Link to home

Water mediated virus transmission: sources, detection and inactivation

Maja Ravnikar: National Institute of Biology

<div>Environmental waters constitute a potential source of plant viruses. In this study we aimed to confirm if effluents from waste water are also home for plant viruses and if these remain infective, even after their trip through the wastewater plant. In order to detect the low virus concentrations present in water, we used either an efficient concentration system based on CIM monolithic chromatography or an easy-to-use tangential filtration system, Aquafilter. For virus detection after concentration, we used the most sensitive molecular method, quantitative PCR (qPCR). The integrity of the plants viruses was confirmed using transmission electron microscopy (TEM). The infectivity of plant viruses such as Pepper Mild Mottle virus and Tomato Mosaic Virus in concentrated water samples was confirmed by inoculation of test plants. To obtain a wider picture of the viral composition, we also analyzed the metagenome (Virome) of such samples using high throughput sequencing, which allowed us to find new viruses in the aqueous environment from where the samples were collected. Wastewater effluents are used as irrigation waters in many countries, where due to climate conditions, water is scarce. From our findings it is clear that a safe recycling of such waters would require methods that are able to inactivate viruses in water environment in an efficient and cost effective manner. We have tested the ability to inactivate viruses of two physical treatments, hydrodynamic cavitation and plasma. Both methods efficiently inactivated two model viruses (MS2 bacteriophage and Potato virus Y) in water, reaching up to 4 log reductions of the viral infectivity in the case of MS2, and showing up as two promising options to inactivate virus in water samples.</div>