Biobot's COVID-19 community wastewater tiers help guide interpretation of SARS-CoV-2 wastewater data
Wastewater concentrations of SARS-CoV-2 span an extremely wide range, from less than 10,000 virus copies per liter (c/L) of wastewater to over 1,000,000 c/L. Biobot’s community wastewater tiers help guide interpretation of wastewater concentration values from wastewater treatment plants, pump stations, and manholes.
Wastewater tiers provide at-a-glance insights into what is happening with SARS-CoV-2 in a community.
The figure below shows wastewater concentrations over time in one U.S. county, plotted against a log-transformed y-axis.1 Each color band represents a wastewater tier. As the figure shows, the effective concentration values from that county’s wastewater samples were in Tier 2 in July 2021, rose through Tier 3, then peaked in Tier 4 in January 2022. Throughout 2022, effective concentrations stayed primarily in Tier 3, reaching Tier 4 at times. Thus, levels of SARS-CoV-2 in the community were substantial-to-high during most of that year. This visualization, which overlays wastewater data onto community tiers, provides an example of how to communicate what levels of wastewater concentrations mean for a community.
Biobot’s community wastewater tiers contextualize wastewater data, relating effective concentration values to SARS-CoV-2 activity in a community.
This approach helps answer the difficult question of whether the level of SARS-CoV-2 in wastewater is “high” or “low.” For example, wastewater concentrations that are consistently in Tier 4 suggest that there are consistently high levels of SARS-CoV-2 in a community.