Natural viruses for the monitoring of treatment processes - Executive Summary - Use of natural viruses in monitoring water treatment processes

Pathogenic viruses are a significant microbial hazard in the production of drinking water. Determining how well the treatment (stages) remove such viruses is therefore crucial. It is still currently not possible to routinely determine the removal of pathogenic viruses in full-scale drinking water treatment, because the concentrations of the pathogenic viruses present in the raw water are too small. Natural viruses however occur in very high concentrations in surface water. With these natural viruses it was possible to determine the virus removal rate over the total treatment train at two locations where drinking water is produced from surface water, and at two locations where bank filtrate is used. The natural viruses also revealed the virus removal in the different process stages. This study shows that the removal of viruses through physical processes in a full-scale water treatment plant can be rapidly and routinely measured through the use of the natural viruses. In this way, the microbial safety of drinking water can be far better demonstrated.

Interest: contain breakthrough of pathogenic viruses. Viruses are infectious in low numbers, and the presence of pathogenic viruses in drinking water is a health hazard for the consumer. It is therefore important that the water treatment processes sufficiently remove pathogenic viruses. But it is not possible to measure the removal of actually pathogenic viruses at a production location, because their concentrations in the raw water are very small. For this reason, an effective method is needed to reliably assess the removal of pathogenic viruses. Raw water contains significant quantities of natural viruses. Some of these natural viruses could possibly serve as process markers for the removal of pathogenic viruses.

Report – This research is described in the report Natuurlijke virussen om de verwijdering van virussen door zuiveringsprocessen te bepalen (BTO 2020.009). One application of natural viruses is also described in: Monitoring the integrity of reverse osmosis membranes using novel indigenous freshwater viruses and bacteriophages. (Hornstra et al, Environ. Sci.: Wat er Res. Technol. 2019).