Shepherd K M, Wyn-Jones A P
School of Health Sciences, The University, Sunderland, United Kingdom.
Appl Environ Microbiol. 1996 Apr;62(4):1317-22. doi: 10.1128/aem.62.4.1317-1322.1996.
Methods for the simultaneous detection of Cryptosporidium parvum oocysts and Giardia cysts from water are described and their relative recovery efficiencies are assessed for seeded samples of both tap and river water. Cartridge filtration, membrane filtration, and calcium carbonate flocculation were evaluated, and steps to optimize the concentration procedures were undertaken. Increasing centrifugation to 5,000 x g, coupled with staining in suspension, was found to increase the overall efficiency of recovery of both cysts and oocysts. Cartridge filtration for both cysts and oocysts was examined by use of 100-liter volumes of both tap and river water. Improvements in recovery were observed for Cryptosporidium oocysts after extra washes of the filters. Calcium carbonate flocculation gave the maximum recovery for both Cryptosporidium oocysts and Giardia cysts and for both water types. A variety of 142-mm membranes was examined by use of 10-liter seeded samples of tap and river water. Cellulose acetate with a 1.2-micron pore size provided the best results for Cryptosporidium oocysts, and cellulose nitrate with a 3.0-micron pore size did so for Giardia cysts.
描述了从水中同时检测微小隐孢子虫卵囊和贾第虫包囊的方法，并评估了其对自来水和河水加标样品的相对回收效率。对滤芯过滤、膜过滤和碳酸钙絮凝法进行了评估，并采取了优化浓缩程序的步骤。发现将离心速度提高到5000×g并结合悬浮染色可提高包囊和卵囊的总体回收效率。通过使用100升的自来水和河水对包囊和卵囊的滤芯过滤进行了检测。对滤芯进行额外冲洗后，微小隐孢子虫卵囊的回收率有所提高。碳酸钙絮凝法对微小隐孢子虫卵囊和贾第虫包囊以及两种类型的水都实现了最大回收率。通过使用10升的自来水和河水加标样品对多种142毫米的膜进行了检测。孔径为1.2微米的醋酸纤维素膜对微小隐孢子虫卵囊的检测效果最佳，孔径为3.0微米的硝酸纤维素膜对贾第虫包囊的检测效果最佳。
