Reducing
and eliminating the diseases that vaccines prevent is one of the top
achievements in the history of public health. But
some how the number of anti vaccinators increased from the past.
Its mainly through the widespread of news
regarding misconceptions of vaccines.
The
widespread fear that vaccines increase risk of autism originated with
a 1997 study published by Andrew Wakefield, a British surgeon. The
article was published in the
Lancet,
a prestigious medical journal, suggesting that the measles, mumps,
rubella (MMR) vaccine was increasing autism in British children. But
later this paper was completely discredited due to serious procedural
errors. ts publication set off a panic that led to dropping
immunization rates. However
that went unnoticed by many as
usual and still
rumours continue to spread.
Vaccines
need additives to improve the way they work, increase their shelf
life and make them as safe and effective as possible. The three main
substances added to vaccines are:
-
adjuvants or enhancer– to make the vaccine more effective
-
stabiliser – to stop the vaccine deteriorating when it is exposed to changes in the environment, such as light and temperature
- preservatives– to increase the vaccine’s shelf life.
Any
licensed vaccine is rigorously tested across multiple phases of
trials before it is approved for use, and regularly reassessed once
it is on the market. Scientists are also constantly monitoring
information from several sources for any sign that a vaccine may
cause an adverse event. Most vaccine reactions are usually minor and
temporary, such as a sore arm or mild fever. In the rare event a
serious side effect is reported, it is immediately investigated. So
available vaccines remain safe.
Common
Myth is that: Vaccines can cause autism bacause
they contain
ingredients that are dangerous. The
most often blamed culprit is thimerosal.
Thimerosal,
which is approximately 50% mercury by weight, has been one of the
most widely used preservatives in multi-dose vaccines. It is
metabolized or degraded to ethylmercury and thiosalicylate.
Ethylmercury is an organomercurial that should be distinguished from
methylmercury, the chemical actually known to cause harm.
Methylmercury is the type of mercury found in certain kinds of fish.
At high exposure levels methylmercury can be toxic to people. But
over a lifetime, everyone is exposed to some methylmercury through
food and environment.
The
different type of mercury in thiomersal
has the ability to be metabolised at a faster rate and they get
excreted quickly from our body. Thus thiomersal
is less likely to produce harmful effects on the human body.
Thimerosal
is used to prevent the growth of microbes during the manufacturing
process..Thiomersal is more commonly used in mixed dose vaccines.
Live and single dose vaccines do not necessarily need agents
likeThimerosal. When each new needle is inserted into the multi-dose
vial, it is possible for microbes to get into the vial. The
preservative, thimerosal, prevents contamination in the multi-dose
vial when individual doses are drawn from it. Receiving a vaccine
contaminated with bacteria can be deadly.
In
developing countries like India, multi dose vaccines are still being
used at large as
these
countries cannot afford to make single dose vaccines and not to use
preservatives like thiomersal. The cost of producing single dose
vaccines and the need to refrigerate them for proper storage and
transport makes the use of thiomersal absolutely necessary. However,
USA and some countries have decreased the use of thiomersal
in
vaccines only as a precaution. But even in those countries, it’s
use has not been discontinued altogether.
Research
indicates there is no difference in the rates of autism between
vaccinated and unvaccinated children. While autism may seem more
common in recent years,
This is because the diagnosis of autism now includes children with
milder symptoms who would not have been included in the past. There
is also greater public awareness of autism, and more parents are
seeking help. Even
today the true causes of autism remain a mystery, but to the
discredit of the autism-vaccination link theory, recent studies
provides evidence that autism develops in utero, well before a baby
is born or receives vaccinations. There is no evidence of a link
between MMR vaccine and autism or autistic disorders. Still
anti-vaccine
ideologists uses
”thiomersal”
and “mercury poisoning” as their main weapon for propagating
base-less ideas and
creating alarm in minds of parents.
Another
myth is that Babies Immune system get overloaded with vaccines. Based
on the number of antibodies present in the blood, a baby would
theoretically have the ability to respond to around 10,000 vaccines
at one time. Even if all 14 scheduled vaccines were given at once, it
would only use up slightly more than 0.1% of a baby’s immune
capacity. And scientists believe this capacity is purely theoretical.
The immune system could never truly be overwhelmed because the cells
in the system are constantly being replenished. In reality, babies
are exposed to countless bacteria and viruses every day, and
immunizations are negligible in comparison.
WHO
has closely monitored scientific evidence relating to the use of
thiomersal as a vaccine preservative for over 10 years, in particular
through its independent expert advisory group, the Global Advisory
Committee on Vaccine Safety. The Committee has consistently reached
the same conclusion: there is no evidence to suggest that the amount
of thiomersal used in vaccines poses a health risk. Immunization with
thiomersal-containing multi-dose vaccines currently protects at least
64% of all infants and children against four diseases with high
mortality rates: diphtheria, tetanus, pertussis and Haemophilus
influenza type b. The use of thiomersal-containing vaccines to
protect against these diseases averted at least 1400000 child deaths
in 2010. Thiomersal-containing vaccines are being used in over 120
countries. Removing thiomersal completely from vaccines would require
either using alternative preservatives or using preservative-free
single dose vaccines exclusively. Alternatives would incur
significant costs for development and regulatory approval, thereby
limiting the ability to offer affordable vaccines.
Immunisation
is one of our most significant achievements. It saves around 3
million lives world-wide each year and helps to prevent outbreaks and
hospitalisations from vaccine-preventable diseases. As a parent its
your duty to protect your child by ensuring vaccines are given on
time. Vaccine-preventable diseases are still common in many
countries. Increased travel and immigration means the risks are real.
In
reality, the benefits of vaccination greatly outweigh the risk i.e.,
having a vaccination is much safer than not having one. They're not
100% effective in every child, but they're the best defence against
the epidemics that used to kill or permanently disable millions of
children and adults. Choosing to protect your child with vaccines is
also a choice to help protect your family, friends, and neighbors.
i.e. to get vaccinated means to protect ourselves and to protect
those around us. Successful vaccination programmes depend on the
cooperation of every individual to ensure the wellbeing of all. We
should not rely on people around us to stop the spread of disease;
we, too, must do what we can.
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