Pham-Duc Phuc, Nguyen-Viet Hung, Hattendorf Jan, Cam Phung Dac, Zurbrügg Christian, Zinsstag Jakob, Odermatt Peter
Center for Public Health and Ecosystem Research (CENPHER), Hanoi School of Public Health (HSPH), 138 Giang Vo, Hanoi, Vietnam.
BMC Public Health. 2014 Sep 20;14:978. doi: 10.1186/1471-2458-14-978.
Despite the potential health risks of wastewater and excreta use as fertiliser in agriculture, it is still widespread in Vietnam. However, the importance of diarrheal risk in adults' associated with the combined exposures to both excreta and wastewater use in agriculture is largely unknown. This study was carried out to determine diarrhoeal incidence and associated risk factors among the adult population exposed to wastewater and excreta used in agriculture in Hanam province, Vietnam.
An open cohort of 867 adults, aged 16-65 years, was followed weekly for 12 months to determine the incidence of diarrhoea. A nested case-control study was used to assess the risk factors of diarrhoeal episodes. Two hundred and thirty-two pairs of cases and controls were identified and exposure information related to wastewater, human and animal excreta, personal hygiene practices, and food and water consumption was collected.
The incidence rate of reported diarrhoea was 0.28 episodes per person-years at risk. The risk factors for diarrhoeal diseases included direct contact with the Nhue River water (odds ratio [OR] = 2.4, attributable fraction [AF] 27%), local pond water (OR = 2.3, AF 14%), composting of human excreta for a duration less than 3 months (OR = 2.4, AF 51%), handling human excreta in field work (OR = 5.4, AF 7%), handling animal excreta in field work (OR = 3.3, AF 36%), lack of protective measures while working (OR = 6.9, AF 78%), never or rarely washing hands with soap (OR = 3.3, AF 51%), use of rainwater for drinking (OR = 5.4, AF 77%) and eating raw vegetables the day before (OR = 2.4, AF 12%).
Our study shows that professional exposure to wastewater and excreta during agricultural activities are significantly contributing to the risk of diarrhoea in adults. The highest attributable fractions were obtained for direct contact with Nhue River and local ponds, handling practices of human and animal excreta as fertilisers, lack of protective measures while working and poor personal hygiene practices, and unsafe food and water consumption were associated with the risk of diarrhoeal episodes in adults. Improve personal hygiene practices and use of relevant treated wastewater and excreta as the public health measures to reduce these exposures will be most effective and are urgently warranted.
尽管将废水和粪便用作农业肥料存在潜在健康风险，但在越南这种做法仍然很普遍。然而，成人因农业中同时接触粪便和废水而导致腹泻风险的重要性在很大程度上尚不清楚。本研究旨在确定越南河南省接触农业中使用的废水和粪便的成年人群中的腹泻发病率及相关危险因素。
对867名年龄在16 - 65岁的成年人组成的开放队列进行为期12个月的每周随访，以确定腹泻发病率。采用巢式病例对照研究评估腹泻发作的危险因素。确定了232对病例和对照，并收集了与废水、人畜粪便、个人卫生习惯以及食物和水消费相关的暴露信息。
报告的腹泻发病率为每风险人年0.28次发作。腹泻疾病的危险因素包括直接接触泸江水（比值比[OR]=2.4，归因分数[AF]27%）、当地池塘水（OR = 2.3，AF 14%）、人粪便堆肥时间少于3个月（OR = 2.4，AF 51%）、在田间工作中处理人粪便（OR = 5.4，AF 7%）、在田间工作中处理动物粪便（OR = 3.3，AF 36%）、工作时缺乏保护措施（OR = 6.9，AF 78%）、从不或很少用肥皂洗手（OR = 3.3，AF 51%）、饮用雨水（OR = 5.4，AF 77%）以及前一天食用生蔬菜（OR = 2.4，AF 12%）。
我们的研究表明，农业活动期间职业性接触废水和粪便会显著增加成年人腹泻风险。与接触泸江和当地池塘水、人畜粪便作为肥料的处理方式、工作时缺乏保护措施以及个人卫生习惯差相关的归因分数最高，不安全的食物和水消费与成年人腹泻发作风险有关。改善个人卫生习惯以及使用经过处理的相关废水和粪便作为公共卫生措施以减少这些接触将最为有效，且迫切需要这样做。
