Moscow: Wastewater study shows increased presence of COVID-19

A wastewater epidemiology company estimated there are 1,400 cases of COVID-19 in Moscow by collecting samples on July 1 from the city’s Water Reclamation and Reuse Facility.

The estimate is a stark contrast to the 190 cases the company estimated from tests in late May.

There are 31 confirmed and six probable cases as of Monday in Latah County, according to Public Health – Idaho North Central District.

Moscow applied for and was accepted to participate in a subsidized program to test for the presence of the coronavirus in wastewater, according to a city news release.

Biobot Analytics, a company that studied opioids in wastewater, initiated a program to track COVID-19 in wastewater. Biobot developed a process to identify, replicate and measure the concentration of the viral ribonucleic acid in a given wastewater sample.

Biobot states its methods for detecting COVID-19 in sewage are adapted from Centers for Disease Control and Prevention protocols and rely on detecting genetic fragments of the virus that are excreted in stool. The tests do not determine if the virus is dead or active.

The city provided weekly test samples in May. The first three tests did not detect the coronavirus.

On June 16, the city received the May 27 results, which showed a concentration that Biobot used to estimate 190 cases of COVID-19 in the community. There were five confirmed cases May 27 in Latah County, according to PH-INCD.

On Thursday, the city received results for the July 1 sample, which Biobot used to estimate 1,400 cases in Moscow. PH-INCD reported 20 confirmed cases July 1 in Latah County.

Estimating cases based on concentration is an emerging science and there are several variables, including rain events, daily flow variations and sewer line cleaning, that could affect accuracy, especially in a smaller system like Moscow’s, the release said.

“It is important to note that the Biobot data provides estimates, not actual cases,” City Supervisor Gary Riedner said in the release. “While we can’t rely on the accuracy of the case estimation, the thing that is certain is that we are seeing significantly increased concentrations of COVID-19 in our wastewater. We will continue to monitor levels in our wastewater and continue to share the results with the healthcare professionals.”

Tyler Palmer, deputy city supervisor of public works and services, said the first four Biobot tests were $120 each and subsidized by grant money Biobot obtained from the federal government. The two tests since then were $1,200 each.

Palmer said the city will start submitting weekly samples -- at no cost to the city -- to the UI for analysis. He said the city could cover part of the costs in the future.

The release said the UI Biological Sciences and Civil & Environmental Engineering departments, utilizing funding from the Institute for Modeling Collaboration and Interaction, are initiating a regional wastewater testing program with plans to start processing samples within two weeks.

Riedner said he hopes working with UI will allow for test results to be dispersed more quickly.

Riedner said the city shares the test results with PH-INCD, Gritman Medical Center and city government officials.

“We just want to make sure that everybody has all the information,” he said.

He said the city is not using the test results to institute further coronavirus-related orders.

Residents must wear face coverings in public per a Moscow City Council resolution that expires Aug. 4.

“We’ve done everything that we think is necessary at this point,” Riedner said.

He said in the release the results underscore the need for increased efforts in hygiene, like washing hands, avoiding touching eyes, nose and mouth, practicing 6-foot social distancing and wearing face coverings to help prevent the spread of the virus.

The Moscow Water Reclamation and Reuse Facility serves the area within the Moscow city limits and the Southeast Moscow Sewer District located east of the city limits.

During the COVID-19 pandemic, Biobot has analyzed COVID-19 prevalence in roughly 400 cities across America.

Garrett Cabeza can be reached at (208) 883-4631, or by email to gcabeza@dnews.com.