Sampson Reyneé W, Swiatnicki Sarah A, Osinga Vicki L, Supita Jamie L, McDermott Colleen M, Kleinheinz G T
Department of Biology and Microbiology, University of wisconsin-Oshkosh, 800 Algoma Blvd., Oshkosh, WI 54904, USA.
J Water Health. 2006 Sep;4(3):389-93. doi: 10.2166/wh.2006.524.
A concern for public health officials is the presence of Escherichia coli (E. coli), an indicator of fecal contamination, in monitoring recreational waters. While E. coli is unlikely to cause disease in humans, its presence may indicate other more pathogenic microorganisms. Many factors can lead to changes in the survival of E. coli outside of the animal intestine and may affect the probability of colonizing a new host. Survival of bacteria in recreational water has been linked to water temperature, and most recently to the presence of sand on the beach. This project looked at the survival of an environmental E. coli isolate in lake water. Lake water microcosms were placed at 4, 10, 14, or 25 degrees C for up to 36 d and an enzyme-substrate test (Colisure, IDEXX Corp.) was used to determine the most probable number (MPN) of E. coli/100 ml water. E. coli numbers at all temperatures declined over the duration of the experiment. The decline was most pronounced at 14 degrees C and was slowest at 4 degrees C. The presence of sand in the microcosm increased the time that E. coli survived, regardless of temperature. From a beach management standpoint, these findings indicate that E.coli may persist in the environment in cooler water longer than in the warmer water encountered in late summer.
公共卫生官员关注的一个问题是，在监测娱乐用水时存在大肠杆菌（E. coli），它是粪便污染的一个指标。虽然大肠杆菌不太可能在人类中引发疾病，但其存在可能表明存在其他更具致病性的微生物。许多因素会导致大肠杆菌在动物肠道外的存活情况发生变化，并可能影响其定殖新宿主的概率。细菌在娱乐用水中的存活与水温有关，最近还与海滩上沙子的存在有关。该项目研究了一种环境大肠杆菌分离株在湖水中的存活情况。将湖水微宇宙置于4、10、14或25摄氏度下长达36天，并使用酶底物试验（Colisure，IDEXX公司）来确定每100毫升水中大肠杆菌的最可能数（MPN）。在整个实验过程中，所有温度下的大肠杆菌数量均下降。在14摄氏度时下降最为明显，在4摄氏度时下降最慢。微宇宙中沙子的存在增加了大肠杆菌存活的时间，与温度无关。从海滩管理的角度来看，这些发现表明，大肠杆菌在较冷的水中可能比在夏末遇到的温暖水中在环境中持续存在的时间更长。
