Shrestha S, Haramoto E, Shindo J
Interdisciplinary Centre for River Basin Environment, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Kofu, Yamanashi, Japan.
J Appl Microbiol. 2017 Nov;123(5):1321-1334. doi: 10.1111/jam.13573. Epub 2017 Oct 10.
To assess diarrhoeal risks from enteropathogenic Escherichia coli, Giardia and Cryptosporidium from consuming raw spinach, cabbage, carrots and tomatoes in Kathmandu Valley, Nepal.
The annual infection risk was quantified using the probabilistic Quantitative Microbial Risk Assessment approach, which considered 12 vegetable washing combinations. A new model was used to estimate dose of pathogens per exposure comprising parameters such as pathogen concentration in vegetable wash water before selling and eating, vegetable consumption rate, remaining pathogen ratio after washing, remaining water on vegetables after washing and water treatment removal efficiency. When all washing combinations were considered, high infection risks above the acceptable level of -4 log infection per person per year were obtained, whereas the risk was reduced when other sources excluding river water were used. Assuming use of water treated with ceramic filters by all consumers, a 0-2 log reduction in the estimated risks was obtained, which was insufficient to achieve the required risk level.
High risk of diarrhoea prevails among raw vegetable consumers in the valley.
It is needed to protect vegetable washing water sources and establish advanced water treatment methods to achieve the required level of public health risk.
评估在尼泊尔加德满都谷地食用生菠菜、卷心菜、胡萝卜和西红柿感染致病性大肠杆菌、贾第虫和隐孢子虫而导致腹泻的风险。
采用概率性定量微生物风险评估方法对年感染风险进行量化，该方法考虑了12种蔬菜清洗组合。使用一种新模型来估计每次暴露的病原体剂量，该模型包含诸如销售和食用前蔬菜清洗水中的病原体浓度、蔬菜消费率、清洗后残留病原体比例、清洗后蔬菜上残留的水量以及水处理去除效率等参数。当考虑所有清洗组合时，获得的感染风险高于每人每年可接受的-4 log感染水平，而当使用除河水以外的其他水源时，风险会降低。假设所有消费者都使用陶瓷过滤器处理过的水，估计风险可降低0 - 2 log，但这不足以达到所需的风险水平。
该谷地生食蔬菜的人群中腹泻风险很高。
需要保护蔬菜清洗水源并建立先进的水处理方法，以达到所需的公共卫生风险水平。
