What Is The Seasonal Flu Vaccine?
Influenza is more than a nuisance. It’s a virus
that can prove deadly, especially to young people and the elderly. According to
the World Health Organization (WHO), an estimated 250,000 to 500,000 people die
annually from the flu across the world.
The seasonal flu vaccine is a way for people ages
6 months and older to protect themselves against the flu. According to WHO,
healthcare providers have administered the flu vaccine for more than 60 years. Because
there is no cure for the flu, the flu vaccine can protect you from getting the flu
or make flu symptoms less severe.
A new flu vaccine is manufactured each year when
WHO and other infection-prevention organizations make recommendations regarding
the types of inactivated flu viruses that should be included in the vaccine.
These viruses are traditionally grown in hens’ eggs and harvested to make the
When you get the flu vaccine, your body starts to
build up antibodies or protective immune cells against the virus. If you are
exposed to the flu virus, your body will make the antibodies faster to beat the
What Flu Vaccine Types Are Available?
Two flu vaccine types that exist
are trivalent and quadrivalent. The trivalent vaccine protects against three
flu virus strains. The 2014-2015 vaccine contained inactivated strains of
A/H3N2, A/H1N1 and influenza B. Quadrivalent vaccines protect against the same
strains as the trivalent, plus an additional strain. The 2014-2015 vaccine
included an additional influenza B strain.
In addition to traditional
formats, trivalent vaccines are available as high-dose flu shots for those ages
65 and older. They can stimulate a stronger immune system response, better
protecting seniors against the flu. Recombinant shots or cell-based vaccines are
given to people ages 18 and older allergic to eggs that cannot get the
traditional flu vaccine.
Healthcare providers administer
the flu vaccine in a variety of forms. These include:
(IM) shot: This shot is given into the shoulder muscle and is the
traditional site for flu injections. Anyone 6 months of age and older can
receive this flu shot type.
shot: This shot uses a shorter needle that does not penetrate to the
muscle. Those ages 18 to 64 can receive this short type.
spray: This inhaled form of the vaccine is approved for healthy people ages
2 to 49. Pregnant women cannot get this flu vaccine form, however.
Quadrivalent vaccines are only
available as traditional IM shots and nasal sprays.
According to the Centers for Disease
Control and Prevention (CDC), children between the ages of 2 and 8 should
get the nasal spray, as long as the child is healthy and has no indications why
they shouldn’t get the vaccine. The CDC does not list any other preferences for
Who Should Get the Flu Vaccine?
Advisory Committee on Immunization Practices (AICP) recommends all people
ages 6 months and older should have the flu vaccination unless they have a
contraindication that would keep them from safely getting the vaccine.
According to WHO,
people who should get the flu vaccine due to their increased risk for getting or
spreading the flu include:
- pregnant women
- the elderly
- children ranging from 6 months to age 5
- those with chronic medical conditions
- healthcare workers
Some people shouldn’t get the traditional
flu vaccine. Healthcare providers are required to screen patients for these
exclusions to minimize risk for allergic reactions. People who should not get
the traditional flu vaccine include:
- those who have had a severe or life-threatening
reaction to the flu vaccine in the past
- those who are allergic to any part of the
vaccine, including gelatin, antibiotics, or eggs
- those with a history of Guillain-Barré Syndrome
- those with a mild illness and are not feeling
well or who have a fever
Talk to your healthcare provider
about alternative options for the flu vaccine.
When Should the Vaccine Be Administered?
According to the CDC, flu vaccines
take roughly two weeks to provide immunity. After you get your flu shot, your
body starts developing infection-fighting antibodies that prevent the flu.
Flu.gov, you should get the flu vaccine as soon as it’s available at your
physician’s office, health department, or other healthcare facility. It usually
becomes available in October, and flu season tends to begin in January or
While there may be a better time for flu vaccine
administration, getting the vaccine at any time can offer protection. Because
flu season can last until May, it’s rarely ever too late to have your flu shot.
Note the flu vaccine will only last for one flu season at a
time. You will need to get another flu vaccine when the next flu season comes
What Are the Flu Vaccine’s Side Effects?
The flu vaccine can cause
symptoms that range from mild to moderate. According to the CDC, the risk for
serious injury or death is possible, but very remote for the flu vaccine. The
occurrence of a severe allergic reaction is less than 1 in 1 million. Severe
reactions typically occur within minutes of receiving the vaccine. Severe
allergic reaction symptoms include:
- facial swelling
- rapid heartbeat
Mild flu symptoms include:
- body aches
- redness, swelling, or soreness at the injection
- sore, red, or itchy eyes
Moderate side effects can occur
if young children get the flu vaccine and the pneumococcal vaccine (PCV13) at
the same visit. A fever that triggers seizures can occur.
It’s a myth that you can get the
flu from the flu vaccine. The flu vaccine contains inactivated flu viruses.
Because the viruses are not “live,” they cannot cause the flu.
How Effective Is the Vaccine?
While the flu vaccine does not
protect against all flu types, it does make you less likely to get the flu.
According to Flu.gov,
you are 60 percent less likely to require flu treatment from a healthcare
provider if you get the flu shot.
According to the CDC, getting the flu
- flu-related hospitalizations for adults by 74
- hospitalizations in people with diabetes by 79
percent and chronic lung diseases by 52 percent
- the risk for flu-related hospitalizations in
people ages 50 and older by 61 percent
The flu vaccine is researchers’
best guess at what flu viruses will circulate in a given year. Some years prove
more effective than others in flu prevention.
What Are the Safety Considerations for the
While there is always potential
for an allergic reaction to the flu vaccine, the vaccine is largely considered
safe. According to Flu.gov, the
CDC and the U.S. Food & Drug Administration closely monitor the flu
vaccine’s safety to ensure the vaccine doesn’t have unintended ill effects.