Department of Civil and Environmental Engineering, University of California Davis, 1 Shields Avenue, Davis, CA, USA.
Effects of Etiological Agent and Bather Shedding of Pathogens on Interpretation of Epidemiological Data Used to Establish Recreational Water Quality Standards
Article first published online: 7 JAN 2009
© 2008 Society for Risk Analysis
Volume 29, Issue 2, pages 257–266, February 2009
How to Cite
Loge, F. J., Lambertini, E., Borchardt, M. A., Başağaoğlu, H. and Ginn, T. R. (2009), Effects of Etiological Agent and Bather Shedding of Pathogens on Interpretation of Epidemiological Data Used to Establish Recreational Water Quality Standards. Risk Analysis, 29: 257–266. doi: 10.1111/j.1539-6924.2008.01184.x
- Issue published online: 23 JAN 2009
- Article first published online: 7 JAN 2009
- indicator organisms;
- recreational water quality;
The overall goal of the study reported herein was to use techniques in the field of risk assessment (specifically a state-space population dynamic model of disease transmission within recreational waters) to explore the relative significance of (1) active shedding of microorganisms from bathers themselves, and (2) the type and concentration of etiological agent on the observed heterogeneity of the incidence of illness in epidemiological studies that have been used to develop ambient water quality criteria. The etiological agent and corresponding dose ingested during recreational contact was found to significantly impact the observed incidence of illness in an epidemiological study conducted in recreational water. In addition, the observed incidence of illness was found not to necessarily reflect background concentrations of indicator organisms, but rather microorganisms shed during recreational contact. Future revisions to ambient water quality criteria should address the etiological agent, dose, and the significance of microbial shedding relative to background concentrations of pathogens and indicator organisms in addition to the incidence of illness and concentration of indicator organisms. Without a quantitative assessment of these additional variables, study findings may potentially be site specific and not representative of the health risks associated with specific indicator concentrations in all recreational waters.