Is the MMR Vaccine Safe?

The MMR Vaccine has been integrated into childhood vaccination programmes since its introduction in the 1970s. Since then the treatment has successfully reduced the incidence of the highly contagious diseases the vaccine protects against, measles, mumps, and rubella.

At present the MMR vaccine is a vital component of the UK’s immunisation programme, and is offered to one your old children and to those just about to begin school. The injectable vaccine achieves a strong immunisation effect, and while its success can’t be doubted, more recently concerns have been raised about its safety. This article looks at where the concerns for the safety of the MMR vaccine come from and whether or not they have been substantiated.

Where do concerns about the MMR Vaccine come from?

The widespread concern about the safety of the MMR vaccine originated from a study reported in 1998 by Dr Andrew Wakefield which presented evidence that indicated that the vaccine caused autism and a bowel condition called Crohn’s Disease.

The publication of this report caused a media frenzy which fuelled a major health scare as many people believed that a vaccine given to every child in the UK could potentially cause one of two serious conditions. The consequences of this health scare are still being felt today as many people chose to forsake the MMR vaccine, and since then a number of outbreaks of the measles infection have been reported in the UK.

Since the initial report a number of investigations have been performed by independent health authorities and laboratories and journalists. Dr Wakefield was reported as having manipulated data that he reported in his publications amongst other ethical violations. The publication was retracted by the publishing journal, the Lancet once these facts were brought to light.

In 2010 Dr Wakefield was charged by the GMC with professional misconduct and can no longer practice medicine. A wealth of separate investigations have shown that there is no evidence to link the MMR vaccine with incidences of autism or Crohn’s disease. These studies have included large scale epidemiological investigations looking at large populations, and are therefore considered very accurate and reliable.

This incident has had a major impact on public health in the UK. As mentioned earlier, the report and subsequent media frenzy resulted in a sharp drop in vaccination against measles, mumps, and rubella, and the inevitable consequence of this was an increase in the incidences of the disease.

How safe is the MMR Vaccine?

While the autism scare was proven to be unfounded, there are still a number of risks posed by the MMR vaccine which can result in adverse reactions to the vaccine. Despite these the benefits of the vaccine far outstrip any potential harm they may cause, which is why it is still in widespread use today.

The MMR vaccine is composed of three separate vaccines, each targeting the virus of a specific illness (either measles, mumps, and rubella). It is delivered as a combination vaccine to spare children the pain of three separate injection, and each individual vaccine carries a risk of causing an adverse reaction.

About 1 in 10 of the children receiving the MMR vaccine develop a fever and rash anywhere between a week and 3 weeks after the initial injection. A small number (about 1 in 20) develop joint pain. This particular set of side effects is a consequence of the body reacting to the weakened version of the virus found in the vaccine. The body’s defences, dubbed the immune system, uses a higher than normal body temperature as a means of dealing with unwanted invaders, and this is why a mild fever is a relatively common side effect.

In the past the mumps element of the MMR vaccine was derived from a generation of weakened mumps viruses called the Urabe mumps strain. This particular strain was associated with extremely rare neurological disorders like aseptic meningitis, and as such its use was barred. The NHS stopped using MMR vaccines derived from the Urabe strain in the 90s, hover this strain is still used in other countries because it is significantly cheaper than alternatives.

The side effects of the MMR vaccine are rare and are far outweighed by the benefits of immunising a child against measles, mumps, and rubella. This is why the MMR vaccine is still widely used.

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