Imagine this: In early September, a large college campus welcomes back students. Hoping to return to some sense of normalcy after a tumultuous summer, the school has prepared various measures to protect students from contracting covid-19. Classes will be hosted both online and in-person, masks are mandatory everywhere on campus and randomized testing will be conducted every week. An asymptomatic student—unaware they are carrying the virus—moves into a dorm with 100 other students. They share the same doors, the same common spaces, the same elevators and the same bathrooms. Despite the school’s efforts, within two weeks, an outbreak has occurred on campus, and the school closes almost as quickly as it opened.
This scenario has played out in similar ways across the country since the school year began. Infections have dramatically spiked in college towns since late August, despite seemingly robust protocols and diagnostic testing.
If there’s one thing that’s been learned from the past few months, it’s that while masks, diagnostic testing and physical distancing have helped to slow the spread of covid-19, they’re not enough. To reopen schools and businesses—and more importantly, keep them open—we need another tool in our epidemiological kit: environmental surveillance testing.
What is environmental surveillance testing
Environmental testing refers to collecting and testing samples from surfaces, air and wastewater for the presence of the SARS-CoV-2 virus. Using the same gold-standard qPCR (quantitative polymerase chain reaction) technology as clinical diagnostic testing, the test measures a specific RNA molecule in real-time, multiplying and amplifying it—so that trace amounts of virus can be detected.
Recently, the CDC acknowledged that Covid-19 spreads through aerosols produced when an infected person coughs or sneezes, which can then linger and settle onto surfaces. A study by the World Health Organization (WHO) showed an increase in SARS-CoV-2 RNA can be detected in wastewater samples days before covid-19 is detected through clinical diagnostic testing.
If the virus is found in an environmental sample, it signals a breach of public health within a particular community. That early warning—before symptoms have already started to appear—enables contact tracers to go to work in a more targeted fashion.
Routine environmental surveillance is known to be particularly effective and has been used for decades in food production and healthcare facilities.
“It represents a noninvasive way to get insight into overall population health,” said Pat Whalen, chief executive of LuminUltra, a biological diagnostic testing company based in New Brunswick, Canada, with over 20 years of experience in developing biosafety surveillance solutions for everything from drinking water to food & beverage to wastewater treatment.
A holistic approach to testing—combining environmental surveillance with clinical diagnostics—is a matter of public health. “Some people call it a cluster buster,” said Dr. Jordan Schmidt, director of product applications at LuminUltra. “Instead of the virus moving from one presymptomatic or one asymptomatic person into dozens, maybe it only spreads to one or two people, because you’ve caught it with environmental testing before [it’s been] determined that they’re even sick, or they might never determine that they’re sick because they’re asymptomatic.”
This foresight will play a major role in our economy’s ability to stay open. In order to maintain momentum in our return to normalcy, covid-19 will need to be recognized and mitigated quickly as it appears.
The right information can help stop the spread
This type of testing can cover larger populations than one diagnostic test, and if performed consistently in communal spaces, it’s essentially a method for conducting group testing and tracking the health of, for example, a school, office or even an entire town. The presence of the virus on a surface or in wastewater can act as a canary in a coal mine, so to speak, and can be crucial in flattening the curve.
“Prevention requires proactivity,” Whalen said. “If you’re waiting until people are infected, you’re sacrificing a head start to take action and prevent other people from getting infected.”
According to the CDC, about 40% of covid-19 transmissions occur before the infected person shows any symptoms, if they ever do. Waiting until symptoms appear can sacrifice three to seven days during which action could be taken to prevent other people from getting infected. By then, the infected person may have gone to their office, taken public transit or attended an in-person class, putting entire communities at risk.
Superspreader situations like this could be mitigated with the right technology and protocol. For example, cleaning and disinfecting a classroom each day (rather than only at week’s end), and then validating the effectiveness of that process with environmental testing, can assure that students are returning to a verifiably safe classroom the next morning. Consistent surveillance is key. Once a positive test occurs, the next stop is to begin to locate and isolate the origin and put protocols into place to stop it from spreading—breaking up a cluster before it even forms.
User-friendly testing devices like LuminUltra’s GeneCount can process environmental samples in under two hours and provide easy-to-read results while maintaining the same accuracy as lab-based tests. These on-site monitoring solutions can test and report on multiple samples simultaneously, providing high throughput with no time lost in transit to a lab. Once the virus has been identified, clinical testing, contact tracing and isolation protocols can quickly be put into action.
“It’s additional information about the virus that’s relatively easy to get—one more tool in our surveillance toolbox,” said Angela Rasmussen, an associate research scientist and virologist at Columbia University. “I think it should be rolled out at least in major cities where it would be fairly easy to implement,” she said, noting that wastewater testing, in particular, would indicate the need for more human testing and contact tracing, as well as alerting local health care officials that patients may be at risk.
“Environmental testing on wastewater has been able to predict new outbreaks everywhere from educational institutions to entire cities days in advance,” Whalen said. Globally, environmental monitoring has become commonplace in countries like France, Singapore and Australia, that have successfully tracked and curbed outbreaks with data from wastewater.
Additionally, environmental testing can be used to validate disinfection protocols. A recently published study in the Virology Journal concluded that the virus can remain infectious on a variety of surfaces for four weeks, perhaps longer. Once cleaning solutions have been applied, facilities can use environmental testing to ensure that no virus remains, thus confirming the efficacy of their process. That data can inform what disinfectants are used, the methods being implemented, or how long disinfecting solutions are left on a given surface in order to be effective. “This can provide value in high-risk areas like hospitals and long-term care facilities by identifying when disinfection has actually been achieved,” Whalen said.
Why it matters
68% of Americans are concerned that coronavirus-related restrictions on public activity are being lifted too quickly, while 70% are troubled by the state of the economy. But the choice between reopening and staying closed is a false dichotomy.
When it comes to reopening, it’s possible to help people to feel safe and have businesses remain open, but a holistic approach to monitoring and responding to the coronavirus is crucial. Reactive approaches to safety, like waiting for people to show symptoms before deep cleaning facilities leave too many vulnerable.
The combination of clinical testing and environmental monitoring can drive a powerful shift from being reactive to being proactive and is the most comprehensive way to stay one step ahead of covid-19.
Environmental monitoring helps communities help themselves with a snapshot of public health that is the first step in effective protection. Because as LuminUltra’s Whalen puts it: “What gets measured, gets managed.”
Pew Research Center
Centers for Disease Control and Prevention
World Health Organization
Partnership for New York City
U.S. Department of Labor
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