Influenza prevention is key.
It's much harder to treat influenza
than it is to prevent it.
How do we prevent influenza?
Well, first is get vaccinated.
Stay home if you have influenza.
Patients should not be going to school.
They should not be going to
work when they have influenza.
They can exercise.
Studies have shown that mild to moderate
exercise can boost your immune system.
Patient should eat healthy for the same
reasons, and should keep their hands clean
because this is how they're going
to transmit the influenza virus
to other people and to themselves.
Cover your mouth and nose
when coughing and sneezing.
Don't touch your face because this is
how the virus will get into your body.
Studies have shown that
smiling can actually
increase your immune system function.
And maybe starting
antivirals as prophylaxis
in high-risk group populations.
Now, this means if you have a patient
with influenza sitting in front of you
who might not be a candidate
for antiviral treatment,
they may have an immunocompromised
who is at a really high risk
for influenza complications.
There is a prophylactic dose of antivirals
that can be started in this population to
prevent them from getting the flu virus.
And these antivirals,
while they're not that good
at helping the influenza virus
when you are already sick,
they are pretty good at preventing it
in other members of the community.
Get the vaccine.
You are at least 60% less likely to
become infected with the influenza virus.
Flu viruses used in flu shots are
inactivated, so they cannot cause infection.
And this is a common conversation
I have with my patients.
They will say, "I don't
want to get the flu shot
because the last time I got
the flu shot, I got the flu."
And then I have a conversation
with them that
that is impossible to
happen from the flu shot.
It turns out they got the flu
because it was flu season,
and they could have gotten
their flu shot 2 weeks sooner
to actually give them some
antibodies that might be protective.
But the flu shot cannot cause influenza.
Get the flu vaccine as soon as
possible because, as mentioned,
it takes 2 weeks for those protective
antibodies to actually develop.
The nasal spray is not effective.
You should get the flu shot
to be properly vaccinated.
The flu shot is designed yearly to
protect against the highest risk
and actively circulating
strains of influenza.
Herd immunity is the idea that when
most people get the flu vaccine,
it helps protect the population as a whole.
Children need to receive 2 flu shots
per the recommended schedule,
4 weeks apart if they have not
previously received the double vaccine.
Children 6 months through 8 years
getting vaccinated for the first time
and those who have only previously
gotten 1 dose of the vaccine
should get 2 vaccines
during the next flu season.
All children who have previously
gotten 2 doses of the vaccine
at any time only need 1 dose.
The first dose should be given as soon
as the vaccine becomes available.
In management in deciding how many
vaccines your pediatric patient will need,
you need to see, are they between
6 months and 8 years of age?
If so, the next step is have they
received 2 or more total doses
of any trivalent flu vaccine
prior to July 1st of 2016?
If "yes," they can just get 1 dose.
The second dose should be given at
least 28 days after the first dose.
And this first dose is going
to prime the immune system.
The second dose is what's actually
providing the immune protection.
Children who only get 1 dose,
but actually needed 2,
will have reduced or no protection
from a single dose of the flu vaccine.
So it's like they never got
their flu shot to begin with.
If the child needs 2 doses,
start the process early
since it will take 2 weeks
after the second dose
for the protection to actually begin.
And this will ensure that
the child is protected
before influenza starts
circulating in their community.
The flu virus is smart and sneaky,
and it poses a huge challenge.
It's always changing.
Both antigenic drift and antigenic
shift are terms used to describe ways
in which the flu virus changes over time.
A drift is a minor change,
and a shift is a major one.
While influenza viruses are changing
by antigenic drift all the time,
antigenic shift only happens occasionally.
Antigenic drift is a minor
change in the H and N proteins.
When the virus replicates, these
little point mutations occur,
but overall, the subtype remains the same.
When these minor changes
or mutations happen,
the virus looks a little bit
different to our immune system
and the antibodies created previously
to the flu virus or the flu vaccine
will no longer recognize the new virus.
This is continually happening.
The antibodies made to protect
you from another infection
are very specific to the 1 strain only,
and provide very limited protection in the
event you get sick with another strain.
This is why we need flu vaccines every year.
The new vaccine is going to have the new
changes from the new antigenic drifts.
This is in contrast to antigenic shift,
which is a major change
in the influenza virus.
This shift occurs, typically,
when the human flu virus
crosses with a flu virus that
usually affects animals,
such as birds or pigs, and involves
major changes in the H and N proteins.
When these viruses mutate, they
shift to create new subtypes,
and that's a different form that's
ever been seen in humans before.
This can happen in 3 ways.
The first, a human flu virus is going
to infect an animal, such as a pig.
The same pig also gets infected
by a flu virus from another
animal, such as the duck.
The 2 flu viruses can mix and mutate,
creating a completely new flu,
which can then spread back to humans.
The second way is a strain of bird
flu can pass directly to humans
without undergoing any type of mutation.
And the third way is a strain of bird flu
that's going to pass to another animal first,
and then be passed on to humans without
undergoing any type of mutation.