Dashboards. Recall, wastewater concentrations can be shown alongside clinical testing percent positivity in Oregon on the OHA Wastewater Surveillance Dashboard. If you select SARS-CoV-2, then select a city, a plot viral concentration with time is be shown. Selecting one of the points will indicate the variants found in that sample. Wastewater concentrations and variants in Oregon can be compared to regional and national trends on the NWSS Dashboard. 

Testing the effect of filter pore size. Late in the fall several utilities (Astoria, Boardman, Canby, Grants Pass, Hood River, Lincoln City, Port Orford, Roseburg, Salem) helped test the possibility of using 0.6 um pore size electronegative filters instead of 0.45 um pore size. Thank you for your assistance! While the 0.6 um filters did result in much faster filtering times, the pathogen concentration results had a higher variability than the 0.45 um filters. Therefore, we decided not to change the filtering procedure. We welcome suggestions that may make utility collection efforts easier or more efficient.  

Sampling supply schedule. Since August, we have been following an 8-week supply schedule, where we send utilities 10 weeks of supplies every 8 weeks. We did this to ensure no one ran out of supplies, which had been common prior to August. This change, in conjunction with our reduction from 2 to 1 samples per week in September, has resulted in some utilities having a large inventory of sampling supplies (see photos from Ontario and Dallas!). We will be asking utilities by email in the next 8 weeks if you need supplies or would like to pause this cycle.

OHA Communicable Disease Summary. Last January (2023), OHA published a summary  describing wastewater-based surveillance (WBS) in Oregon, focusing on Bend. From the article “… Given the limitations of case-based surveillance, epidemiologists are increasingly turning to community-level surveillance methods such as WBS. WBS for COVID-19 offers several advantages over traditional surveillance methods. WBS allows the rapid detection of community disease spread, captures mild and sub-clinical infections that would be missed by clinical surveillance efforts and functions independently of healthcare-seeking behavior and testing access.” See the full summary for more information.