to review the scientific literature on vaccine safety. Two reports were issued (IOM, 1991, 1994). These reports contain a framework for causality assessment of vaccine adverse events.1 The reports addressed the vaccines covered by the VICP up to that point: diphtheria and tetanus toxoids and whole cell pertussis vaccine and other tetanus toxoid–containing vaccines; measles, mumps, and rubella (MMR) vaccines; Haemophilus influenzae type B vaccine; hepatitis B vaccine; and both inactivated and oral polio vaccines.2 The reports informed the secretary’s review of the Vaccine Injury Table. The reports have also been referenced extensively as a source of definitive scientific understanding of the evidence by Special Masters in decisions regarding injuries not listed on the Vaccine Injury Table.

The IOM was subsequently asked to review specific vaccine safety concerns in a series of reports requested by the CDC. These reports (IOM, 2001a,b, 2002a,b, 2003a,b, 2004a,b) included causality assessments similar to the previous IOM reports, but included other conclusions and recommendations regarding research, communications, and policy review.


In 2009 HRSA requested that the IOM convene a committee of experts to review the epidemiological, clinical, and biological evidence regarding adverse health events associated with specific vaccines covered by the VICP. The committee was charged with developing a consensus report with conclusions on the evidence bearing on causality and the evidence regarding the biological mechanisms that underlie specific theories for how a specific vaccine is related to a specific adverse event. The vaccines to be reviewed include varicella zoster vaccine, influenza vaccines (but not 2009 H1N1 vaccine), hepatitis B vaccine, human papillomavirus vaccine, tetanus-containing vaccines other than those containing the whole cell pertussis component, MMR vaccine, hepatitis A vaccine, and meningococcal vaccines. It is expected that the report will provide the scientific basis for review and adjudication of claims of vaccine injury by the VICP.

HRSA presented a list of specific adverse events for the committee to review (see Table 1-1). The selection criteria were described at the first committee meeting (Johann-Liang, 2009) as including the vast majority of adverse events in the claims for compensation. The committee added adverse events to the list if it identified epidemiologic studies or case reports


1 Adverse events are distinguished from adverse effects in that an event is something that occurs but may not be causally associated, whereas an adverse “effect” implies causation. All adverse effects are adverse events, but not all adverse events are adverse effects.

2 Vaccines are included in the VICP if they are recommended by the CDC for routine admin istration in children and are subject to an excise tax. Adults who experience an adverse reaction to one of these “childhood” vaccines are also covered by the program.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement