Hansard

On pronunciation, I shall take a different view just for the sheer devilment of it. I say thiomersal, and other members say thimerosal.

In this evening's debate, members have raised serious issues that require thoughtful responses. However, I should also place the matter in context by pointing out that certain vaccines are available for children, young children and babies to ensure that we address the difficult problem of whooping cough. In 1951, that disease took the lives of almost 100 young people; however, that number has been reduced to less than one death a year, thankfully. That substantial change has come about largely because of the vaccination programme that was established.

Members have also expressed concerns about the processes that the health department and the Scottish Executive follow in relation to vaccines. I want to explain those processes, because I am concerned that some of the coverage has either skated over, or deliberately misinterpreted the matter. Our advice is taken from the Committee on Safety of Medicines, the Joint Committee on Vaccination and Immunisation and, indeed, the World Health Organisation. I am reasonably content to take their guidance and to follow their judgments on many such issues, because they offer a level of expertise and knowledge that none of us here can aspire to.

Vaccines that contain thiomersal do have an impact; for example, they cause hypersensitivity reactions. Such reactions are a feature of most vaccination programmes, but the scale of the reaction in this case outweighs the vaccine's effectiveness in intervening to prevent whooping cough. It is a matter of record that the World Health Organisation's global advisory committee on vaccine safety has concluded that there is no evidence of toxicity in infants, children or adults who have been exposed to thiomersal in vaccines. I stress that expert advice makes it clear that the actual risks that are posed by vaccine-preventable diseases are significant compared with the theoretical risk from side effects of thiomersal. Some of the coverage has understated that in order to amplify some of the concerns about the impact of mercury in vaccines.

The motion notes that ethyl mercury is

"already banned in the United States of America".

That is not the case. In 1999, concern was expressed in the USA about exposure to mercury following immunisation, based on the realisation that the cumulative amount of mercury—the fact that it is the cumulative amount is important—in the US infant-immunisation schedule potentially exceeded the recommended threshold for methyl mercury. The cumulative amount of mercury that was used in the US infant-immunisation schedule was more than double the Scottish equivalent. That is why steps were taken to reduce the amount of mercury in the US infant-immunisation programme.

Thiomersal-containing vaccines are not banned in the United States. I will quote the most recent statement from the US Food and Drugs Administration's website:

"The FDA believes a recall of thimerosal-containing vaccines is not warranted because data show that these products are safe … The FDA does not believe that thimerosal-containing vaccines ‘present an imminent or substantial hazard to the public health' because available scientific data do not provide adequate evidence that exposure to thimerosal in vaccines can cause neurodevelopmental disorders."

That is an important statement in the context of some of the concerns that have been expressed during the debate and, in particular, in some newspaper coverage.

In discussing possible links with autism, we are dealing with a complex and sensitive area, and individuals suffering from autism and their families want to find explanations for the increase in autism during the past few years. Autism is a complex, debilitating and lifelong set of conditions that manifests itself in a variety of ways. The scientific evidence is clear. The Medical Research Council's review of autism research in December 2001 states:

"no evidence currently exists that proves a link between thiomersal-containing vaccines and autism, attention deficit-hyperactivity disorder, speech or language delays or other neuro-developmental disorders".

In short, no neuro-toxicity has been demonstrated as a result of the low level of thiomersal exposure from routine vaccination.

As a member of the Executive, I am concerned at the suggestion that we are in any way trying to conceal the facts. As recently as 14 January, the deputy chief medical officer issued a letter that included information for all health professionals to help them advise parents and patients on thiomersal in vaccines. It is at the heart of our policy to ensure that parents are given facts about vaccines in a dispassionate and accurate way, in order to enable them to make informed choices. A call has been made for that this evening, which I approve of.

That is related to the fact that the diphtheria, tetanus and whole-cell pertussis—DTwP—vaccine is recommended for babies at two, three and four months old. That recommendation is based on the best possible scientific and medical advice and on the fact that the vaccine provides much better protection than any other does. Cost is not a consideration—our decisions are based entirely on science and on what is best for our children.

As far as researching for the debate was concerned, it was very difficult to develop an awareness of the costs, as they have not featured in our consideration of the availability of vaccines. That reassured me with regard to questions that might have been asked, because it demonstrates that the principal assessment has been based on medical science and judgment, rather than on costs. That it was based on costs was a misconception that I wanted to lay to rest. I do not wish to underestimate the concerns, but it is important that people are informed.

On a Europe-wide strategy, we are—as a precautionary measure—seeking to phase out thiomersal-based vaccines over time. It is important that we remove mercury from vaccines. The Executive, the JCVI and the UK Medicines Control Agency endorse that recommendation, because it is sensible to reduce avoidable exposure to mercury over and above what would be consumed through food substances.

We are looking for a longer-term replacement, but we need to put that in the context of delivering, through research and through the development of medicines, equally effective protection against whooping cough. The primary objective of the vaccination programme is to prevent a return to the dark and deadly days of whooping cough in the late 1950s. That is why vaccine manufacturers are actively developing research programmes to eliminate, substitute or reduce thiomersal in vaccines. When such alternatives are licensed for use in the UK, we will seek the advice of the JCVI on their use in the childhood immunisation programme.