a person with the flu coughs or sneezes, the virus then becomes airborne and can be inhaled by anyone nearby. You can also get the flu if you’ve touched a contaminated surface and then touch your nose or mouth.

Who's at risk?

  • School-age children
  • Older adults
  • People with specific health conditions
Generic picture of young schoolchildren raising hands in class

Types of Influenza

There are 3 types of flu viruses:

  • Type A: Found in humans and many animals including ducks, chickens, pigs.  Type A is divided into subtypes that can be found worldwide including H1N1, H1N2 and H3N2 viruses.
  • Type B: Found in humans.  Outbreaks can cause epidemics, but the illness it produces is usually milder than Type A.
  • Type C: Found in humans and animals including pigs and dogs.  Type C flu viruses are not thought to cause large epidemics and generally cause only mild respiratory infections.
Symptom onset Abrupt Gradual
Fever Usually; lasts 3–4 days Rare
Aches Usually; often severe Slight
Chills Fairly common Uncommon
Fatigue, weakness Usual Sometimes
Sneezing Sometimes Common
Stuffy nose Sometimes Common
Sore Throat Sometimes Common
Headache Common Rare
Chest discomfort, cough Common; can be severe Mild to moderate; hacking cough

If you think you have the flu, contact your doctor immediately.  There are a number of prescription antivirals that may help make your illness milder or may help you feel better faster.

Did you know?

Taking antivirals within the first 2 days of onset flu symptoms may reduce the duration of the flu?

Relieving flu symptoms

Several over-the-counter medications, such as ibuprofen and acetaminophen, can help you feel better. Common medicines include:

  • Analgesics — Relieve aches and pains, and reduce fever.
  • Antihistamines — Work by helping dry a runny nose and watery eyes by blocking histamines; they often cause drowsiness.
  • Expectorants — Work by thinning mucus so that it can be coughed up more easily.
  • Cough suppressants — Work by quieting a cough. They are usually recommended for dry (non–mucus-producing) coughs.
  • Decongestants — Work by reducing nasal congestion.

Wash your hands

The flu virus can spread by direct contact, such as sharing drinks, or through indirect contact, such as when an infected coworker sneezes on her hands and touches an object like the lunchroom microwave door. The influenza virus can live for 2 to 8 hours on surfaces.

Flu vaccines

The flu vaccine preparation is based on the strains of the flu viruses that are in circulation at the time.  There are 2 types of flu vaccines:

  • Flu Shot - vaccine given with a needle, usually in the arm
  • Nasal Spray - vaccine taken via a spray in the nose.

Information from WebMD and Florida Hospital was used on this page.