Through the lens of her computer’s camera, Sara Suliman, PhD, MPH, welcomed a crew of young scientists into the COVID-19 Diagnostics Accelerator laboratory. She paraded viewers past freezers stocked with patient samples and paused at a lab bench, where a technician was preparing to test whether a specimen contained COVID-19 antibodies. He carefully donned layers of personal protective equipment and then extracted 10 microliters of thawed sample to run through a lateral flow assay (LFA), a device similar to a pregnancy test that rapidly determines whether an individual has previously been exposed to COVID-19. “Positive,” Suliman confirmed, as the camera hovered over the three thick bands that appeared on the LFA.
Suliman, of the Division of Rheumatology, Immunology, and Allergy, leads the Diagnostic Accelerator (DA) Laboratory of the Mass General Brigham Center for COVID Innovation (MGBCCI). The lab launched one year ago to evaluate rapid COVID-19 tests that had flooded the market at the pandemic’s onset, some of which received Emergency Use Authorization (EUA) only to later be recalled due to performance issues. Since then, with funding from the Massachusetts Consortium on Pathogen Readiness and Mass Life Sciences Center, the lab has evaluated dozens of tests and is now shifting gears to examine their use in lower-resource settings, where the “gold standard” polymerase chain reaction (PCR) tests are not readily accessible.
At the annual Cambridge Science Festival, a springtime showcase of local, cutting-edge scientific explorations, Suliman and MGBCCI co-director David Walt, PhD, of the Department of Pathology, led a virtual tour of the DA lab, celebrating its first year of work and answering questions about the lab’s next steps.
Accurate, Fast, Reliable and Scalable
“Before we can put our stamp of approval on diagnostic technologies, we need to be sure they are accurate,” Suliman explained to the participants of her virtual tour. “Are we actually identifying all the people who have the infection or are there false negatives? Are we over-diagnosing? These were questions we had to answer early on in the pandemic.”
The need for fast, reliable, and scalable diagnostic tests that can be used in a range of settings has driven the work of the DA lab over the past year. It has now assessed 20 LFAs designed to detect the presence of COVID-19 antibodies and released a web application that allows users to interpret the accuracy of their test results. The group has also evaluated two PCR tests awaiting EUA approval that detect infections by screening for viral RNA and three antigen tests that detect viral proteins. Two other antigen tests are currently under examination. One test the lab evaluated, the BD Veritor System, recently received U.S. Food and Drug Administration authorization.
As the Brigham and other hospital systems have become accustomed to using specific diagnostic technologies, the DA lab has transitioned from evaluating tests in its laboratory to studying their use in different settings, including state-funded community testing sites.
Equitable Rapid Testing
Seeking to examine the use of new COVID-19 rapid tests in low- and middle-income countries, the MGBCCI’s Implementation working group called upon Shahin Lockman, MD, MSc, of the Division of Infectious Disease, and Louise Ivers, MB, BCh, MD, MPH, DTM&H, executive director of the Massachusetts General Hospital Center for Global Health and associate physician in the Brigham’s Division of Global Health Equity. Both researchers have worked internationally for decades; with Suliman, they helped convene a large group of international investigators. This group began a collaborative multi-country study of the BD Veritor and other rapid tests in Kenya, Malawi and Bangladesh. Many of these countries rely on the costly endeavor of processing PCR nasopharyngeal swabs at central labs. Staffing needs, supply chain challenges and difficulties communicating results to patients limit testing capacities.
“Rapid antigen testing is appealing in the United States, but exponentially more so in many other settings,” Lockman said. She recalls a supply chain issue that left her group in Botswana without the capability to do PCR tests for many weeks, a loss that led the country to turn to convenient rapid testing in the interim. The lack of rapid testing has also created economic reverberations, such as limiting commerce when transport workers find themselves unable to cross borders because they cannot access COVID-19 tests.
The collaborating investigators are preparing to publish their findings from their international implementation of rapid testing and are preparing to conduct more work as well. With low vaccination rates in many of these countries, concerns exist surrounding the emergence of new viral variants, which could impact the performance of COVID-19 tests. This multi-country group of investigators (and additional colleagues from Botswana) are planning to evaluate the tests for selection of specific or new variants in these settings.
“There is tremendous research expertise in low- and middle- income countries, and what we can learn from other countries is as important as what they can learn from us,” Lockman said. “Efforts to understand how these tests perform in different environments are applicable in the U.S., and similarly, understanding the impact of emerging variants globally is critical. Vaccine equity is important, and testing equity will be equally crucial.”
Working Locally to Stop the Spread
Meanwhile, the DA lab has also collaborated with Ivers’ local research at the free “Stop the Spread” testing site at Holyoke Community College in Holyoke, Massachusetts. Public health officials in Holyoke, an under-resourced community with a primarily Latinx population, encountered difficulties in reporting PCR results and wanted a cost-efficient way to provide rapid testing. The DA lab was able to pilot use of Access Bio’s CareStart LFA at the testing site and compare results to the PCR test. A paper on the study is forthcoming.
“There are racial and ethnic disparities in how the infection load is distributed in Massachusetts, with Black and Brown communities having higher rates of prevalence than their white counterparts,” Suliman said. “A year since we began our work at the Diagnostics Accelerator, we’ve learned the value of decentralized testing, which is made possible by the availability of rapid tests. But we need to have standard protocols for the tests’ evaluation before they can be deployed.”
The work of the DA lab has been supported by four lab technicians who also recognize the broad applicability of their work. As Sujata Chalise, BS, originally from Nepal, commented during the Cambridge Science Festival tour, “Nepal has been greatly affected by COVID-19, not just in terms of death and positive cases but by economic crisis, unemployment and hunger. The fact that I’m a part of this project, which is trying to contain the ongoing crisis, gives me immense satisfaction and hope.”
Suliman notes that just one year after its launch, “the accelerator has done what it was supposed to do” in terms of evaluating diagnostics in a hospital setting. But, she emphasizes, “The need for testing is not going away. We’re getting documentation of breakthrough infections, that is, infections in individuals who have been vaccinated, and not everyone will receive the vaccine in a timely manner, particularly in low- and middle-income countries. There is still a huge demand in resource-constrained settings for rapid tests, and the need to ensure that our tests are valid and accessible will continue.”