Diallo Mamadou B C, Anceno Alfredo J, Tawatsupa Benjawan, Houpt Eric R, Wangsuphachart Voranuch, Shipin Oleg V
WHO Collaborating Center for Water Supply and Waste Disposal, Environmental Engineering and Management, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand.
Sci Total Environ. 2008 Dec 15;407(1):223-32. doi: 10.1016/j.scitotenv.2008.09.034. Epub 2008 Oct 26.
A quantitative microbial risk assessment (QMRA) of Cryptosporidium, Giardia and diarrhegenic Escherichia coli (DEC) infection was performed using Monte Carlo simulations to estimate the human health risks associated with the use of canal water for recreational purposes, unrestricted and restricted irrigation in a tropical peri-urban area. Three canals receiving municipal, agricultural, and, predominantly, industrial wastewater were investigated. Identification of pathogenic protozoans revealed the major presence of Cryptosporidium hominis and both assemblages A and B of Giardia lamblia. The highest individual infection risk estimate was found to be for Giardia in an exposure scenario involving the accidental ingestion of water when swimming during the rainy season, particularly in the most polluted section, downstream of a large wholesale market. The estimated annual risks of diarrheal disease due to infection by the protozoan parasites were up to 120-fold greater than the reported disease incidence in the vicinity of the studied district and the entire Thailand, suggesting a significant host resistance to disease beyond our model's assumptions. In contrast, annual disease risk estimates for DEC were in agreement with actual cases of diarrhea in the study area.
采用蒙特卡罗模拟方法，对隐孢子虫、贾第鞭毛虫和致泻性大肠杆菌（DEC）感染进行了定量微生物风险评估，以估计在热带城郊地区将运河水用于娱乐目的、无限制和有限制灌溉所带来的人类健康风险。对三条接纳城市、农业（主要是工业）废水的运河进行了调查。对致病原生动物的鉴定显示，主要存在人隐孢子虫以及蓝氏贾第鞭毛虫的A群和B群。在涉及雨季游泳时意外摄入水的暴露情景中，尤其是在大型批发市场下游污染最严重的区域，发现贾第鞭毛虫的个体感染风险估计最高。原生动物寄生虫感染导致腹泻病的估计年风险比研究区域及整个泰国附近报告的疾病发病率高出多达120倍，这表明宿主对疾病具有显著的抵抗力，超出了我们模型的假设。相比之下，DEC的年疾病风险估计与研究区域腹泻的实际病例相符。
