Flu vaccines are your first line of defense to stop the flu (influenza), a contagious respiratory (breathing) illness caused by the influenza virus. Although most cases are mild, the flu can lead to serious complications, hospitalizations and sometimes even death.
Getting your flu shot helps protect you and your loved ones against the flu. By getting vaccinated, you also help protect people in your community who can’t get vaccinated or are at higher risk for complications.
At Banner Health, your health and well-being are our top priority. Here is everything you need to know about flu shots to prepare for flu season.
The flu vaccine triggers your body’s immune system to create antibodies that protect you against influenza viruses. These antibodies develop about two weeks after you get your shot.
Each year, the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) identify the most common flu strains for the upcoming flu season.
Vaccine manufacturers then develop a new vaccine formula based on the identified flu strains. This formulation contains weakened or inactivated versions of these flu viruses.
Flu strains can vary from year to year, so you must get a flu shot every year to stay protected.
The CDC recommends that everyone older than six months of age get a flu vaccine, with only a few exceptions (see below).
Flu vaccinations are even more important for people at high risk of flu complications. These include:
Some individuals should consult their health care provider before being vaccinated. These include:
*In the past, flu vaccines were made using egg-based processes. However, current flu vaccines have very low egg protein content, and studies have shown that most people with egg allergies can safely receive the flu vaccine. If you have an egg allergy, talk to your provider before getting vaccinated to determine what’s right for you.
In the United States, the best time to get a flu vaccine is in September or October. Flu season usually peaks between December and February. Remember that it takes two weeks after your flu shot for your immune system to create the antibodies that will protect you against this season’s flu strains.
Different types of flu vaccines are available to suit various age groups and preferences. The standard methods of receiving flu vaccines include:
1. Standard-dose flu shot. This flu shot is the most common type of flu vaccine and is given as an injection (shot) into the muscle, usually in the arm. It contains inactivated (killed) flu viruses and is approved for everyone age 6 months or older.
Several different brands of flu shot vaccines are available in the United States, including two brands (Flucelvax Quadrivalent and Flublok Quadrivalent) that are entirely egg-free for those with egg allergies.
2. Nasal spray flu vaccine (FluMist). The nasal spray flu vaccine is made with live, weakened flu viruses that do not cause the flu. It is typically recommended for healthy individuals between 5 and 49 years old who are not pregnant.
Unlike the flu shot, the nasal spray vaccine is administered by spraying a small amount into each nostril. This makes it a needle-free option.
3. High-dose flu vaccine. This flu vaccine is for people aged 65 years and older. It contains four times more virus pieces than the regular flu vaccine, providing a stronger immune system response.
4. Intradermal vaccine. This flu vaccine uses a smaller needle that injects the vaccine into the skin instead of the muscle. This option is available for adults aged 18 to 64 years. It is just as effective as the regular vaccine.
Some flu vaccine options may not be available near you, and some versions may not be right for you. Your health care provider can help you choose the right flu vaccine.
The vaccine’s effectiveness varies each year, but generally it will:
Flu vaccines prevent 30% to 70% of all hospitalizations due to flu and pneumonia. In older people living in nursing homes and assisted living facilities, vaccinations are 50% to 60% effective in preventing hospitalization or pneumonia and 80% effective in preventing death due to the flu.
Flu vaccines are the first and best way to reduce your chances of getting and spreading the flu to others. Hundreds of millions of Americans have safely received flu vaccines over the past 50 years, and extensive, ongoing research proves their safety.
The most common side effect of the flu shot is mild soreness and redness where the shot was given. You cannot get the flu from the flu vaccine. However, you may have mild symptoms for one to two days as your body builds the antibodies that will protect you. These include:
Severe allergic reactions are very rare. They include difficulty breathing, hives, a rapid heartbeat, weakness and swelling around the eyes or lips. Call 911 or seek emergency care if you experience these symptoms.
While the flu can cause stomach issues in children, it is not the same thing as stomach flu. The stomach flu (medically known as viral gastroenteritis) is caused by different viruses and causes stomach problems, such as diarrhea and vomiting. It does not cause breathing issues.
The flu vaccine can’t give you the flu. It also doesn’t increase your risk for other viruses like COVID-19. The vaccines contain inactivated or weakened viruses, meaning the viruses can’t replicate and cause illness in your body.
Sometimes side effects from the flu vaccine are mistaken for the flu itself. However, this is just your body’s immune system building the antibodies it needs to protect you. These side effects should go away within a day or two (see above for more about side effects).