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After months of tribulation, Methodist Health System found a solution to our COVID-19 testing challenge in high-throughput (HTP) antigen tests, which could be run on analyzers already installed in our hospital labs.
One year and over 590,000 deaths later, COVID-19 continues to exact a heavy toll on hospital systems across the country. Through it all, the Methodist Health System (MHS), including the hospital where I work in the Dallas-Fort Worth metroplex area, has found innovative ways to keep our patients and employees safe—all while ensuring that critical care services continued undisrupted.
Given the staggering scale of the pandemic, particularly during the grim winter months of early 2021, safeguarding our hospital system from COVID-19 was no easy task. Fortunately, however, by executing a testing strategy that leveraged fast, accurate, and reliable high-volume COVID-19 antigen tests, MHS was able to reduce infections, protect patients, and save lives.
Ultimately, the success we achieved by utilizing these high-volume testing solutions demonstrates how this same strategy could add enormous value to hospital systems nationwide. It is therefore worth elaborating on what we did “right,” the challenges we encountered, and how we evolved over the course of the pandemic to respond to the greatest health crisis of a generation.
An Evolving Testing Strategy
During the initial phases of the pandemic, COVID-19 threw the proverbial “kitchen sink” at us. As cases began to surge across Texas, we knew that ramping up our testing efforts was absolutely critical to isolate infectious patients and protect hospital staff. To that end, we were among the first hospitals in the region to deploy polymerase chain reaction (PCR) tests, which are considered the gold standard of COVID-19 diagnostic assays.
However, as useful and reliable as PCR tests were, we quickly encountered serious operational challenges. Due to limited PCR testing supplies, our hospitals could only test individuals who were either exposed to SARS-CoV-2 or displayed symptoms. This left a huge gap in our screening approach, since asymptomatic individuals could slip through the cracks undetected. To make matters worse, due to the longer turnaround times associated with PCR testing, it was difficult to gather results that were timely and actionable.
Recognizing these challenges, we began searching for alternative testing solutions that could yield results rapidly. Here, rapid point-of-care (POC) tests, as the name suggested, seemed to fit the bill.
Unfortunately, as with PCR assays, our initial optimism surrounding POC tests quickly transformed into measured frustration. Over the subsequent months, we quickly learned that POC tests—while incredibly helpful when utilized among small numbers of patients—were difficult to administer at scale. Especially amid circumstances in which dozens of individuals needed to be tested at a time, POC results were usually delayed, resource-intensive, and not always reliable. If our emergency department experienced a surge, for example, turnaround times for the POC tests were anything but rapid, causing immense frustration among physicians and patients alike.
To get accurate and consistent results at scale in our hospitals, we needed a solution that could run dozens of samples at the same time and return accurate results quickly, when they were most actionable.
Our High-Throughput Antigen Testing Solution
After months of tribulation, we finally found our answer in high-throughput (HTP) antigen tests, which could be run on analyzers already installed in our hospital labs. Since these analyzers were largely automated, this allowed our lab technicians to run hundreds of samples per hour, finally giving us a much-needed capacity boost. Better still, the same analyzers could also process antibody tests, which have been another important pillar of our broader COVID-19 response.
With this new high-throughput diagnostic tool as our first line of defense, we implemented a simple algorithm to reduce viral transmission and protect patients and hospital personnel.
Here’s how it worked:
First, all patients—whether or not they displayed symptoms—were tested with a high-throughput antigen assay. Following this initial screening, if a patient was symptomatic or exposed to someone with COVID-19, a subsequent PCR test was used only to confirm a negative antigen result.
The benefits of our revamped testing strategy soon became apparent. High-volume antigen tests proved to be highly accurate, yielding extremely low false positivity rates. What’s more, these lab-based antigen tests provided quick and consistent turnaround times for results, a critical factor and selling point for our physicians and nurses on the front lines of care.
Our lab technicians also appreciated the streamlined, automated process provided by HTP antigen assays, which allowed them to run hundreds of tests at a time on analyzers they already knew how to operate quickly and efficiently.
The successes of our new testing approach had positive ripple effects across the Dallas-Fort Worth Methodist Healthcare System. For example, since HTP antigen assays only required patients to be swabbed once (as opposed to POC tests which often required a second swab to confirm results through a reflex test), we were able to preserve critical diagnostic resources. This also increased patient comfortability, since tested individuals only needed to be swabbed a single time. Finally, our new approach allowed us to preserve precious PCR resources, including reagents.
Taken together, the use of a high-volume antigen test allowed us to achieve our goal of getting reliable results with consistent turnaround times. Moreover, the deployment of this new diagnostic tool, right before COVID-19 infections surged for a third time following the new year, couldn’t have come at a better time.
As the nation inches closer to herd immunity through a combination of vaccinations and natural infection, our story underscores the ongoing need for widespread COVID-19 testing, especially in America’s hospitals. It is my hope that healthcare systems across the nation can learn from this example and achieve the ultimate goals of safeguarding vulnerable patients, protecting healthcare workers and saving lives.
Karen S. Roush, MD, MBA, is vice chair of pathology at Methodist Health System in Dallas, Texas.