Rather than screening each individual separately, pooled testing combines samples to minimize the number of tests. Only if one of the combined samples tests positive are further tests necessary to narrow down the pool and see who it was, meaning schools need fewer tests and less wait time to identify which students and staff members need to be isolated or quarantined.
The Massachusetts Department of Elementary and Secondary Education (DESE) recently launched a new pooled-testing program at public and charter schools across the state through testing providers Ginkgo, CIC Health and Project Beacon. State officials encouraged schools looking to re-introduce in-person learning to apply for the program, which provides participating districts with test kits and software to track results.
According to a DESE email to Government Technology, the state will fund the initial launch period through the help of federal coronavirus relief funds. Officials project the program, set to run until April 18, will cost somewhere between $40 million and $60 million. Over 150 districts and schools had signed up as of Thursday, representing a total of 952 schools. The department provided no further comment.
The move comes months after districts like Salem and Wellesley public schools piloted saliva pool-test programs last semester through New York-based diagnostics company Mirimus Clinical Labs. The goal was to provide a cheaper alternative to standard testing methods and enable schools to test larger numbers of samples with more frequency, according to Mirimus CEO Prem Premsrirut.
Despite criticisms about the sensitivity and accuracy of pooled testing, Premsrirut believes this method can help districts with limited funding and resources to track the virus before a major outbreak occurs and results in school closures.
“We just have to be clever about how we test people through this public health crisis. Not everyone needs an individual test, so we need to use the most sensitive and accurate test for a large volume,” Premsrirut said. “I don’t know any school that would be able to test [without this method] on a regular cadence and 100 percent.”
Mirimus currently works with more than 400 schools across the U.S., as well as nursing homes, professional sports teams and Fortune 500 companies, to conduct COVID-19 surveillance testing to quickly isolate cases before they become outbreaks. Premsrirut said the Mirimus SalivaClear platform has been used elsewhere in Massachusetts in Westwood, Needham, Melrose, Lexington and Martha's Vineyard public school districts.
Some schools choose to test all students and staff weekly, while others choose a percentage of students and faculty each week to get tested once a month. Through Mirimus' pooled testing method, which combines 24 samples at a time, schools were able to test at around $13 to $15 per individual, compared to $75 to $150 for other types of individual tests.
“I think it sort of forced [schools] down this road for everyone to consider a more cost-effective method of testing,” Premsrirut said. “We kind of set the bar to push the pricing down really far.”
Salem Public Schools Chief of Opportunity and Response Chelsea Banks said their partnership with Mirimus — among the first pooled-testing programs in the state — initially focused on staff and high school students. Noting the use of this method in a handful of districts like Salem, the state developed its current pool-testing initiative, providing an even cheaper method to conduct pooled testing using nasal swab samples at an average of about $3 to $5 per test.
Salem staff members are still screened using the Mirimus method, but the district now tests the bulk of its students through the state program, using nasal swabs and additional confirmatory testing. Banks said the district, currently comprised of about 2,600 in-person students, has been “very fortunate” over the past three weeks, noting that officials recorded zero positive samples during the last round of tests.
“It did help build confidence that we have had an approach as a district to put in every layer of protection that we have available to us,” she said, later noting that the system has tested “at least 300 people, if not 400, during different weeks.”
Banks said this additional layer of surveillance, along with masking and school sanitation measures, has given educators, students and parents more peace of mind about returning to in-person learning amid a public health crisis in which universal vaccine availability could be months down the road.
“With all of these layers of mitigation, we do feel that our schools are safe to be open, and that is a combination of all of the factors,” she said. “And testing adds a layer to that.”
The current pool program, Banks said, is “pretty straightforward” in terms of protocol. After getting parental consent to opt students into the program, schools can then begin testing large volumes of samples. The state also partnered with the nonprofit Shah Family Foundation, which has helped guide the program through resources such as its COVID-19 Educational Training website. So far, Banks said everything has been running smoothly.
“The testing has been going really well. It’s easy enough to implement for the staff,” she said.
While the staff needed for its Mirimus pilot program was “minimal," Banks noted that it takes an all-hands-on-deck approach to test large student populations across 11 campuses, even with the pooled method.
“We are able to go to classrooms and pull kids into the hallway and test right now, but what we have found is that you need [more staff to help] in order to launch this, because our school nurses have incredibly full plates this year with all the things they’re doing to manage in-building school children during COVID,” she added.
Editor's note: This story has been updated to clarify the methodology behind pooled testing.
