Evaluation of the suitability of pepper mild mottle virus (PMMoV) as an indicator virus for water safety and quality

Wastewater pollution is one of the main causes of waterborne diseases (e.g., diarrheal diseases) because wastewater commonly contains a wide range of pathogenic microorganisms, notably human enteric viruses. Monitoring multiple pathogenic viruses in waters simultaneously is impractical and expensive, so monitoring through virus indicators is essential to ensure water safety and quality. Recently, pepper mild mottle virus (PMMoV) was found as one of the most prevalent viruses in the human gut microbiota and consistently present at high concentrations in human feces and domestic wastewater. This study reviewed the latest information on the presence of PMMoV and human enteric viruses in water environments and in wastewater (water) treatment systems to evaluate the suitability of PMMoV as an indicator virus for water safety and quality. PMMoV was present in all types of waters (e.g., wastewater, surface water, groundwater, coastal water and drinking water) in greater prevalence than human enteric viruses. PMMoV was also removed less or similar to human enteric viruses in various wastewater (water) treatment systems (including disinfection treatment). These results suggest that PMMoV can be used as a suitable indicator virus for 1) assessment of water quality polluted by domestic wastewater; 2) assessment of virus removal efficiency in drinking water treatment plants and 3) assessment of viral safety for drinking water.