Where are the Rapid Tests? Bates Testing Center Switches to Pooled Testing

Katherine Merisotis/Bates College

Bates has shifted to a pooled testing process for their surveillance testing to prevent COVID spread on campus.

Frequent testing has become one of the major resources allowing Bates to continue in-person classes, and consequently, upperclassmen have become exceedingly familiar with the routine PCR and antigen tests over the past 2020-2021 academic year. However, antigen tests are running out, and not just at Bates. 

“We do have a supply on hand, but it is limited and because the federal government is purchasing so many of these rapid antigen tests, it remains unclear as to when we will receive an additional supply of these rapid antigen tests,” Nick Cooke and Scott Lehmann, the co-directors of the COVID-19 testing center and contact tracing, told The Student.

An article published in the The New York Times on Sept. 21 explained that many other countries, such as Britain, France and Germany have made rapid antigen tests widely available for its citizens. The U.S. has not done the same. 

In order for rapid antigen tests to be approved by the FDA, they have to go through an extensive evaluation of its sensitivity—the same used for high-tech medical devices. The rapid antigen tests must be able to demonstrate a high enough sensitivity that nearly matches those required for PCR tests, which is usually not the case for rapid tests. 

However, since PCR tests often pick up small amounts of COVID-19 that are not contagious to other individuals, rapid antigen tests do not have to be as sensitive. They will still identify about 98% of cases where an individual is contagious for COVID-19. 

The solution that Bates has turned to due to the lack of antigen tests available: pooled testing. 

Shortly after the conclusion of the baseline testing students participated in after arrival, Josh McIntosh, the vice president for campus life, released a statement on Sept. 8 announcing the switch to a pooled testing approach. 

The procedure for pooled testing uses a single PCR test for ten samples. If a pool indicates the presence of COVID-19, all individuals in that pool will be required to test again using antigen testing to determine which individuals are positive for the virus. 

The new approach is still in partnership with the Broad Institute, which is the same COVID-19 automation testing system that was used by Bates during the last academic year. 

This new method is much more efficient than PCR testing for each individual sample. “Ten samples in a tube, all being tested simultaneously, means that you can run one test and get 10 negatives all at once, clearing a group of 10 people with that single test,” Cooke and Lehmann explained. 

Even in the case where there are positive results, the Testing Center still ultimately has to run fewer tests overall.  Next, a reflex test is performed using rapid antigen tests on all individuals in the positive or inconclusive PCR pools to yield the quickest results. 

Not only does pooled testing limit both the number of PCR and antigen tests used, but it also allows the Testing Center to cut their staffing requirement in half. 

“During the last academic year, we had a significant amount of support from people all over the campus who shifted their service to fill other roles, including quite a few who helped at the testing center. As we returned to the full campus experience, they needed to return to their usual roles and we needed to reduce the demands on staffing at the testing center,” Cooke and Lehmann said. 

Bates Health Services (BHS), who also uses rapid antigen tests, sent a letter to students on Sept. 15 describing the procedure students must follow if they are experiencing symptoms of COVID-19. 

The letter directs students who have symptoms to call BHS at 207-786-6199 where they will speak with a medical staff member. If the staff member deems it necessary for the student to be seen at BHS, an appointment will be made. Only during the appointment will the medical provider determine if a rapid antigen test is necessary. 

If a student presents with worsening respiratory symptoms along with fever, BHS is more likely to do an antigen test, Kathy Morin, the BHS Office Manager, explained to The Student.

Brenna Callahan, the Student Health Support and Outreach Specialist, said that although their procedures for students who have symptoms have not changed, BHS felt it was “important to make sure students understand what to do if they’re not feeling well.”

“Because some of the symptoms of COVID-19 do overlap with other illnesses, we understand that some students who are not feeling well might be confused or anxious about how to proceed, including with handling their symptoms,” Callahan stated. 

This is why BHS released the letter shortly after the announcement of the new pooled testing procedure. 

According to Cooke and Lehmann, an almost entirely vaccinated campus community allows for a more efficient model for testing symptomatic and asymptomatic students, not necessarily less testing. Although a highly vaccinated population is at low risk for developing severe symptoms, the transmission risk in Androscoggin County is currently classified as high by the Maine CDC

“We must continue to work to mitigate risk in both the Bates community and in our surrounding community, through masking measures and employing surveillance testing as an important public safety measure,” Cooke and Lehmann asserted.