Wastewater-based epidemiology- A window into the health of our communities
By Purcellville Mayor Kwasi A. Fraser
Two years ago, I invited the leadership of Biobot, a biotechnology start-up, to present their testing and research in the area of opioid consumption in a community. Owing to the disastrous impact of opioids within our society and the ongoing litigations, it was important to have ways to measure and to monitor the before-and-after impacts.
Impressed by the Biobot opioid solution, I saw merit in using it to justify funding for corrective action plans within communities from the future settlements. Essentially, with the Biobot opioid solution, municipalities could produce data to show the efficacy of response strategies to the opioid crisis. Further engagement with Biobot, however, was placed on hold as a result of the COVID-19 pandemic.
In April 2020, I engaged Biobot to discuss its wastewater-based epidemiology surveillance initiative in collaboration with researchers at MIT, Harvard, and Brigham and Women’s Hospital for the detection of SARS-CoV-2, the virus that causes COVID-19. As with their opioid testing and research solution, I was impressed with their solution for SARS-CoV-2 and, in particular, its potential to be used as an early warning indicator of the virus’s spread in our community.
Equipped with such a solution, elected officials and Health Department leaders will be better prepared to make strategic and tactical decisions. In addition, this capability will be of immense value as vaccines for COVID-19 become available, since it will monitor and present the before-and after-states of a community’s health.
Subsequently, upon obtaining commitment from a contractor, Inboden, to collect and ship the 24-hour influent sewer sample from our treatment facility, I convinced the Purcellville Town Council to allow our wastewater treatment facility to participate in the Biobot COVID-19 pilot project.
Inboden was used because of its expert capability and willingness to support our Town with the pilot, and to alleviate the concerns of our Town Manager about staff contracting COVID-19 from exposure to raw sewage. With Inboden engaged with scheduled access to our wastewater treatment plant and in coordination with Biobot, the Town Council unanimously voted to support this pilot.
The May 13, 2020 first round of testing estimated 50 cases in Purcellville. That estimate then spiked to 320 cases one week later, but decreased to 65 by the end of the month.
That spike in cases was similar to a verified spike in new COVID-19 cases in Loudoun County, according to its health department.
Like all municipalities during the COVID-19 pandemic, we face ongoing fiscal constraints, and although we saw the value of the COVID-19 research, other items took priority and required funding, so we decided to suspend the testing. During that time, I applied for a grant from RADx to continue this research pilot, but its reviewers opined that, it did not meet the Project Review Criteria of the RADx solicitation as presented in the application.
Over the past several months, I have continued to follow the progress of wastewater-based epidemiology and also have championed the knowledge transfer and awareness of it among my peers in the National League of Cities, representing 1,900 cities in the United States. Recent analysis and quantification demonstrate the early warning indicator capabilities of this solution.
In fact, there is compelling evidence that the COVID-19 virus sheds in stool in advance of symptoms being materialized. As such, due to the early onset of viral shedding, along with an additional delay between the presence of symptoms and clinical test results, wastewater data has been shown to be a reliable leading indicator of COVID-19 cases.
In short, wastewater provides an early warning for cases that will be diagnosed and reported in a community several days later. This is significant, given the fact that current testing and hospitalization data does not account for asymptomatic cases which are believed to represent a high proportion of any given infected population.
According to Dr. Anthony Fauci, 20 to 40 percent of infected people display no symptoms. This means that the majority of folks who are asymptomatic are not represented in the current testing being done because they don’t know they have the virus and are not likely to get tested. The current testing and hospitalization data provide a narrow and delayed view into the spread of the virus within a community, whereas wastewater surveillance presents a broader view into current and future states of the virus spread within a community.
Based on wastewater analysis reports, the below chart from Biobot, shows the virus concentration in wastewater (blue lines) increased a few days before new cases (red lines) showed a similar increasing trend in each corresponding location.
The current testing and measurement system relied upon by our communities is reactive and based on symptomatic individuals, hospitalization, and sadly, deaths. It fails to account and to prepare for the potential severity of the outbreak. Wastewater-based epidemiology is proactive and complementary to the current testing systems, providing a response system that prepares us for future outbreaks and a solution for the current limitations in our national data infrastructure so we have real-world evidence in real-time.
Armed with this predictive indicator of the number of COVID-19 cases within a community, leaders will be better informed to make important decisions like reopening businesses and schools responsibly and safely.
Now more than ever, I am convinced of the consequential value of this early warning indicator, and I am driven to support efforts to develop a nationwide network of sewer systems and labs, like the one envisioned by the Center of Disease Control, to become the windows into the health of our nation during and after COVID-19.
To make this a reality, I am committed to partnering with each of the 1,900 cities represented in the National Leagues of Cities, certified labs, Health & Human Services, CDC, and other key stakeholders. Below is a depiction of the National Wastewater Surveillance System envisioned by the CDC.