Vaccine safety policy analysis in three European countries: the case of thimerosal
Introduction
Increased societal concern regarding the safety of vaccines has had an impact on the risk tolerance of public health officials, parents, and medical professionals. Risks that were either unknown or accepted for years have come under new scrutiny and may result in new and changed perspectives. This has been due partly to the fact that effective immunization programs have markedly diminished the incidence of vaccine-preventable diseases in industrialized countries. As a result, there is a lower awareness of the risks associated with the diseases themselves and a greater prominence of the potential risks of adverse effects associated with the vaccines. Risk perceptions and the actions taken in response to real or perceived risks regarding vaccines can and do vary significantly among nations.
Due to the heightened awareness and concern over vaccine safety issues, immunization policymakers must carefully balance newly identified potential risks from vaccines with the actual risk of vaccine-preventable diseases. Concern regarding public reactions to new and often unverified safety issues may place pressure on policymakers and/or health care providers to act quickly in response to new information. However, this concern must be tempered by the caution required to assess the intended and unintended risks and benefits of any action undertaken. Ultimately, those responsible for public health must choose the most health protective course for the population at large.
Section snippets
Emergence of thimerosal as a concern
Thimerosal (referred to as thiomersal in Europe) is a mercury-containing compound widely used as a preservative in vaccines, eyedrops, and contact lens solutions. It has been used as an anti-microbial agent in vaccines for over 60 years. Thimerosal is very effective in preventing bacterial contamination, particularly in opened multi-dose vials, and, as a result, has prevented countless cases of death or illness.
The European Agency for the Evaluation of Medicinal Products (EMEA), the European
Methods
To analyze the responses to thimerosal in Europe, we conducted structured, face-to-face interviews with governmental and non-governmental officials in three European countries between December 2000 and January 2001. The European countries studied—France, Greece, and Ireland—were selected to represent a diverse cross-section across several parameters, including demographic and economic characteristics, type of health system, organization of immunization system, level and focus of previous
Background on thimerosal
Mercury exists in many forms. The preservative thimerosal contains ethyl mercury. However, little information is available on potential health risks from exposure to ethyl mercury. An early assessment of the health risks of all forms of mercury by the World Health Organization (WHO) found that insufficient information was available to perform risk calculations for human exposure to ethyl mercury compounds [4]. Little new information has become available since that time. However, the WHO in its
Perspective of three European countries regarding thimerosal
This section provides a brief background on the three European countries studied, including an overview of their health and immunization systems, and summarizes our findings related to each country's response to thimerosal in vaccines.
Summary
Unlike in the US, there was no significant response to thimerosal by immunization policy officials in any of the three European countries studied. The EMEA's recommendations stressed that vaccination should continue in accordance with existing national immunization schedules, but that whenever possible a preference for non-thimerosal containing vaccine be followed.
The most important reason for the lack of action in these European countries was that potential exposure to thimerosal was less than
Acknowledgements
Funding for this study was provided by the Program for Appropriate Technology in Health (PATH).
References (44)
- et al.
Impact of anti-vaccine movement on pertussis control: The untold story
Lancet
(1998) - et al.
Workshop group: Greece
Vaccine
(1995) - et al.
Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorders in children
Lancet
(1998) Drug-trial compensation demands in Ireland
Lancet
(2000)- EMEA, EMEA Public Statement on Thiomersal Containing Medicinal Products, July 8,...
- Le Secretaire d'Etat a la Santé Communique, Paris, France: Ministere de l'Emploi et de la Solidarite, October 1,...
- World Health Organization, Mercury, Environmental Health Criteria Document No. 1. Geneva, Switzerland,...
- Environmental Protection Agency, Mercury Study Report to Congress. Document No. EPA-452/R-97-007. Research Triangle...
- U.S. Food and Drug Administration, Action level for mercury in fish, shellfish, crustaceans, and other aquatic animals,...
- ATSDR, Toxicological profile for mercury. Atlanta, Georgia,...