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Thiomersal

Answer

As with all medicinal products, vaccine safety is continually monitored by the Medicines and Healthcare products Regulatory Agency (MHRA) with advice from independent experts. The United Kingdom's Committee on Safety of Medicines (CSM) and its expert working group on vaccine safety have thoroughly reviewed the safety of thiomersal-containing vaccines, including alleged links with neurodevelopmental disorders, and kept this under close review.In 2001, the CSM, now the Commission for Human Medicines, conducted a major review of the available evidence and has since then considered new data on a number of occasions as it has emerged. Following concerns in the United States of America (USA) about the possible toxicity of thiomersal-containing vaccines, the Department funded a study using the UK's general practice research database to investigate whether there is a relationship between the amount of thiomersal that an infant receives through vaccination at a young age and subsequent neurological disorders. Data from a study involving over a 100,000 UK children were considered by CSM in 2003. Further studies from Denmark involving almost half a million children and a study from the USA have also specifically investigated the suggested link between mercury-containing vaccines and autism. None of these studies have found any evidence of a causal association with subsequent neurodevelopment disorders, including autism.The advice of CSM stands that there is no evidence of harm from the very small quantities of thiomersal contained in some vaccines, with the exception of possible allergic reactions, typically skin rashes or local swelling at the site of injection. This view concurs with that of the World Health Organisation, the USA's Institute of Medicine and the European Medicines Agency. The balance of benefits and risks of thiomersal-containing vaccines remains overwhelmingly positive.None of the vaccines that are currently part of the recommended childhood immunisation programme contain mercury.

Secondary information

Type

Written question

Reference

442 c189-90W;442 c188-9W; 43205

Session

2005-06

Subjects

Children Vaccination Mercury

Link

View this Written question on www.publications.parliament.uk