Influenza (flu) viruses attack the respiratory system. The
usual symptoms include:
The influenza virus is constantly evolving. That means that
the annual flu season is different every year. Some years, most flu cases are
mild. Other years, it can be extremely severe. That’s why it’s important to get
an annual flu vaccination. Doctors target the vaccine to the viruses that are
expected to be most common in the upcoming year.
The flu season can start as early as September and run as
late as May.
Everyone over the age of 6 months should be vaccinated
annually. However, the people most at risk of serious flu complications are:
with compromised immune systems
with chronic illnesses
These people get priority for vaccination if supplies are
low. Serious complications of the flu include pneumonia and dehydration.
There are two types of flu vaccines available in the United
States. The flu shot is an injection of dead (inactivated) virus. It can be
given to most people who are 6 months of age or older. The intranasal spray is
a live, attenuated vaccine. It contains weakened virus. It should not be given
younger than 23 months of age
with a compromised immune system
in close contact with someone who is immunosuppressed
with chronic diseases
or teens on long-term aspirin therapy
Everyone over the age of 6 months should get a flu vaccine
once a year. Most people only need one dose. However, some children under 9 may
need two doses.
You should be vaccinated as early as possible once the
yearly vaccine is made available. It can take several weeks to build immunity.
Who Should Not Get Vaccinated?
Certain people should not get the flu vaccine. This includes
to chicken eggs or other vaccine components
reactions to the flu vaccine
history of Guillain-Barré syndrome (GBS)
While flu vaccination is generally contraindicated in
individuals with a history of GBS, in rare instances, the risk of complications
from the flu might outweigh the risk of the vaccine. Your doctor may also
postpone your flu shot if you’ve had another vaccine within four weeks.
Potential Side Effects
Serious vaccine reactions are extremely rare. However, many
people have mild-to-moderate side effects. These include:
or swelling at the site of the shot
red, or itchy eyes
nose or congestion
Serious allergic reactions are extremely rare.
In 1976 an inactivated swine flu vaccine was linked to GBS.
This is a rare disorder in which the immune system damages the nerves of the
body. Since then, the flu vaccine has not been clearly linked to GBS. If the
flu vaccine can cause GBS, such cases are extremely rare.