Over the last several months, the rise and spread of COVID-19 has simultaneously overrun health care systems, taken lives, and shut down the world’s most robust national economies. In the United States, many have come to realize that COVID-19 is not going to disappear anytime soon. As states begin to lift stay-at-home restrictions we’re still confronted with a daunting challenge: we still don’t know how far the virus has spread. The United States has tested just over twenty million people for COVID-19, or a little over six percent of the population. And, while epidemiologists don’t fully agree on how many tests per day are needed to adequately contact trace and begin to return to normal society, there is consensus that current levels of testing are insufficient. But there is one atypical place that presents a unique opportunity to help fill the hole that current testing has failed to address: sewage.
Those of us in the wastewater industry have known for years that you can understand a lot about a population by analyzing what comes through the municipal sewage plant. Wastewater analysis, a perhaps surprising epidemiological tool, has been used to detect influenza outbreaks and even the prevalence and types of narcotics use in a city. The field of wastewater-based epidemiology (WBE) has been at the forefront of epidemiological research for years, with experiments and technologies being developed in labs across the nation such as at Arizona State and Yale Universities.
Indeed, recent research has shown that what we flush down the toilet can be a vital tool in helping to analyze the relative prevalence of SARS-COV-2, the virus that causes COVID-19 in a population. By measuring ribonucleic acid (RNA) stemming from coronavirus infections in wastewater, epidemiologists can glean broad population-level conclusions about the outbreak in ways the six percent of testing never could provide. And just like that, this previously niche epidemiological tool with little mass value, has quickly become an invaluable resource in fighting the outbreak.
The process is relatively simple; sludge pellets formed from concentrated wastewater can be scanned for SARS-COV-2 RNA, which is itself amplified using reverse transcriptase polymerase chain reactions (PCR). In addition to simply confirming the presence of the virus within a given location, which itself won’t come as much of a surprise, this testing can also reveal relative volumes of the virus and thus, over time, can be correlated with active infections in the greater population. Most significantly, whereas coronavirus carriers may not become symptomatic for up to two weeks after contraction of the virus, these individuals will quickly begin excreting SARS-COV-2 RNA. In fact, we’re seeing that wastewater may even serve as a leading indicator of future symptomatic outbreaks and hospitalizations, giving us as much as a one week head start.
Data collected from wastewater, in combination with more traditional metrics, can help public health officials create a more comprehensive picture of population health well in advance of a major outbreak. As wastewater utilities and cities begin to realize the incredible power stemming from ongoing data collection and real-time water quality analysis, utilizing RNA to track population health over time represents an opportunity for the wastewater industry to provide yet another value-add to the population it serves. WBE for COVID-19 is a practice that has the potential to save countless lives by allowing public health officials plan for, respond to, and recover from pandemics and do so in a way that can save communities both time and money.
At Sylmar Group, we’re helping some of the leading firms and utilities put advanced WBE tools to work to protect public health. In the water and wastewater industry, we take pride in protecting human health and the natural environment and surprisingly, the 2020 COVID-19 Pandemic has given us another reason to value the stuff that flows through our pipes and, just as importantly, the people, organizations, and technologies that look after it.