论文部分内容阅读
[目的]探讨公共场所喷泉水嗜肺军团菌污染的影响因素,拟合logistic回归方程用于喷泉水嗜肺军团菌污染的预测,为预防和控制喷泉水军团菌污染提供科学依据。[方法]选择深圳市公共场所正常运行的80座喷泉作为研究对象,采用问卷调查、现场监测及实验室检测等方式收集相关数据。2015年7—12月收集50座喷泉(其中包括30座住宅小区喷泉和20座公共建筑周围的喷泉)相关资料,利用logistic回归法对可能影响喷泉水嗜肺军团菌污染的因素进行分析并建立回归模型,绘制受试者工作特征(ROC)曲线,确定喷泉水嗜肺军团菌污染的回归模型的最佳临界值。采用2016年1—7月收集的30座喷泉(其中包括20座住宅小区喷泉和10座公共建筑周围的喷泉)相关数据验证上述模型的准确率。[结果]单因素logistic回归分析发现,游离性余氯含量升高是嗜肺军团菌污染的保护因素(OR=0.986);运行年限的增加、喷泉水浊度升高、溶解性总固体含量升高是嗜肺军团菌污染的危险因素(OR=1.096、1.261、1.100)。经多因素logistic回归分析筛选出游离性余氯(OR=0.952,P<0.05)、浊度(OR=1.314,P<0.05)和溶解性总固体(OR=1.098,P<0.05)3个因素用于模型的拟合,其ROC曲线下面积为0.877(95%CI:0.808~0.997),该模型预测准确率为80.0%。[结论]logistic回归模型发现喷泉水游离性余氯、浊度和溶解性总固体是影响嗜肺军团菌污染的主要因素。该模型预测准确率较高,对公共场所喷泉水嗜肺军团菌污染的判断有一定的参考价值。
[Objective] To investigate the influencing factors of Legionella pneumophila contamination in fountains in public places and to fit the prediction of Legionella pneumophila contamination in fountain waters by fitting the logistic regression equation, so as to provide a scientific basis for prevention and control of Legionella pneumophila contamination. [Method] With the selection of 80 fountains in normal operation in public places in Shenzhen as the research object, the relevant data were collected by means of questionnaires, on-site monitoring and laboratory tests. From July to December 2015, 50 fountains (including 30 residential fountains and 20 public fountains) were collected and logistic regression analysis was used to analyze the factors that may affect Legionella pneumophila infection in fountain waters and to establish Regression model, plotting the receiver operating characteristic (ROC) curve, and determining the optimal cut-off value of the regression model for Legionella pneumophila contamination in the fountain water. The accuracy of the above model was verified using the data collected from January to July 2016 for 30 fountains, including fountains in 20 residential quarters and 10 fountains surrounding public buildings. [Results] Univariate logistic regression analysis showed that the increase of free residual chlorine was the protective factor of Legionella pneumophila contamination (OR = 0.986). With the increase of operating life, the turbidity of fountain water increased and the total soluble solid content increased High risk of Legionella pneumophila contamination (OR = 1.096,1.261,1.100). Multivariate logistic regression analysis screened out three factors of free residual chlorine (OR = 0.952, P <0.05), turbidity (OR = 1.314, P <0.05) and total dissolved solids For the model fitting, the area under the ROC curve is 0.877 (95% CI: 0.808-0.997). The prediction accuracy of this model is 80.0%. [Conclusion] Logistic regression model found that the free residual chlorine, turbidity and total dissolved solids of fountain water were the main factors affecting Legionella pneumophila pollution. The model has a high prediction accuracy and has certain reference value for judging the contamination of Legionella pneumophila in fountain water of public places.