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Flu Shot Information You Should Know

Flu Shot – Frequently Asked Questions

Flu Shot – Frequently Asked Questions

What kind of flu vaccines are there?

There are two types of vaccines that protect against the flu. The "flu shot" is an inactivated vaccine (containing killed virus) that is given with a needle, usually in the arm. A different kind of vaccine, called the nasal-spray flu vaccine (sometimes referred to as LAIV for Live Attenuated Influenza Vaccine), was approved in 2003. The nasal-spray flu vaccine contains attenuated (weakened) live viruses, and is administered by nasal sprayer. It is approved for use only among healthy people between the ages of 5 and 49 years. The flu shot is approved for use among people over 6 months of age, including healthy people and those with chronic medical conditions.

How do flu vaccines work?
Both flu vaccines (the flu shot and the nasal-spray flu vaccine (LAIV)) work in the same way; they cause antibodies to develop in the body, and these antibodies provide protection against influenza virus infection.

Why should people get vaccinated against the flu?
Influenza is a serious disease, and people of any age can get it. In an average year, the flu causes 36,000 deaths (mostly among those aged 65 years or older) and more than 200,000 hospitalizations in the United States. The "flu season" in the United States is usually from November through April each year. During this time, flu viruses are circulating in the population. An annual flu vaccine (either the flu shot or the nasal-spray flu vaccine) is the best way to reduce the chances that you will get the flu.

When should I get a flu vaccination?
Beginning each September, the flu shot should be offered to people when they are seen by health-care providers for routine care or as a result of hospitalization. Try to get vaccinated in October or November because flu activity in the United States generally peaks between late December and early March.

You can still benefit from getting vaccinated after November, even if flu is present in your community. Vaccine should continue to be offered to unvaccinated people throughout the flu season as long as vaccine is still available. Once you get vaccinated, your body makes protective antibodies in about two weeks.

Does flu vaccine work right away?
No. It takes about two weeks after vaccination for antibodies to develop in the body and provide protection against influenza virus infection. In the meantime, you are still at risk for getting the flu. That's why it's better to get vaccinated early in the fall, before the flu season really gets under way.

Can I get the flu even though I got a flu vaccine this year?
Yes. The ability of flu vaccine to protect a person depends on two things: 1) the age and health status of the person getting the vaccine, and 2) the similarity or "match" between the virus strains in the vaccine and those in circulation.

What is the nasal-spray flu vaccine (or LAIV)?
The nasal-spray flu vaccine (sometimes called LAIV for Live Attenuated Influenza Vaccine) is a new flu vaccine that was licensed in 2003. It is different from the other licensed influenza vaccine (also called the "flu shot") because it contains weakened live influenza viruses instead of killed viruses and is administered by nasal spray instead of injection.

How does the nasal-spray flu vaccine (LAIV) work?
The nasal-spray flu vaccine contains three different live (but weakened) influenza viruses. When the viruses are sprayed into the nose, they stimulate the body's immune system to develop protective antibodies that will prevent infection by naturally occurring influenza viruses.

If you don’t have a family physician, visit the Sioux Valley Physician Finder to locate a provider convenient to you.