AWWA PATH50795

This paper describes a generalization of the work conducted for International Life Sciences Institute (ILSI) during the evaluation of the microbial risk assessment Framework. In general, it was found that the ILSI Framework was a valuable tool in guiding the conduct of a quantitative risk assessment for microbial agents. Further, in contrast to the chemical-based framework, the ILSI Framework allows for the incorporation of disease specific epidemiological data. However, the strongest critique of the ILSI Framework was that it falls short of explicitly incorporating features of the disease transmission process that highlight the distinction between infectious disease risk and a more conventional static risk process. A risk assessment methodology consistent with the ILSI Framework for assessing health risks to exposure to pathogens within the environment is presented. This methodology incorporates a primary pathway that is based on the exposure to pathogens in the environment and a secondary pathway that assumes direct transmission from an infected individual to a susceptible individual. The methodology is demonstrated using rotavirus disease transmission as an example. Includes 16 references, tables, figure.