Thermotolerant Coliforms Are Not a Good Surrogate for Campylobacter spp. in Environmental Water

Abstract

This study aimed to assess the importance of quantitatively detecting Campylobacter spp. in environmental surface water. The prevalence and the quantity of Campylobacter spp., thermotolerant coliforms, and Escherichia coli in 2,471 samples collected weekly, over a 2-year period, from 13 rivers and 12 streams in the Eastern Townships, Québec, Canada, were determined. Overall, 1,071 (43%), 1,481 (60%), and 1,463 (59%) samples were positive for Campylobacter spp., thermotolerant coliforms, and E. coli, respectively. There were weak correlations between the weekly distributions of Campylobacter spp. and thermotolerant coliforms (Spearman's coefficient ‫؍‬ 0.27; P ‫؍‬ 0.008) and between the quantitative levels of the two classes of organisms (Kendall tau-b correlation coefficient ‫؍‬ 0.233; P < 0.0001). Well water samples from the Eastern Townships were also tested. Five (10%) of 53 samples from private surface wells were positive for Campylobacter jejuni, of which only 2 were positive for thermotolerant coliforms. These findings suggest that microbial monitoring of raw water by using only fecal indicator organisms is not sufficient for assessing the occurrence or the load of thermophilic Campylobacter spp. Insights into the role of environmental water as sources for sporadic Campylobacter infection will require genus-specific monitoring techniques.

Campylobacteriosis in Urban versus Rural Areas: A Case-Case Study Integrated with Molecular Typing to Validate Risk Factors and to Attribute Sources of Infection

“…River water samples were collected from July, 2005 to October, 2007 [50] and processed as previously described [64]. From May 22, 2005 to October 16, 2007, 8 fresh, eviscerated whole chickens were purchased weekly in the different counties (one chicken per store).…”

Use of Amplified-Fragment Length Polymorphism To Study the Ecology of Campylobacter jejuni in Environmental Water and To Predict Multilocus Sequence Typing Clonal Complexes

“…jejuni isolates (n ϭ 950) were obtained from environmental water in a previous study (31). For isolates previously identified as Campylobacter spp., species identification was performed using a protocol adapted from the real-time PCR system of Chaban et al (6) (see the supplemental material).…”

Effect of Incubation Temperature on the Detection of Thermophilic Campylobacter Species from Freshwater Beaches, Nearby Wastewater Effluents, and Bird Fecal Droppings

“…Preenrichment at 37°C for 2 to 4 h before exposure to selective agents and incubation at 42°C has also been reported as a recovery method that resulted in an increased isolation of Campylobacter spp. from natural waters (33)(34)(35)37). Many previous studies on the occurrence of Campylobacter spp.…”

“…in aquatic environments, where species such as C. jejuni and C. lari could be present in small numbers (26,27). Another approach in water studies has been to have a 2-to 4-h preenrichment step at 37°C before subsequent enrichment at 42°C (33)(34)(35)(36)(37)(38). However, studies that used a preenrichment step of 37°C followed by enrichment at 42°C have often observed a low detection rate for C. coli, suggesting that a 42°C incubation temperature might not support the growth of stressed and injured cells of C. coli present in small numbers in water.…”