Some of the polio vaccine administered from 1955–1963 was contaminated with a virus, called simian virus 40 (SV40). The virus came from the monkey kidney cell cultures used to produce the vaccine. Most, but not all, of the contamination was in the inactivated polio vaccine (IPV). Once the contamination was recognized, steps were taken to eliminate it from future vaccines. Researchers have long wondered about the effects of the contaminated vaccine on people who received it. Although SV40 has biological properties consistent with a cancer-causing virus, it has not been conclusively established whether it might have caused cancer in humans. Studies of groups of people who received polio vaccine during 1955–1963 provide evidence of no increased cancer risk. However, because these epidemiologic studies are sufficiently flawed, the Institute of Medicine's Immunization Safety Review Committee concluded that the evidence was inadequate to conclude whether or not the contaminated polio vaccine caused cancer. In light of the biological evidence supporting the theory that SV40-contamination of polio vaccines could contribute to human cancers, the committee recommends continued public health attention in the form of policy analysis, communication, and targeted biological research.

Contents

• THE NATIONAL ACADEMIES
• IMMUNIZATION SAFETY REVIEW COMMITTEE
• REVIEWERS
• Foreword
• Acknowledgments
• Executive Summary
  • ABSTRACT
  • THE FRAMEWORK FOR SCIENTIFIC ASSESSMENT
  • SCIENTIFIC ASSESSMENT
  • SIGNIFICANCE ASSESSMENT
  • RECOMMENDATIONS FOR PUBLIC HEALTH RESPONSE
  • REFERENCES
• Immunization Safety Review: SV40 Contamination of Polio Vaccine and Cancer
  • THE CHARGE TO THE COMMITTEE
  • THE STUDY PROCESS
  • THE FRAMEWORK FOR SCIENTIFIC ASSESSMENT
  • UNDER REVIEW: SV40 CONTAMINATION OF POLIO VACCINE AND CANCER
  • SCIENTIFIC ASSESSMENT
  • SIGNIFICANCE ASSESSMENT
  • RECOMMENDATIONS FOR PUBLIC HEALTH RESPONSE
  • SUMMARY
• REFERENCES
• Appendix A Committee Recommendations and Conclusions from Previous Reports
• Appendix B Public Meeting Agenda July 11, 2002
• Appendix C Chronology of Important Events Regarding Vaccine Safety

Support for this project was provided by the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases of the National Institutes of Health as part of a National Institutes of Health Task Order No. 74. The views presented in this report are those of the Institute of Medicine Immunization Safety Review Committee and are not necessarily those of the funding agencies.

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.