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INTRODUCTION TO THE VFARS WORKSHOP
Citation:
Stelma Jr., G N. INTRODUCTION TO THE VFARS WORKSHOP. Presented at VFARs Workshop, Baltimore, MD, October 28-29, 2004.
Impact/Purpose:
Explore and support the best approaches for determining how, when, and for what pathogens, VFAR concepts can be used to identify pathogens that are hazardous to humans, in order to identify pathogens to nominate for the CCL process.
Description:
A 1996 amendment to the Safe Drinking Water Act requires the EPA to periodically develop a list of currently unregulated contaminants and select five contaminants for regulatory decisions every five years. The National Research Council (NRC) was enlisted to assist the Agency in developing processes to develop new Contaminant Candidate Lists and to prioritize contaminants. The NRC suggested the premise that the architectural and biochemical components of microorganisms that cause disease are structurally related and that structure-activity relationships of virulence genes (VFARs) can be used to predict virulence in microorganisms the way that quantitative structure-activity relationships of chemicals (QSARs) can be used to predict toxicity. If this premise holds up, EPA should be able to use VFARs to develop new Contaminant Candidate Lists (CCLs), prioritize the pathogens on the list and possibly even to identify currently unrecognized pathogens. There are, however, some challenges that must be overcome before VFARs can be used in decision making. For example, we do not know the extent to which the biological universe parallels the chemical universe; nor do we know the entire array of virulence factors, except for a few pathogens. Host susceptibility factors and the presence of unexpressed virulence genes in some microorganisms must also be considered. This workshop is being held to allow EPA to get the advice from experts in the field of microbial pathogenesis and virulence regarding the types of research that is needed to evaluate the usefulness of VFARs in the CCL process.