Drinking water is a potential means for transmission of the opportunistic pathogen Legionella pneumophila. The objective of this research was to document the occurrence of L. pneumophila from source water, partially treated water after conventional water treatment, and distribution water. Water samples were examined for L. pneumophila by direct fluorescent antibody (DFA) techniques and by SYBR Green based real-time multiplex PCR. Primers were designed to amplify a 16S product of 490 bp and a mip product of 290 bp within L. pneumophila. Sensitivity of culture methods and PCR was determined by percent recovery and by using serial dilutions of positive control DNA, respectively. Eighty percent of source water samples were positive for L. pneumophila by real-time PCR versus 100% positive by DFA for L. pneumophila. Twenty percent of GAC filter water samples were positive for L. pneumophila by real-time PCR versus 40% positive by DFA. Distribution water samples yielded mixed results. Twenty percent of biofilms from the distribution system were positive for L. pneumophila by real-time PCR. This project confirms the potential for human infection by L. pneumophila from distribution water within the study area. / Department of Biology

Thesis (M.S.)--University of Nevada, Reno, 2007. / "August, 2007." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (M.S.)--University of North Carolina Wilmington, 2008. / Vita. Title from PDF title page (viewed May 27, 2009) Includes bibliographical references (p. 52-54)

Thesis (doctoral)--Tübingen, 1933.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 187-191). Available also in a digital version from Dissertation Abstracts.

Thesis (doctoral)--Tübingen, 1933.

Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.

Thesis (M.S.)--University of North Carolina at Wilmington, 2006.

Thesis (M.S.)--Northern Michigan University, 2006. / Includes bibliographical references.

M. Tech. / Background: Waterborne disease contributes significantly to the total global disease burden. Populations in rural areas of South Africa depend on untreated waters for consumption and sanitation. Contamination of public water supplies by harmful bacteria such as pathogenic E. coli poses a major risk for public health. Ingestion of these pathogenic microorganisms present in the contaminated and untreated waters could cause infection, leading to systemic inflammatory responses manifested by the production of various proinflammatory cytokines. To date, there is no human system test available to detect whether water, following ingestion, would cause disease (i.e. whether the water is infectious). The current water testing methods only test for the presence of indicator organisms, such as faecal coliforms, total coliforms, and Escherichia coli. A reliable in-vitro bioassay that could assess whether the water would cause an inflammatory response was investigated in this study. Objectives: Pro-inflammatory cytokines and whole-blood have been used in similar studies to detect the inflammatory responses following exposure to specific stimulants such as dust, lipopolysaccharide (LPS), E. coli and various others. It has been reported that larger numbers of these contaminants induced higher levels of pro-inflammatory cytokine expression. This implies that the pro-inflammatory cytokine expression could be used as a marker of infection since, inflammation occurs in response to infection. Successful infection is thus necessary for inflammation to occur, and high levels of pro-inflammatory cytokine expression confirm that infection has occurred. Thus if pro-inflammatory cytokines could serve as indicators for infection, these cytokines could be used as indicators for bacterial pathogenicity of water.