Ehlers M M, Grabow W O K, Pavlov D N
Department of Medical Virology, University of Pretoria/NHLS, Pretoria 0001, South Africa.
Water Res. 2005 Jun;39(11):2253-8. doi: 10.1016/j.watres.2005.04.014.
Enteric viruses have been detected in many drinking water supplies all over the world. A meaningful number of these supplies were treated and disinfected according to internationally acceptable methods. In addition, counts of bacterial indicators (coliform bacteria and heterotrophic plate count organisms) in these water supplies were within limits generally recommended for treated drinking water and these findings have been supported by epidemiological data on infections associated with drinking water. The shortcomings of conventional treatment methods and indicator organisms to confirm the absence of enteric viruses from drinking water, was generally ascribed to the exceptional resistance of these viruses. In this study, the prevalence of enteroviruses detected from July 2000 to June 2002 in sewage, river-, borehole-, spring- and dam water as well as drinking water supplies treated and disinfected according to international specifications for the production of safe drinking water was analysed. A glass wool adsorption-elution technique was used to recover viruses from 10--20 l of sewage as well as environmental water samples, in the case of drinking water from more than 100 l. Recovered enteroviruses were inoculated onto two cell culture types (BGM and PLC/PRF/5 cells) for amplification of viral RNA with nested-PCR being used to detect the amplified viral RNA. Results from the study demonstrated the presence of enteroviruses in 42.5% of sewage and in 18.7% of treated drinking water samples. Furthermore, enteroviruses were detected in 28.5% of river water, in 26.7% of dam/spring water and in 25.3% of borehole water samples. The high prevalence of coxsackie B viruses found in this study suggested, that a potential health risk and a burden of disease constituted by these viruses might be meaningful. These findings indicated that strategies, other than end-point analysis of treated and disinfected drinking water supplies, may be required to ensure the production of drinking water that does not exceed acceptable health risks. More reliable approaches to ensure acceptable safety of drinking water supplies may be based on control by multiple-barrier principles from catchment to tap using hazard assessment and critical control point (HACCP) principles.
世界各地许多饮用水供应中都检测到了肠道病毒。其中相当数量的供水按照国际认可的方法进行了处理和消毒。此外，这些供水中的细菌指标（大肠菌群和异养平板计数生物）数量在通常推荐的处理后饮用水限量范围内，这些发现得到了与饮用水相关感染的流行病学数据的支持。传统处理方法和指示生物在确认饮用水中不存在肠道病毒方面的缺点，通常归因于这些病毒具有超强的抵抗力。在本研究中，分析了2000年7月至2002年6月期间在污水、河水、井水、泉水、坝水以及按照国际安全饮用水生产规范进行处理和消毒的饮用水供应中检测到的肠道病毒的流行情况。采用玻璃棉吸附 - 洗脱技术从10至20升污水以及环境水样中回收病毒，对于饮用水则从超过100升的水样中回收。将回收的肠道病毒接种到两种细胞培养类型（BGM和PLC/PRF/5细胞）中以扩增病毒RNA，采用巢式PCR检测扩增后的病毒RNA。研究结果表明，42.5%的污水样本和18.7%的处理后饮用水样本中存在肠道病毒。此外，在28.5%的河水样本、26.7%的坝水/泉水样本和25.3%的井水样本中检测到了肠道病毒。本研究中发现柯萨奇B病毒的高流行率表明，这些病毒构成的潜在健康风险和疾病负担可能相当大。这些发现表明，除了对处理和消毒后的饮用水供应进行终点分析之外，可能还需要其他策略来确保生产出健康风险不超过可接受水平的饮用水。确保饮用水供应可接受安全性的更可靠方法可能基于从集水区到水龙头采用危害评估和关键控制点（HACCP）原则的多屏障原则进行控制。
