August 31, 2020 (Moscow, Idaho) -- As previously, the City of Moscow Water Reuse and Reclamation Facility has participated in a nation-wide wastewater testing program to monitor the presence of the SARS-CoV-2 (COVID-19) virus in wastewater. Wastewater testing identifies, replicates, and measures viral RNA (ribonucleic acid) within a given wastewater sample.
Since May, the City of Moscow has participated in the Biobot program. Reports for the first three tests conducted in May resulted in no detectable cases COVID-19. Since that time, tests have resulted in the following estimated cases:
- Sample Date - May 27, Report Date - June 26, Biobot Estimated Cases: 190
- Sample Date - July 1, Report Date - July 9, Biobot Estimated Cases: 1,400
- Sample Date - July 13, Report Date - July 17, Biobot Estimated Cases: 1,800
- Sample Date - August 20, Report Date - August 25, Biobot Estimated Cases: 4,000
"Due to the significant uncertainty of case estimation based upon virus loading in wastewater, we are far more interested in the concentration of the virus in the samples and the trends for concentration, than we are in the Biobot estimated case numbers," said Tyler Palmer, Deputy City Supervisor.
In addition to the Biobot testing, the City is cooperating with the University of Idaho as they initiate a wastewater testing program. University staff are reviewing Biobot's findings, and comparing them with their results. Dr. Erik R. Coats and Dr. Thibault Stalder of the Civil-Environmental Engineering and Biology Departments respectively, released a joint statement regarding their concerns with case estimation, and the preferred data presentation for their program:
"Analysis of wastewater to detect the presence of viruses can provide useful information regarding community health. In conducting such investigations, molecular techniques continue to be refined to provide accurate, precise, and reliable data. A key challenge in using such data is how to present results in meaningful terms. Regarding SARS-CoV-2, much remains to be understood about how much virus infected individuals shed at different stages of infection and illness to truly estimate the number of COVID-19 cases from wastewater detection. However, wastewater treatment facilities measure contaminants from city residences. Instead of presenting SARS-CoV-2 data as 'number of people infected,' we are normalizing virus concentrations to the mass of these contaminants. This way, we can monitor trends over time, and such data will provide decision-makers with a better assessment on potential changes in a community's infection rate."
The City of Moscow will continue to conduct testing, primarily with the University of Idaho, but will take periodic Biobot samples for comparison and control.
The Moscow Water Reclamation and Reuse Facility serves the area within Moscow City limits and the Southeast Moscow Sewer District located just outside of Moscow east city limit boundary.
Story Contact: Tyler Palmer, Deputy City Supervisor, Public Works & Services