Mokhtar Amira B, Karanis Panagiotis, Schou Chad, Ahmed Shahira A
Department of Medical Parasitology, Faculty of Medicine, Suez Canal University, Ismailia 415221, Egypt; These authors have contributed equally to this work. E-mail:
Medical Faculty and University Hospital, University of Cologne, Cologne, Germany; Department of Basic and Clinical Sciences, University of Nicosia Medical School, 24005, CY-1700 Nicosia, Cyprus.
J Water Health. 2023 Sep;21(9):1325-1341. doi: 10.2166/wh.2023.179.
Blastocystis sp. is a common widely distributed gut protozoan, with water transmission identified as one of its transmission routes. This study aimed to investigate the effect of chlorine, ultraviolet (UV)-C, and microwave (MW) treatments on the in vitro viability of cysts of Blastocystis sp. Purified Blastocystis sp. cysts were molecularly subtyped. Viable cysts were subjected to different free chlorine concentrations (1, 2, and 4 ppm), different doses of UV-C (5.13, 10.26, 20.52, and 40.47 mJ/cm), and MW irradiation times (10, 15, 30, and 45 s). Viability reduction percentage, log inactivation, and micrometre-based optical microscopy examined cyst number and appearance after each disinfection trial. The three disinfectants' efficacy and application conditions were assessed. The analysed isolates of Blastocystis cysts were subtype 3, possessed varying sizes and shapes, but two identical genomes. The cysts of Blastocystis sp. were resistant to chlorine at all doses and exposure durations tested. UV-C at a dose of 40 mJ/cm and MW treatment for 15 s were able to completely disinfect the cysts. The MW was the most effective disinfectant against Blastocystis cysts based on all evaluated factors. MW irradiation is the most efficient water treatment method for eradicating Blastocystis cysts in an easy and safe manner.
芽囊原虫是一种广泛分布的常见肠道原生动物，水传播被确定为其传播途径之一。本研究旨在调查氯、紫外线-C（UV-C）和微波（MW）处理对芽囊原虫包囊体外活力的影响。对纯化的芽囊原虫包囊进行分子亚型分析。将活的包囊暴露于不同的游离氯浓度（1、2和4 ppm）、不同剂量的UV-C（5.13、10.26、20.52和40.47 mJ/cm²）以及MW照射时间（10、15、30和45秒）。在每次消毒试验后，通过活力降低百分比、对数灭活以及基于微米的光学显微镜检查包囊数量和外观。评估了这三种消毒剂的效果和应用条件。所分析的芽囊原虫包囊分离株为亚型3，具有不同的大小和形状，但有两个相同的基因组。在所有测试的剂量和暴露持续时间下，芽囊原虫包囊对氯具有抗性。剂量为40 mJ/cm²的UV-C和15秒的MW处理能够完全杀灭包囊。基于所有评估因素，MW是对抗芽囊原虫包囊最有效的消毒剂。MW照射是以简便且安全的方式根除芽囊原虫包囊的最有效水处理方法。
