Fecal Source Tracking in A Wastewater Treatment and Reclamation System Using Multiple Waterborne Gastroenteritis...

Area of Science:

• Environmental microbiology
• Public health virology
• Wastewater engineering

Background:

• Gastroenteritis viruses in wastewater pose public health risks.
• Wastewater reclamation systems require rigorous viral monitoring.
• Understanding viral contamination sources is crucial for effective treatment.

Purpose of the Study:

• To detect and genotype gastroenteritis viruses in a wastewater treatment and reclamation system.
• To identify sources of viral contamination in raw sewage, treated wastewater, and lake water.
• To assess the effectiveness of disinfection processes in eliminating viruses.

Main Methods:

• Reverse transcription plus nested or semi-nested PCR for virus detection.
• DNA sequencing and phylogenetic analysis for norovirus and rotavirus genotyping.
• Sampling at multiple stages: raw sewage, A2O process, lake water, and disinfected MBR effluent.

Main Results:

• High prevalence of gastroenteritis viruses in raw sewage (91.7%), A2O-treated wastewater (70.8%), and lake water (62.5%).
• Norovirus GI/14 and GII/13 strains were frequently detected.
• Complete virus removal was achieved after membrane bioreactor (MBR) effluent free chlorine disinfection.

Conclusions:

• The wastewater reclamation system effectively reduces viral load but does not eliminate all viruses.
• The artificial lake may be contaminated by sources beyond the reclamation system, such as aerosols.
• Potential norovirus infection risks exist through reclaimed water use and wind-transported aerosols.