Learn about Who Needs A Flu Vaccine.




The Flu Vaccine: Questions and Answers


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The flu is more than just a bad cold. For several days, people can suffer with fever, cough, sore throat and body aches. Each year, influenza causes thousands of deaths and hospitalizations. The best way to prevent flu is by getting a flu vaccine.

Each flu season, different flu viruses can spread, and they can affect people differently based on the virus and on their body’s ability to fight infection. Some flu seasons are worse than others and there is no way to predict how severe the flu season will be. All of the 2016-2017 influenza vaccine is made to protect against the following three viruses:

•  A/California/7/2009 (H1N1) pdm09-like virus
•  A/Hong Kong/4801/2014 (H3N2)-like virus
•  B/Brisbane/60/2008-like virus (B/Victoria lineage)

Quadrivalent vaccine that protects against four strains of flu is available in larger quantities this year. In the quadrivalent preparation for 2016-2017, there is protection against an additional B virus (B/Phuket/3073/2013-like virus; B/Yamagata lineage). All of the vaccine supplied by the Vaccines for Children Program in Washington is quadrivalent.

Who should get the flu vaccination?

The Centers for Disease Control and Prevention (CDC) is recommending that everyone over age 6 months get a flu vaccine. Babies under age 6 months are too young to get the flu vaccine, and people who have had a serious severe allergic reaction to flu vaccine in the past should not get one. People who have had severe egg allergy or a very rare nervous system condition called Guillian-Barre syndrome should talk to their doctor before they get a flu shot.

If I got a flu vaccination last year, do I need one again this year?

Yes. Each year, a new vaccine is made from flu viruses that are expected to be present during the season.

When should I get vaccinated?

You should get vaccinated as soon as the vaccine is available. There is still a health benefit in getting a flu shot at any time during the flu season. In the Pacific Northwest, flu activity is usually at the highest level in January or February, and can go longer.

Do children need more than one dose of flu vaccine per year?

In general, children under age 9 need two doses of flu vaccine the first year they start getting the vaccinations. If I child age 6 months to 9 years has not had two flu vaccines total in their lifetime, they should receive two doses this season. The two doses should be separated by at least 4 weeks.

Are there side effects to the vaccine?

Most people do not have any side effects. If they do happen, they are usually mild. The most common side effects are soreness, redness, tenderness or swelling where the shot is given. The flu vaccine cannot give you the flu.

How effective is the flu vaccine?

The effectiveness of the flu vaccine depends on the match between the flu vaccine and the types of flu viruses that are circulating. If there is a good match, the flu vaccine is usually over 60% effective in healthy adults. Flu vaccine is generally somewhat less effective in elderly persons and very young children, but vaccination can still prevent serious complications. The flu vaccine is more effective in healthy people, and it is important for healthy people to receive the flu shot to protect people close to them who may not be healthy.


Is the flu vaccination safe?

Yes, the flu vaccination is very safe. CDC and the Food and Drug Administration (FDA) hold vaccines to the highest safety standards. Flu vaccines have been given to hundreds of millions of people and have been made the same way for decades.

  • As with all vaccines, flu vaccine testing and safety monitoring are done in multiple phases.
  • For vaccines to be approved, the manufacturing facilities and processes must meet standards to make sure that the vaccines are pure and effective.
  • After vaccines are approved, each batch is tested before it is released to check purity and strength. Several systems are in place to watch for possible side effects after vaccines are given.

Why isn't the nasal spray vaccine recommended this season?

The nasal spray flu vaccine is not recommended by the CDC's Advisory Committee on Immunization Practices (ACIP) for the 2016-2017 season. Effectiveness of all flu vaccines is studied each flu season, and effectiveness varies from season to season. Over the last 3 influenza seasons, effectiveness studies in the United States have found that the nasal spray vaccine, which is live-attenuated influenza vaccine (LAIVI, Flumist®), has not been effective, or as effective as the flu shot. So this season, all children should get a flu shot instead of nasal spray vaccine.

What about egg allergy?

Most flu vaccines are made using eggs. If you can eat scrambled eggs without a reaction, you can get a flu vaccination; either a shot or nasal spray. If you get hives after eating eggs, or even a more serious reaction like trouble breathing, you can get a flu shot (not the nasal spray) if the vaccine is given in a medical setting where you can get immediate treatment for a severe allergic reaction if you have one. You should be observed for at least 30 minutes to make sure you will not have a serious allergic reaction. Another type of vaccine using recombinant technology instead of eggs is also available  (RIV3, tradename Flublok) and can be used for people age 18-49.

Is there a special type of vaccine available for seniors?

Yes. there are two products approved for people age 65 years or older, Fluzone High-Dose and FLUADTM, which is a new product in the U.S. this season. FLUADTM contains an adjuvant which is an ingredient to a vaccine to create a stronger immune response. This vaccine was initially approved in Italy in 1997 and has been used in 38 countries since, including Canada. Fluzone High-Dose (Sanofi-Pateur) was introduced in 2011 for people age 65 years or older. This vaccine is 4 times the strength of the regular flu vaccine. In a study of more than 30,000 seniors, the high dose vaccine was 24% more effective than the standard flu vaccine in preventing influenza. There is also evidence that the high dose vaccine prevents more deaths and complications (like pneumonia) from flu in seniors. Right now, the Centers for Disease Control does not specifically recommend FLUADTM or Fluzone High-Dose vaccine for seniors. All people over age 65 should get a flu shot with any of the currently licensed flu vaccines for adults.

Are there other products available?

The intradermal flu vaccine is a shot that is injected into the skin instead of the muscle. The intradermal shot uses a much smaller needle than the regular flu shot. It is recommended for adults 18-64 years of age. It usually causes more skin irritation than the regular flu shot, but there is no deep muscle soreness as there sometimes is with the regular flu shot.

Is there mercury in the flu vaccine?

Most flu vaccines contain thimerosal, which is a preservative that protects vaccines against contamination with germs. Thimerosal does contain ethyl mercury in very small amounts. There is no medical evidence of harm caused by the low doses of thimerosal in vaccines, except for minor reactions like redness and swelling at the injection site.
Thimerosal preservative-free flu vaccines are available, but are usually given to children under age 3 and pregnant women. Neither the nasal spray flu vaccine or the intradermal flu vaccine contain thimerosal or other preservatives. Both options are safe for protecting you and your family from flu.

Does the flu vaccine cause Guillain-Barre syndrome?

In 1976, a type of influenza (swine flu) vaccine was associated with Guillain-Barré Syndrome (GBS). Since then, flu vaccines have not been clearly linked to GBS.

GBS is a rare problem in which a person’s own immune system damages the nerves, causing muscle weakness and sometimes paralysis. If there is a risk of GBS from current flu vaccines, it would be no more than one or two cases per million people vaccinated. This is much lower than the risk of severe influenza, which can be prevented by vaccination. Influenza infection can also lead to GBS.

It is not fully known what causes GBS. It is known that about two-thirds of people who get GBS do so several days or weeks after they have been sick with diarrhea or a lung or sinus illness.

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