Women's Health

Influenza Vaccine, Inactivated or Recombinant

Why get vaccinated?

Influenza vaccine, inactivated or recombinant may prevent influenza illness (flu) that may occur with infection due to the influenza virus.

Flu is a contagious disease that spreads around the United States every year, usually between October and May. Anyone can get the flu, but it is more dangerous for some people. Flu can cause fever and chills, sore throat, muscle aches, fatigue, cough, headache, and runny or stuffy nose. Flu can cause other complications such as sinus infections and pneumonia and can lead to hospitalization and death.

Influenza vaccine, inactivated or recombinant does not contain the influenza virus. It works by triggering your immune system to build a defense to the influenza virus when it comes in contact with it.

There are many variants of the influenza virus and the vaccine will need to be reformulated periodically to cover the current circulating variants.

How is the vaccine given?

Influenza Vaccine, Inactivated or Recombinant comes as a suspension (liquid) to be given intramuscularly (into the muscle) by a healthcare provider.

Influenza Vaccine, Inactivated or Recombinant is given as a single dose each season. Some individuals may have a second dose recommended based on age and prior history of vaccine. If it is recommended that you receive 2 doses, they should be given at least 4 weeks apart.

What should you tell the person who is giving the vaccine?

Tell your vaccine provider if you:

  • have had an allergic reaction to this vaccine, any part of this vaccine, any other vaccine or any drug, food or substance. Tell your vaccine provider about the allergy and what symptoms you had.
  • have had a history of Guillain-Barre syndrome (an autoimmune disorder that causes numbness in the extremities, muscle pain, difficulty walking or standing, and paralysis often triggered by an infection) or have a weakened immune system due to a condition or medication you are receiving.
  • have a fever or are feeling unwell.
  • have ever fainted in association with an injection.
  • are pregnant or are breast-feeding. Influenza Vaccine, Inactivated or Recombinant has not been shown to pose a risk to pregnant women or the fetus. However, flu has been associated with adverse outcomes during pregnancy including early labor and delivery. Talk to your doctor about the right time to receive influenza vaccine during pregnancy.

In some cases, your health care provider may decide to postpone vaccination to a future visit.

What are the risks from vaccination?

Side effects that have been reported with the Influenza Vaccine, Inactivated or Recombinant include:

  • pain, bruising, swelling or redness at the injection site
  • muscle aches, chills or general ill-feeling
  • headache
  • nausea

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • numbness in the extremities, muscle pain, difficulty walking or standing, paralysis
  • rash, shortness of breath or difficulty breathing, swelling of face or throat

People sometimes faint after medical procedures, including vaccination. Tell your provider if you feel dizzy or have vision changes or ringing in the ears.

Adverse reactions should be reported to the Vaccine Adverse Event Reporting System (VAERS). Your health care provider will usually file this report, or you can do it yourself. Visit https://vaers.hhs.gov or call 1-800-822-7967. VAERS is only for reporting reactions, and VAERS staff members do not give medical advice.

How can I learn more?

Brand name(s)

  • Afluria®
  • Fluad®
  • Fluarix®
  • Flublok®
  • Flucelvax®
  • FluLaval®
  • Fluzone®

Other name(s)

  • Flu vaccine
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