by Sheryl Hamlin
Detecting virus breakouts currently depends on individual testing, preferencing those with symptoms or those who have been exposed to people with symptoms. Because of resource constraints, the asymptomatic population has been less targeted for testing.
According to this article in the VCSTAR. “County health officials have said they wanted to increase testing from an average of 1,500 per week to 4,000 tests. Previously, access to testing has been limited. Patients generally had to show symptoms and be referred by a physician”.
The population of Ventura County is about 850,000. At a rate of 4,000 per week, this would mean the entire county might be tested once in 212 weeks or about 4 years.
Because the new corona virus has been found in untreated wastewater where it can live for an indeterminate period of time, there has been a realization in the scientific community that the knowledge of the composition of wastewater upstream, within and downstream of the treatment plant can become a monitoring tool with faster results than mass PCR testing.
According to scientists in this field, the daily reporting from hospitals and testing services is a lagging indicator but the implementation of real-time monitoring can reduce the lag time to pinpoint outbreaks.
Source:InSitu
Webinar: “Early Detection of Covid-19”
Scientists from InSitu, Inc, GT Molecular,Inc and EcoLucid, Inc presented an informative webinar on the process of wastewater testing, as well as strategies for deploying the technology. Read the notice of the webinar here.
Strategies
Samplers can be placed in sewer connections at hospitals, prisons, schools, inside the wastewater plant or downstream of the wastewater plant. The picture below shows a sampler being inserted into the sewer line.
Source: Chemscan
Samples are placed in vials provided by GT Molecular and sent for testing. Turnaround is measured in hours. Results are placed in a secure cloud-based data area accessed only by the owner of the vials.
Source: GT Molecular
Water Disaggregation
The scientific magic which makes this possible is “water disaggregation”, a technique for statistically determining from a single flow the source of the virus under testing. Read about water disaggregation here. What this means is that based on operating conditions such as time of day, weather and type of institution, the model can disaggregate toilet data from other data in the sewage.
Source: EcoLucid
Viral Sampling
GT Molecular explained that viral sampling is best performed with digital PCR as the GT Molecular slide below shows:
The testing also involves a “spike” virus such as a bovine corona virus which acts to segregate and differentiate the results.
It is important to understand that this type of monitoring will provide a community with near real-time knowledge of viral hot spots. There are more advanced models which can be used in conjunction with this testing to estimate the number of cases.
To view the entire webinar, click here
To read about the author, click sherylhamlin dot com
Get Citizensjournal.us Headlines free SUBSCRIPTION. Keep us publishing – DONATE
New covid strain discovered via wastewater surveillance … https://www.gazettextra.com/news/nation_world/does-covid-prefer-the-gut-now-surging-virus-detections-in-wastewater-prompt-scientific-debate/article_1279119c-fba9-513d-88a6-751d9b047198.html?utm_medium=social&utm_source=email&utm_campaign=user-share
Process in use in Ottowa….detecting COVID from wastewater samples.
https://www.ctvnews.ca/health/coronavirus/new-algorithm-could-help-identify-covid-19-outbreaks-in-neighbourhoods-using-wastewater-data-1.5457797
“Like a lot of the rural West, Yosemite National Park seemed to be a safer haven from the coronavirus. No park employees or residents tested positive. No visitors reported being sick. The fresh air and open space seemed immune. That’s until local health officials started looking for the coronavirus in the park’s raw sewage — that’s right, the poop. ” https://www.sfchronicle.com/health/article/There-were-no-reports-of-coronavirus-in-Yosemite-15414351.php?utm_source=newsletter&utm_medium=email&utm_content=briefing&utm_campaign=sfc_baybriefing_am
Read about a new federal system National Wastewater Surveillance System…
https://www.citizensjournal.us/cdc-national-wastewater-sewage-surveillance-nwss/
Prediction of infectious disease via study of wastewater….. world wide interest…
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7123508/
What is the load in wastewater systems where hospitals are hooked in compared to wastewater treatment plants where there is no hospital input?
It would be interesting to determine if these samples can show the rates of viral inactivation at various points between, say the release from a hospital and environmental areas following treatment plant release and the downstream the environment at large. Are the treatment plants 100% effective or only partially effective? At what point within this process is the virus totally inactivated? Where are the areas where the virus remains functional and what is the human contact within such areas?
Dr Edo McGowan