Amoah Isaac Dennis, Reddy Poovendhree, Stenström Thor Axel
Institute for Water and Wastewater Technology, Durban University of Technology, P.O. Box 1334, Durban 4000, South Africa E-mail:
Department of Community Health Studies, Faculty of Health Sciences, Durban University of Technology, P.O. Box 1334, Durban 4000, South Africa.
Water Sci Technol. 2017 Nov;76(9-10):2389-2400. doi: 10.2166/wst.2017.324.
Soil-transmitted helminths (STHs) are a major health concern globally. Infection is mostly through contact with contaminated water, food or soil. Therefore to break the cycle of viable transmission STH eggs must be quantitatively detected in the environment. The effect of different reagents on the viability of Ascaris suum eggs during laboratory detection and quantification was assessed and different incubation solutions compared. Sulphuric acid gave a slightly higher recovery percentage of viable eggs (91.2%) than distilled water (90.0%) and 0.5% formalin (87.6%), although the difference was not statistically significant (p > 0.05). Acetoacetic acid, ethyl acetate, ammonium bicarbonate, zinc sulphate, magnesium sulphate and Tween 80, are reagents widely used in test protocols for the detection and quantification of STH eggs. Eggs were exposed to these reagents for different time durations. Acetoacetic acid resulted in the highest loss of viability (3.4 ± 0.7% viable), while magnesium sulphate resulted in the least effect (88.5 ± 1.2% viable). In conclusion the use of the selected reagents in the detection of these eggs was found to affect the viability of exposed eggs, especially during prolonged exposures. Therefore we recommended that eggs be exposed for ≤5 minutes, to reduce the risk of viability loss.
土源性蠕虫是全球主要的健康问题。感染主要通过接触受污染的水、食物或土壤。因此，为了打破可行的传播循环，必须在环境中对土源性蠕虫虫卵进行定量检测。评估了不同试剂在实验室检测和定量过程中对猪蛔虫卵活力的影响，并比较了不同的孵育溶液。硫酸的活卵回收率（91.2%）略高于蒸馏水（90.0%）和0.5%福尔马林（87.6%），尽管差异无统计学意义（p>0.05）。乙酰乙酸、乙酸乙酯、碳酸氢铵、硫酸锌、硫酸镁和吐温80是土源性蠕虫虫卵检测和定量试验方案中广泛使用的试剂。将虫卵暴露于这些试剂不同时间。乙酰乙酸导致的活力损失最高（活卵率为3.4±0.7%），而硫酸镁的影响最小（活卵率为88.5±1.2%）。总之，发现在检测这些虫卵时使用所选试剂会影响暴露虫卵的活力，尤其是在长时间暴露期间。因此，我们建议将虫卵暴露时间≤5分钟，以降低活力损失风险。
