For most facility managers, reopening from the COVID-19 outbreak will be the most important and stressful achievement in their careers. Yet, a November 2020 survey by Arizona State University and the World Economic Forum found that less than 20 percent of more than 1,000 responding companies were testing workers, citing cost and complexity as the biggest deterrents. “Not testing” is not a viable strategy and has only exacerbated attempts to contain a fugitive and mutating virus. Fortunately, the scientific community and specifically a group that includes public health, building science, epidemiology, industrial hygiene, civil engineering and environmental science specialists have developed environmental monitoring techniques that will reduce FM’s coronavirus monitoring costs.

The beginning

In the fall of 2019, no one was studying COVID-19, because no one knew the disease existed. By the end of March 2020, a pandemic was declared. Communities and schools began testing their wastewater for the presence of COVID-19, many finding positive results, often weeks before symptoms were observed. Unfortunately, wastewater testing data is limited because the lag time from infection to shedding through feces and urine and from recovery to when shedding stops, is unknown. Therefore, wastewater monitoring is primarily used for observing trends in the level of COVID-19 presence.

This left researchers desiring environmental data, not based on shedding in feces and urine. They already knew COVID-19 could be detected in air and on surfaces in COVID-19 wards in hospitals. They also knew the coronavirus survived on surfaces for several days, until October, 2020, when researchers from the Australian Centre for Disease Preparedness announced a laboratory study that showed the coronavirus survives for up to 28 days at room temperature.

This coronavirus surface survivability phenomena fueled a focus on surface testing as a potential early warning and monitoring tool that, when done weekly, can give FMs and public health specialists the ability to detect the coronavirus in facilities a week before any symptoms are observed in occupants.

FMs and health officers use this environmental surface testing data to determine optimum facility layouts to minimize exposure, which areas need to be recleaned and resampled and which occupants should be clinically tested.

The cost of testing

Clinical testing is the single most costly component of a COVID-19 response strategy with tests averaging US$100-$150 for a reverse transcription polymerase chain reaction (RT-PCR) test, considered the gold standard. They have a 24-72 hour turnaround time and are effective in detecting COVID-19 shed from both pre- and asymptomatic carriers.

Antigen tests (formerly called Rapid Tests by the U.S. Centers for Disease Control), identify specific proteins on the surface of the virus. These were the tests the U.S. government made the focus of its strategy before the White House COVID-19 outbreak in September. Unfortunately the U.S. government also allowed its use for large-scale asymptomatic screening without fully exploring the consequences.

In November 2020, after the CDC had already published a notice on false positives and false negatives associated with antigen testing, The New York Times published probably the most concerning study conducted by the University of Arizona. Researchers found the rapid test could detect more than 80 percent of coronavirus infections found by a slower, lab-based PCR test for symptomatic students and staff. But, when the antigen test was used instead to randomly screen students and staff members who did not feel sick (pre- and asymptomatic), it detected only 32 percent of the positive cases identified by the PCR test. “The data for the symptomatic group is decent,” said Jennifer Dien Bard, the director of the clinical microbiology and virology laboratory at Children’s Hospital Los Angeles (California, USA), who was not involved in the study. “But to get less than 50 percent in the asymptomatic group? That’s worse than flipping a coin.”

Does environmental monitoring work?

Percent positivity is exactly what it sounds like: the percentage of all coronavirus tests performed that are actually positive, or: (positive tests)/(total tests) x 100. The percent positivity helps public health officials answer questions such as: what is the current level of COVID-19 transmission in the community and, is enough testing being done for the amount of people who are getting infected?

The University of Southern Florida (USF) is one of the first universities that implemented environmental monitoring as a component of its comprehensive COVID-19 response plan, and it has resulted in a positivity rate of only 0.002 percent as of the end of September, 2020. At USF, when an area shows contaminated surfaces during their weekly monitoring, students are removed and tested as opposed to mass testing.

To put USF’s positivity rate in perspective, the state of Florida had a positivity rate of more than 12.5 percent on Jan. 3, 2020. “Asymptomatic individuals may never even know they are infected,” said Donna Petersen, dean of the USF College of Public Health and chair of the COVID-19 Task Force. “But while they may not experience any symptoms, they can spread the virus and infect more vulnerable populations. Environmental testing is a critical component in early identification of these cases.”

Almost a year since the pandemic was declared, the CDC is focusing on environmental monitoring as a primary method for screening and monitoring indoor spaces for the presence of COVID-19.

The future — mask testing: It can’t come soon enough

Where environmental monitoring will prove most valuable has yet to be demonstrated on a large scale but holds huge promise. Swabbing masks, for example, as a substitute for invasive clinical antigen tests, or what the CDC previously called call rapid tests, which have been plagued with accuracy issues.

If someone were going to design a personal sampling device, it would probably look like a mask. Everybody wears one, they are worn all day and it is in contact with the exact part of the human anatomy where the virus lives and from which it spreads: the nose and mouth. They are also cheap and disposable so it is easy to provide masks and ask someone to return their mask for testing.

A mask’s function is to collect coronavirus so it cannot be spread to others. Why not have the mask do double duty as both a preventer of the spread of coronavirus and collector of coronavirus for testing? It is the last logical component of any environmental investigation, going from wastewater to surfaces to source (individuals) before investment in clinical testing.

Building occupants can be asked to pick up masks when they come in on the last day of the week and drop them off at the end of the day. A few masks can be pooled and tested with one swab at a cost of about US$10 per person instead of US$100 per person. When a positive test result is found, those occupants should be clinically tested (even though it uses the same testing methodology). If samples are pooled, three occupants may need to be clinically tested if a positive mask test result is found. Because schools, universities, assisted living facilities, nursing homes, prisons and workplaces can require mask testing and because it is non-invasive, there should be little resistance.