Vaccinations and autism: Is there a connection?
You read the headlines. You see the interviews with
parents. They claim vaccinations caused autism in
their children. But is what you hear and read true?
"Parents hear stories and get worried," says
David Zalut, MD, a family physician who meets
with concerned parents. "But, there is no medical
evidence vaccines cause autism."
Denise Bell, MD, FAAP, is a pediatrician who reminds
parents of the importance of childhood vaccinations.
"Some diseases can have serious complications
and may even result in death," explains Dr. Bell. "The
sooner children are exposed to the weakened viruses
and bacteria in vaccines, the sooner they will develop
antibodies to protect against future infections."
There are three common concerns parents have
when it comes to vaccinating their children. Drs. Zalut
and Bell explain the validity of them.
The MMR vaccine and autism
The MMR vaccine, which protects children from
measles, mumps and rubella, is given to children
between 12 and 15 months - about the same time
babies begin to develop speech and motor skills.
Because these are obvious developmental markers,
when they are delayed, or don't occur at all, parents
worry it's a sign of autism due to the vaccine.
Dr. Bell understands why parents are concerned,
but wants them to know vaccines do not cause autism.
"Parents want what is best for their children, and
when they see a delay, they are looking for answers
as to 'Why?' Parents may think there is a correlation
between the vaccine and autism, but there may have
been earlier signs of delays that were not noticed."
Dr. Bell also points out the medical study that
first noted a connection between the MMR vaccine
and autism has since been discredited as not valid
by its own authors.
Thimerosal and autism
Arguments say that thermerisol, a mercury-containing
preservative used in childhood vaccines, causes autism.
However, thimerosal was removed from almost all
vaccines since 2001, and autism rates have still risen.
The exception is the flu vaccine. Some multi-dose
preparations of the influenza vaccine contain small
amounts of thimerosal; however, thimerosal in vaccines
has not been shown to cause harm.
"The amount of thimerosal in the flu vaccine is so
small, you would get five times more mercury eating
a tuna fish sandwich than in one dose of the vaccine,"
says Dr. Bell.
Children receive multiple vaccinations
Years ago, our parents got the small pox vaccine.
That single dose of small pox vaccine contained more
antigens - bacteria and proteins - than all of the
childhood vaccines of today combined.
"Kids today are exposed to less antigens than our
parents were years ago," says Dr. Bell. If the argument
were true, there should be higher rates of autism in the
generations before ours; but there aren't.
"There are many complications from diseases children
can get when they are not vaccinated on the recommended
time schedule," says Dr. Zalut. "Vaccination
schedules have proven to be safe. When parents
request vaccinations be spaced out, there may be lags
in protection for children."
So why the rise in autism cases?
Though there is no clear definition of what causes
autism, some speculate cases have risen due to its
definition. In 1994, the definition of autism was
broadened to include disorders now referred to as
autism spectrum disorders. Since then, cases have
been on the rise.
Education and awareness of parents as well as
those who care for children, may also contribute
to the rise in autism cases.
Still, Dr. Zalut says your best source for information
is your doctor. "Leave the headlines to magazines," he
says. "Discuss your concerns and learn the facts from
your physician."