MMR vaccine





The MMR vaccine is a widely-used combined vaccine for measles, mumps and
rubella. It is generally administered to children around the age of 1 year,
with a booster dose before starting school (i.e. age 4/5)

Recently, controversy has arisen because some scientists claim to have found
evidence that, in a very small fraction of cases, the vaccine may be linked
to the development of autism. However, most scientific studies show that
there is no link -- the incidence of autism in children who have been
vaccinated is not significantly higher than that in those who have not been vaccinated.

The alarm was raised principally by a group lead by Dr. Andrew Wakefield
which was published in the respected journal The Lancet. Many lurid media
studies followed, leading to a widespread belief by the public that the
story was proven beyond doubt. Rebuttals by UK Government/UK National Health
Service (NHS) doctors and scientists were popularly disbelieved, partly
because Government pronouncements on safety had been widely discredited in
the 'Mad Cow' (Bovine Spongiform Encephalopathy, or BSE) affairs, and partly
because it was believed that the NHS could not afford to pay for the
separate vaccines. A sort of conspiracy theory type belief grew up which
later research cannot entirely dispel. Thus, many parents are worried by the
possibility, and would prefer to have the three vaccines administered
separately. In the UK, a large part of the controversy is that only the
combined vaccine is available on the UK National Health Service; those who
do not wish to have it given to their children must either have the separate
vaccines given privately, or not vaccinate their children at all.

Since the controversy began, there has been a noticeable increase in the
incidence of measles in the UK, which has been attributed to the lower rates
of vaccination. This drop in vaccination rates was one of the reasons why
the UK Government was against single vaccines - people are less likely to go
through three vaccinations than one single one. Other factors, such as the
danger caused by rubella to pregnant mothers and their children were also
posited as being relevant.

In the longer term, however, extensive studies of thousands of children in
various parts of the world (studies which are more extensive and detailed
that initially done by Dr. Wakefield's team) have failed to show the link
between autism and the MMR vaccine. Ironically, the publicity which
surrounded the controversy in the UK will doubtless lead to more cases of
the three diseases and birth defects occasioned by rubella both amongst the
unvaccinated population and even the vaccinated population, as the UK
populace are now at a level of vaccination where the protection offered by
herd immunity fails.