Mass Antigen Testing: Alternatives to Efficient Diagnostic Testing During a Global Pandemic

Antigen testing provides an efficient, cost-effective way to mass test for COVID-19 which is essential for hospitals. Learn how one reference laboratory is using this test in their daily operation.

As the U.S. ushered in the new year, over 2 million daily COVID-19 tests were performed across the country in January, according to the COVID Tracking Project. While the number seems staggering, some public health experts estimate safely reopening schools and businesses could require performing over 6 million tests in the U.S. every day.ⁱⁱ

While the nationwide demand for testing is on its way up, so too is the shortage of supplies needed to perform COVID-19 tests themselves. This is especially true for the current gold standard for testing, the polymerase chain reaction (PCR) test which relies on a technique to amplify the virus’ genetic material.

PCR tests are almost 100% accurate and return very few false positives,ⁱⁱⁱ however, they are expensive, require specialized set-ups and chemical reagents that are in short supply and typically take 1-2 days to return results.

Additionally, while people wait for their results, those who are infected but don’t yet know it, may continue to interact with others and spread the virus. As hospitals and laboratories all over the country assess their current protocols and ramp up for the tests to follow in the year to come, it’s clear that they will need to implement alternative diagnostic methods that are reliable, affordable and efficient.

Enter The COVID-19 Antigen Test

Antigen testing is a type of diagnostic test that relies on identifying protein segments (antigens) of the virus. There are several types of antigen tests: Point-of-care (POC), mass antigen tests and now a third category – at-home antigen tests like Ellume. Most POC antigen tests can be performed in the doctor’s office using a nasal or nasal pharyngeal swab and have the potential to deliver fast results.

Antigen testing can be a superior first line of defense when PCR testing is impacted because of greater availability and lower pricing. However, while POC antigen tests have a purpose in diagnosing COVID-19, they are difficult and resource-intensive in scale to address high-volume testing needs.

Jelica Wold, senior manager of immunoassay global product marketing at Beckman Coulter indicated there are other limitations to POC tests as well. "POC tests are a one-off test, and throughput for them is typically low – we have heard that between 5-20 POC tests can be performed by one individual per hour," Wold explained. “Compare that to up to 200 tests per hour on a DxI 800."

Also, the same test used to deliver a result within 15-30 minutes to a single individual can’t perform as efficiently when it’s asked to deliver results for 100 or 1,000 individuals. The solution to this problem is scaling up volume using mass antigen testing.

Automated Solutions Enhance Workflow

To address the demand that laboratories all over the country are facing, mass antigen tests work around the challenges associated with scaling high-volume antigen testing. The testing utilizes a higher level of automation, resulting in reduced risk of analytical errors and improved workflow.

Wold explained that having high-volume testing available in the laboratory -- where experience managing the workflow for infectious samples exists -- facilitates the understanding of prevalence and infectious status and allows for containment and management.

Results of mass antigen tests are automatically sent to the laboratory information system, unlike POC tests that are often manually recorded into the EMR. Automated antigen tests have the potential to deliver 50-200 tests per hour depending on the type of analyzer used by the laboratory.

Mass antigen tests can be performed on the same patient population as PCR tests: individuals who are suspected of COVID-19 by their healthcare provider for various reasons, including known infection exposures or working in high-risk environments, as well as asymptomatic patients.

One Laboratory Shifts the Paradigm

Solis Medical Laboratory, LLC, a clinical reference lab that services long-term care facilities in Houston, Texas has outsourced their PCR testing and turned to Beckman Coulter’s mass antigen test in-house for faster results. "From day one of the pandemic, we’ve been focused on turnaround time,” said Dr. Richard Drummond, technical director of Solis Medical Laboratory, “the geriatric population is high risk, and physicians are dependent on lab services to get accurate and definitive clinical data so they can make diagnoses and treat patients."

By using mass antigen testing, Dr. Drummond can quickly identify positive patients and isolate positive employees --which is critical in a delicate nursing home environment. "I was pretty aggressive to get the mass antigen test up and running in-house because it has a 93.3% sensitivity and 100% specificity," he added. "It’s also half of the price of PCR tests, so with the combined savings, the fast turnaround time, and the increased sensitivity, I felt it was a good option for our lab."

Another obstacle many labs are facing are increased costs and a reduction in reimbursement. For that reason, the mass antigen test may be a cost-effective solution.

"Routine lab reimbursement rates have dropped so dramatically over the last 3-4 years, unless you’re a big lab, you’re not going to make it," Dr. Drummond said. "Our expenses don’t seem to be going down, but our reimbursements are really falling so having a decent margin on a test is really helpful to small clinical labs."

The antigen test is a potential business opportunity for impacted laboratories that are experiencing a decline in routine laboratory testing, but an influx COVID-19 tests – the tests which they are now relying on for the bulk of their business.

It’s for that reason that Dr. Drummond chose not to bring POC antigen tests into his lab. He also saw that for POC tests, the sensitivities were too low. "If you have 84% sensitivity, that means 16 of those positive patients are going to test negative," he explained. "In a nursing home, where the stability of patients is critical, you can’t run the risk of spreading infection because you falsely report patients as negative."

According to Wold, Beckman Coulter’s new mass antigen test can deliver high quality, real time results, with up to 200 samples processed per hour on a DxI 800 analyzer. * "The great thing about our high-throughput assay is that already thousands of labs have access to our instruments in the U.S. alone, and so the infrastructure is already there," Wold indicated.

It’s possible to use mass antigen testing in both large and small settings because the benchtop analyzers can fulfill the demands of a smaller institution, while higher-volume instruments with the potential of automation can satisfy the demands for larger workflows. "Another nice feature about our assay is that it can be run in random-access mode, which means you can put it on the line alongside all of your other immunoassays that you already maybe running," Wold explained. "So even someone running those antigen assays at a lower volume could be very well satisfied."

While there is a validation process to get the test running and some manual labor involved in extracting the sample and preparing it, Wold said her team is looking at ways these steps can be automated as well so that the assay can be run in an even more efficient fast, low-touch fashion. "Still, in comparison to some of the 2-step PCR tests that require about an hour or so of hands- on time, or in comparison to the lateral flow antigen tests available that are POC and one-off tests, our assay has some really nice features that can assist in automating the workflow and getting to higher throughput for testing to determine whether a patient is infected with the SARS-CoV-2 virus," she said.

Beckman Coulter has capacity to produce at least 25 million of its COVID-19 antigen tests each month, helping to fill the critical COVID-19 testing gap. The new, rapid and affordable mass antigen test creates the potential for frequent testing so that labs all over the country like, Solis Medical, can provide patients and employees with timely results. When implemented within communities, mass antigen testing will aid schools, institutions, hospitals and businesses all over the country to think about plans to safely reopen. schools, institutions, hospitals and businesses all over the country to think about plans to safely reopen.

Discover more about the new COVID-19 antigen test.