On Tuesday nights at St. Paul’s School, two safety officers patrolling the grounds split up to collect gallon-sized Ziploc bags from the 18 residential houses.
Inside the bags – labeled with house names – is a series of smaller sealed bags containing bar-coded saliva samples from each resident. The bags are delivered to the health center within the hour and processed on Wednesday mornings. It takes two health center staff members up to three hours to scan the barcodes, create a spreadsheet that matches the vials of saliva with individual students, and package everything up for FedExing to a lab in Brooklyn, N.Y. If any of the tests are positive for COVID-19, Medical Director Dr. John Bassi would receive a call as early as 2 a.m. on Friday.
Pooled saliva analysis is one part of the multi-layered approach to testing employed at St. Paul’s this fall, as the School works to prevent – or mitigate – the spread of COVID-19. Dr. Bassi is leading the charge in a program that also includes random nasal swab (anterior, not the brain ticklers) testing of approximately one-third (or between 100 and 130) of the adults on campus each week and rapid antigen tests to rule out the novel coronavirus as a cause for symptomatic individuals. The nasal swab kits are processed by the Broad Institute of MIT and Harvard, with results returned in 24 hours. Rapid tests are done using a Sofia 2 analyzer that produces positive or negative results for antigens within 15 minutes.
There’s also twice-weekly wastewater testing that can identify the viral shedding from a single COVID-positive individual in a tank that holds 40,000 gallons. That tank, which collects wastewater from 95 percent of SPS buildings, provides a good overview of the campus, with results reported by environmental services company GZA within three to five days.
“People don’t see behind the scenes,” says Dr. Bassi. “It’s incredible the amount of time and energy, staffing, and organizational skills that go into it. COVID [testing] has taken over the health center – we are a testing machine.”
So far, Dr. Bassi has not been the recipient of the 2 a.m. call from the lab at Mirimus, which analyzes the pooled saliva. There have been no positive COVID tests among students this fall, a testament to the hard work being done to isolate the virus before it spreads. Since the end of May, Dr. Bassi and Rector Kathy Giles have been meeting regularly with Dr. James Noble, an infectious disease specialist at Concord Hospital, devising best practices for testing for the students’ return to campus in September and beyond. Working together with Dr. Noble and a team on the SPS grounds, Dr. Bassi chose a protocol that required all students to produce a negative COVID test before returning to campus. They were tested again on arrival and asked to quarantine in their rooms for 24 hours until the test results were known. A third test was administered to all students five to seven days later.
“It was a great way to get them on campus and then put them in an insular state,” says Dr. Bassi. “That proved to be a good strategy.”
One of the reasons St. Paul’s has been successful so far in preventing a COVID-19 outbreak is that Dr. Bassi and other School officials have adapted to rapidly changing guidelines and testing protocols as the pandemic has evolved. Although the State of New Hampshire mandated surveillance testing, the recommendations remained vague. Dr. Bassi decided to add the random testing of adults on campus, including the most forward-facing staff in the health center and food services. As some restrictions have loosened (including the requirement that students wear masks in their residential houses), surveillance testing has been increased. This includes a daily battery of SurveyMonkey screening questions, accessed by a QR code, that asks community members to report any symptoms associated with COVID-19.
Bassi describes the multi-layered approach to testing as the “Swiss cheese model. There is no one perfect solution to avoid this virus.” The multiple methods of testing, he explains, layer the holes in the “cheese” and make prevention more feasible. In addition, the SPS community has adhered to strict social distancing policies, mask mandates, limits on who can visit the campus, and restrictions on students leaving the grounds. The approach has minimized both the exposure and risk of coronavirus spread.
“I salute John; he has done a fantastic job,” says Dr. Noble, the infectious disease specialist, “first to organize this effort and, second, from the first time we talked about this, a lot about our understanding of testing has changed. Yet, all changes have been incorporated into the St. Paul’s system.”
Testing protocols will continue to evolve as the academic year progresses. And with students departing for Thanksgiving and winter break with distance learning in between and through the end of January, the Opening Days testing procedures will be repeated when they return. Both Dr. Bassi and Dr. Noble attribute the effective program thus far to the cooperation of both students and adults at SPS, who have adhered to restrictions and responded to requests to keep the community safe. Faculty advisers, with a Dr. Bassi webinar to train them, have stepped up to collect the pooled saliva samples in the houses. Director of Environmental Health and School Safety Tim McGinley reports that his staff of eight officers has embraced the Tuesday night collection duties. “It’s our small way of lending a hand,” he says. St. Paul’s also benefits from its fully residential student body, which limits the daily reintroductions of people to campus.
“It’s a tremendous advantage that St. Paul’s is a closed system,” says Dr. Noble. “People speak about testing programs for nations like France, Great Britain, Italy, as if you could execute what St. Paul’s has done. Obviously, you can’t, though it may be scalable to some degree. St. Paul’s is a model for how this could be done. I think they have done a perfect job.”
The precautions necessitated by the pandemic may also be responsible for the reduction of typical illnesses seen in residential, educational environments – the common cold, strep throat, and the other viruses that sneak into close-knit populations. It has also brought to task an American culture that frowns upon calling in sick and has asked young people to make sacrifices.
“Let’s face it, this is a challenging year,” says Dr. Bassi. “It’s a challenge for our young people, who thrive on social interactions – but the students here have been good. They follow our instructions. They wear their masks. But they need social interaction. By expanding our surveillance testing, we have been able to relax some restrictions.”