Immunizations by Christina Callas and Dr. Laura Chiel.
Learning Objectives.
By the end of this video the viewer
will be able to understand the impact of childhood vaccines
on disease incidence and morbidity,
describe how immunizations work, explain which vaccines
are given at each well-child check,
recognize special circumstances that
affect the vaccine schedule.
At the time of this publication the COVID-19 vaccine
was under review for full authorization
for pediatric patients.
We will not be covering the COVID-19 vaccine in this video.
But please visit the CDC website for the most up to date
information to help inform patients and families.
Introduction.
In the United States, vaccinations
begin within hours of birth and continue through childhood,
adolescence, and adulthood.
Childhood immunization has been one
of the most successful medical interventions for preventing
certain illnesses.
According to the CDC, diseases such as varicella, diphtheria,
Haemophilus influenza measles, mumps, rubella, and polio
have all seen over 95% decreases in disease incidence
with the introduction of vaccines.
How Vaccines Work.
In general, a vaccine is comprised
of antigens that are recognized and digested by macrophages.
Helper T cells recognize the antigen
on the surface of the macrophage,
and they activate the other immune cells, such as B cells
and cytotoxic T cells.
Cytotoxic T cells will destroy any cell with the antigen.
B cells develop into plasma cells
that will produce antibodies that bind the antigen
and mark the cell for destruction.
Some become memory T or B cells that
will be activated if the body is exposed again
to that antigen. In vaccines containing capsular
polysaccharides, such as conjugate vaccines,
a T cell independent B cell response is elicited.
There are multiple types of vaccines
you should be familiar with.
Live attenuated vaccines contain weakened live pathogens
and cannot be given to children with immunodeficiency.
Inactivated vaccines contain killed or inactivated
viruses or bacteria.
Conjugate vaccines combat bacteria
with polysaccharide capsules.
Polysaccharide antigens produce a weak immune response
so they are conjugated to a protein carrier
to enhance the immune response.
Toxoid vaccines contain weakened toxins
absorbed to aluminum or calcium salts
to enhance the immune response.
Subunit vaccines contain only antigens
from the pathogen, which leads to fewer side effects but also
a weaker immune response.
While vaccines can cause side effects, most of these
are mild, such as local redness or soreness, fussiness,
and/or low grade fever, and resolve in a couple of days.
There are a few conditions and contraindications,
such as severe allergic reaction,
that would preclude a child from receiving a specific vaccine.
But this is beyond the scope of this video.
Schedule.
Oftentimes in the clinic or on an exam you'll
be presented with a patient at her well-child visit
and may be asked which vaccine she is due for today.
In these cases, it is helpful to break down vaccines
by the age they are given.
There are nuances to the vaccine schedule,
and some vaccines can be given over a range of months.
A detailed vaccination schedule for infants and young children
can be found on the CDC or AAP website.
For the purposes of this video, we
will cover the basic timetable for a healthy child,
but it is important to confirm the timetable
of the clinic you practice in.
Additionally, children may require
special vaccines or early vaccination if traveling.
It is important to ask about travel,
and consult the CDC guidelines to ensure proper vaccination.
At birth, children will receive their first dose of hepatitis B
vaccine.
While not a vaccine, you should also
remember that all newborns receive a vitamin K
shot to prevent bleeding and erythromycin
ointment to prevent blindness from gonorrhea and chlamydia.
At the two month visit, an infant
may receive six vaccines.
They can get the second dose of hepatitis B
if not given earlier.
They will also be due for their first doses of DTaP,
diphtheria, tetanus, and acellular pertussis,
Haemophilus influenza type B, or H. Flu, pneumococcal conjugate
or PCV13, inactivated polio, and rotavirus.
Remember, not all vaccines are shots.
Rotavirus is an oral solution.
At four months, they will receive five vaccines.
Infants get their second dose of DTap, H. Flu, PCV13,
inactivated polio and rotavirus vaccines.
At the six month visit, infants get the third dose
of hepatitis B, DTaP, H. Flu, PCV13, inactivated polio
and rotavirus.
At six months, they can also receive their first dose
of the influenza vaccine.
Of note, children need a second dose at a minimum of four weeks
after they receive the first dose of the influenza vaccine.
After that they can receive the influenza vaccine annually.
A 12-month-old child will receive
their fourth and final dose of the H. Flu vaccine and PCV13.
Infants now need their first dose of MMR
or measles, mumps, rubella, varicella and hepatitis
A vaccines.
At the 15 month visit, an infant can receive the fourth DTaP
vaccine.
At 18 months, children can receive their second dose
of hepatitis A vaccine if the first dose was given
at least six months prior.
Between four and six years old, children
receive final doses of DTaP, inactivated polio, MMR,
and varicella.
Vaccines for older children include
meningococcal, Tdap or tetanus, diphtheria,
and acellular pertussis, and human papillomavirus
or HPV vaccines.
Between 11 and 12 years old, adolescents
receive their first dose of those three vaccines.
Of note, if the first HPV dose is given before age 15,
the series consists of two doses separated by 6 to 12 months.
The first dose can be initiated as early as nine years of age.
If the series is initiated at age 15 or older,
the teenager must receive three doses.
The second dose should be given four weeks after the first dose
and the third dose should be scheduled six
months after the first dose.
At 16 years old, teenagers receive the second dose
of the meningococcal vaccine.
Special Circumstances.
There are many special circumstances
that affect the vaccine schedule and we will cover only a few
of them here.
For example, children with sickle cell disease
or anatomic or functional asplenia,
HIV, or immunodeficiency, require
additional immunizations.
If you are seeing a child in clinic
with any of these conditions, or other chronic conditions,
you can refer to the vaccine schedule
for a specific guidelines.
One vaccine recommended for only some children
is a pneumococcal polysaccharide vaccine or PPSV23.
This vaccine should be administered for children
with a variety of conditions, including
chronic heart disease, chronic lung disease, or diabetes.
Once over the age of two, a child
with any of these conditions should
receive one dose of PPSV23 at least eight weeks
after a previous PCV13 dose.
Children with sickle cell disease, asplenia, HIV,
renal failure, malignancies, or children
treated with immunosuppressive drugs,
should also receive one dose at least eight weeks after PCV13,
in addition to a second dose of PPSV23 five years later.
Another special circumstance concerns
the meningococcal vaccine in children
with sickle cell disease, anatomic or functional
asplenia, or HIV.
You can reference the CDC or AAP website
for the recommended formulations and timetable, in addition to
confirming with the clinic you are working in.
Summary.
In summary, immunization has successfully
reduced the rates of many childhood illnesses.
Vaccines work to provoke an immune response in order
to prepare the body for exposure to very serious pathogens.
The vaccine schedule provides detailed information
about timing and doses of each vaccine for your patients.
During your clinical years you may
encounter a patient or a family who
has concerns or questions about vaccines.
It is important to try to understand
the concerns of families who do not
wish to vaccinate their children and engage
in respectful conversation about vaccination at every visit.
There are many helpful resources on the CDC website for you,
the provider, and the patient.
These include handouts on how vaccines work,
how they are tested for safety, the childhood vaccine
schedule, specific vaccine information sheets, and more.
Thank you for watching this video on immunizations.