SURVIVAL OF CAMPYLOBACTER JEJUNI AND ESCHERICHIA COLI IN GROUNDWATER DURING PROLONGED EXPOSURE TO LOW TEMPERATURES

Authors: Cook, Kimberly - Kim; Bolster, Carl

Submitted to: American Society for Microbiology
Publication Type: Abstract Only
Publication Acceptance Date: 2/17/2006
Publication Date: 5/22/2006
Citation: Cook, K.L., Bolster, C.H. 2006. Survival of campylobacter jejuni and escherichia coli in groundwater during prolonged exposure to low temperatures. American Society for Microbiology. (ISBN 1-55581-389-5)

Interpretive Summary:

Technical Abstract: Laboratory microcosm experiments were performed to compare the survival behavior of Campylobacter jejuni (C. jejuni), a leading cause of human gastroenteritis worldwide, and Escherichia coli (E. coli), a commonly used bacterial indicator of fecal contamination. Survival studies were carried out by incubating filter-sterilized groundwater and de-ionized water with either C. jejuni (1.8 ± 1.1 X 107 cells ml-1) or E. coli (7.1 ± 3.3 X 106 cells ml-1) for 300 days at 4 ºC. Groundwater was collected from three locations in south central Kentucky and nutrient analysis on the samples showed variations in nitrogen and dissolved organic carbon (DOC) concentrations. On days 0, 1, 2, 7, 14, 21 and periodically over the next 300 days, samples were taken for culturable cell counts (C. jejuni plated onto trypicase soy agar with 5% sheeps blood; E. coli plated onto LB agar), total cell counts (acridine orange, AO), and molecular analysis (quantitative, real-time PCR analysis, QRT-PCR). For all microcosms, total cell numbers, as measured by AO or QRT-PCR, did not change significantly for E. coli or C. jejuni during the 300-day experiment. Culturable cell numbers for C. jejuni decreased below detection limits (50 to 60 cells mL-1) in all microcosms within 90 days. In contrast, E. coli cells remained culturable in all water samples for greater than 250 days. Survival of C. jejuni was greatest in the microcosm with the highest DOC (4 mg/L) while E. coli survival was highest in water with the highest total dissolved nitrogen (11.5 mg/L). The average time required for 90 % die-off in groundwater microcosms was 19 ± 5 days for C. jejuni and 131 ± 39 days for E. coli. These results suggest that the survival profile (in terms of rate of die-off and nutrient conditions required for survival) for C. jejuni is significantly different from that of E. coli.