School of Biological, Earth and Environmental Science (BEES), University College Cork, Cork, Ireland; Environmental Research Institute, University College Cork, Cork, Ireland.
Irish Centre for Research in Applied Geosciences, University College Dublin, Dublin, Ireland; Environmental Sustainability and Health Institute (ESIH), Technological University Dublin, Ireland.
Water Res. 2020 Jun 1;176:115726. doi: 10.1016/j.watres.2020.115726. Epub 2020 Mar 18.
Cryptosporidiosis is one of the leading causes of diarrhoeal illness and mortality induced by protozoan pathogens worldwide. As a largely waterborne disease, emphasis has been given to the study of Cryptosporidium spp. in surface waters, readily susceptible to pathogenic contamination. Conversely, the status of Cryptosporidium in potable groundwater sources, generally regarded as a pristine and "safe" drinking-water supply owing to (sub)-soil protection, remains largely unknown. As such, this investigation presents the first literature review aimed to ascertain the global prevalence of Cryptosporidium in groundwater supply sources intended for human consumption. Thirty-seven peer-reviewed studies were identified and included in the review. Groundwater sample and supply detection rates (estimated 10-20%) indicate Cryptosporidium is frequently present in domestic groundwater sources, representing a latent health concern for groundwater consumers. Specifically, sample (10.4%) and source (19.1%) detection rates deriving from comprehensive "temporal" investigations are put forward as representative of a contamination 'baseline' for Cryptosporidium in 'domestic' groundwater supplies. Proposed 'baseline' prevalence figures are largely applicable in preventive risk-based catchment and groundwater quality management including the formulation of Quantitative Microbial Risk Assessment (QMRA). Notwithstanding, a large geographical disparity in available investigations and lack of standardized reporting restrict the transferability of research findings. Overall, the mechanisms responsible for Cryptosporidium transport and ingress into groundwater supplies remain ambiguous, representing a critical knowledge gap, and denoting a distinctive lack of integration between groundwater and public-health sub-disciplines among investigations. Key recommendations and guidelines are provided for prospective studies directed at more integrative and multi-disciplinary research.
隐孢子虫病是由原生动物病原体引起的全球腹泻病和死亡率的主要原因之一。作为一种主要的水传播疾病，人们已经对地表水中的隐孢子虫属进行了大量研究，这些水很容易受到病原体的污染。相反，由于（亚）土壤的保护，饮用水源中的隐孢子虫状况，通常被认为是原始的和“安全”的饮用水供应，在很大程度上仍然未知。因此，本研究首次进行了文献综述，旨在确定用于人类消费的地下水供应源中隐孢子虫的全球流行率。确定了 37 项同行评审研究，并将其纳入综述。地下水样本和供应检测率（估计为 10-20%）表明，隐孢子虫经常存在于家庭地下水源中，这对地下水消费者构成了潜在的健康威胁。具体而言，从全面的“时间”调查中得出的样本（10.4%）和来源（19.1%）检测率被提出作为“家庭”地下水供应中隐孢子虫污染的“基线”的代表性数据。提出的“基线”流行率数据在预防性基于风险的集水区和地下水质量管理中（包括制定定量微生物风险评估 (QMRA)）具有广泛的适用性。然而，现有调查的地理差异很大，缺乏标准化报告，限制了研究结果的可转移性。总体而言，隐孢子虫进入地下水供应的传输和进入机制仍不清楚，这代表了一个关键的知识空白，并表明调查中地下水和公共卫生子学科之间缺乏独特的整合。为了进行更具综合性和多学科性的研究，本研究提供了未来研究的关键建议和指导方针。
