Wiggins B A
Department of Biology, James Madison University, Harrisonburg, Virginia 22807, USA.
Appl Environ Microbiol. 1996 Nov;62(11):3997-4002. doi: 10.1128/aem.62.11.3997-4002.1996.
Discriminant analysis of patterns of antibiotic resistance in fecal streptococci was used to differentiate between human and animal sources of fecal pollution in natural waters. A total of 1,435 isolates from 17 samples of cattle, poultry, human, and wild-animal wastes were obtained, and their ability to grow in the presence of four concentrations of five antibiotics (chlortetracycline, halofuginone, oxytetracycline, salinomycin, and streptomycin) was measured. When the resulting antibiotic resistance patterns were analyzed, an average of 74% of the known isolates were correctly classified into one of six possible sources (beef, chicken, dairy, human, turkey, or wild). Ninety-two percent of human isolates were correctly classified. When the isolates were pooled into four possible categories (cattle, human, poultry, and wild), the average rate of correct classification (ARCC) increased to 84%. Human versus animal isolates were correctly classified at an average rate of 95%. Human versus wild isolates had an ARCC of 98%, and cattle versus poultry isolates had an ARCC of 92%. When fecal streptococci that were isolated from surface waters receiving fecal pollution from unknown origins were analyzed, 72% of the isolates from one stream and 68% of the isolates from another were classified as cattle isolates. Because the correct classification rates of these fecal streptococci are much higher than would be expected by chance alone, the use of discriminant analysis appears to hold promise as a method to determine the sources of fecal pollution in natural waters.
采用判别分析法分析粪便链球菌的抗生素耐药模式，以区分天然水体中粪便污染的人类和动物来源。从牛、家禽、人类和野生动物粪便的17个样本中总共获得了1435株分离菌，并测定了它们在五种抗生素（金霉素、常山酮、土霉素、盐霉素和链霉素）的四种浓度下的生长能力。当对所得的抗生素耐药模式进行分析时，平均74%的已知分离菌被正确分类到六个可能的来源之一（牛肉、鸡肉、奶制品、人类、火鸡或野生动物）。92%的人类分离菌被正确分类。当将分离菌汇总为四个可能的类别（牛、人类、家禽和野生动物）时，正确分类的平均率（ARCC）提高到84%。人类与动物分离菌的正确分类平均率为95%。人类与野生动物分离菌的ARCC为98%，牛与家禽分离菌的ARCC为92%。当对从不明来源接受粪便污染的地表水中分离出的粪便链球菌进行分析时，一条溪流中72%的分离菌和另一条溪流中68%的分离菌被分类为牛分离菌。由于这些粪便链球菌的正确分类率远高于仅靠随机猜测所能达到的水平，判别分析法作为一种确定天然水体中粪便污染来源的方法似乎很有前景。
