Microbial Indicators of Marine Recreational Water Quality

Stephen B. Weisberg; Rachel T. Noble; John F. Griffith

doi:10.1128/9781555815882.ch22

Chapter 22 : Microbial Indicators of Marine Recreational Water Quality

Authors: Stephen B. Weisberg, Rachel T. Noble, John F. Griffith

Content Type: Reference

Publication Year: 2007

Category: Environmental Microbiology

Book DOI: 10.1128/9781555815882

Chapter DOI: 10.1128/9781555815882.ch22

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Abstract:

One concern with the use of Enterococcus as an indicator is that the epidemiology studies on which it was based were conducted at locations where sewage was the primary source of fecal contamination. Present methods to enumerate indicator bacteria in marine coastal waters rely on growth-based assays. Bacterial measurement methods include multiple-tube fermentation (MTF), membrane filtration (MF), and defined substrate (DS) methods. The survival of bacterial indicators in the ambient environment generally differs from that of viral pathogens, and thus, it may be more desirable to measure viral indicators directly. Two types of viral indicators are presently employed in some monitoring programs and epidemiology studies. The first is coliphages, which are viruses that infect coliform bacteria. The second group is enteric viruses, the measurement of which is only recently becoming cost-effective through use of PCR. The most likely coliphage group as a candidate water quality indicator is the F (male)-specific RNA (FRNA) coliphage, because it represents viruses similar in size, shape, and genetic makeup to human enteric viruses; it is more stable than human enteroviruses; and its concentrations in environmental waters have been reported to correlate with sewage contamination.

Citation: Weisberg S, Noble R, Griffith J. 2007. Microbial Indicators of Marine Recreational Water Quality, p 280-289. In Hurst C, Crawford R, Garland J, Lipson D, Mills A, Stetzenbach L (ed), Manual of Environmental Microbiology, Third Edition. ASM Press, Washington, DC. doi: 10.1128/9781555815882.ch22

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