Charleston Reporter

Carolinas Hospital System issued the following announcement on February 1.

Heather Hill, supervisor for MUSC's COVID pre-analytical process, checks swabs that have come in for testing to make sure their labels match the names on the list that came with them. Photos by Sarah Pack

While most people are sleeping, members of the COVID-19 lab testing team at the Medical University of South Carolina are wide awake during the Omicron surge. “We’re here 24/7. A lot of our peak time is overnight,” said lab leader Julie Hirschhorn, Ph.D.

“It's all about trying to get the results out as quickly as possible. The sooner that people know whether or not they're positive, the sooner they can take measures to try and keep those people around them safe.”

 Hill prepares to pour samples taken from people worried they have COVID into tubes for testing. She chooses the type of tube based on which of MUSC's testing machines is in use.

She and members of her team offered a behind-the-scenes look at what happens once a swab comes in for testing, the role multiple machines play and what can speed or delay results.

The process begins

When a swab ready to be tested for COVID-19 arrives at MUSC, Heather Hill is often among the first people to handle it. “I work in a methodical way,” said Hill, the supervisor for the COVID pre-analytical process.

 The testing team has streamlined its process during the pandemic. It's now able to get results to patients through electronic health records as soon as a machine finishes testing them.

“What we’re doing here is called manifesting,” she said, as she checked labels on bags containing nasopharyngeal or mid-turbinate swabs. “We’re bringing in the samples. All the samples that come in from other locations, they put information on the manifest list that we then check to make sure that what comes in is actually what’s in the bag.”

A lot of the swabs come in coolers from testing sites around the state, dropped off by couriers throughout the day. Others, from patients in the hospital at MUSC Health, arrive with the help of an internal tube system.

 The lab team, including assistant Ajah White, switches roles frequently to ensure everyone can handle everything.

Hirschhorn said urgent cases go to the rapid testing area, where results can arrive in less than an hour. “Those are scenarios within the hospital when you need a faster turnaround time because of a need to protect our teams as well as the patients. They usually come from inpatients or the Emergency Department. Ideally, we would like to be able to offer a rapid option to everyone, but due to demand and supply across the nation, it has been difficult to get some of these more rapid tests.”

The machines

The rest of the swabs will be tested on slower high-throughput machines capable of churning out 1,600 to 1,800 results a day. “I think our turnaround time, once the specimen arrives in the laboratory, is less than 10 hours right now,” Hirschhorn said, referring to how long it takes to get results to the people waiting for them. 

“If specimen travel is needed by a courier to get the samples from the collection site to the main laboratory, it can add upward of eight hours to the resulting time, due to the time spent in transit. When the laboratory has a lot of specimens to handle, that can also increase the turnaround to 24 to 48 hours because it takes more people and time to process all of those specimens.”

 Lab associate Katlin Thompson, left, and technician Glenda Rebl prepare samples for testing in the Abbott Alinity machine, one of several options at MUSC that can handle COVID tests.

Once Hill or a colleague finishes checking in samples, they’re carefully transferred to tubes and prepared for the next steps. Then, the laboratory has multiple machines at its disposal for testing, including the Panther System, the Abbott m2000 and the Abbott Alinity.

“We do utilize all of those machines, especially in a surge like we've seen recently,” Hirschhorn said. If there’s a problem with one type of machine, such as reduction in the supply of tests, they can pivot to another. “We can shift pretty quickly. Once a specimen is received in the lab and prepared for testing, we try to run it as soon as possible.”

 Liquid from a nasal swab is poured into a tube for testing.

But technicians are careful to confirm the names and dates of birth before a specimen goes into a testing machine. They’re well aware of both public concern about the speed of results – and the need to be precise. Technician Betsy McLaughlin said she and her colleagues do everything they can to get those results out as quickly as possible. “I think people don’t know the whole ins and outs of testing and this particular type of testing. PCR takes a while. This is the gold standard.” 

 A sample is processed through the GeneXpert Infinity machine to do a rapid test for COVID.

PCR stands for polymerase chain reaction testing. According to the National Human Genome Research Institute: “COVID-19 PCR tests use primers that match a segment of the virus’s genetic material. This allows many copies of that material to be made, which can be used to detect whether or not the virus is present.”

That’s compared with antigen tests, which look for viral proteins and don’t have to be done in a lab.

Once a sample is in one of Hirschhorn’s team’s machines, which are subjected to daily quality control tests, it moves through several steps. “In the first step, it’s going to break up the SARS-CoV-2 virions where the virus is located. Then it’s going to isolate that virus. Once the virus is isolated, it’s going to go through a process called nucleic acid amplification. And basically, what that means is that it’s going to look for COVID-19 in particular. If COVID is there, it’s going to amplify it. And if it amplifies it, it’s going to detect it as positive. If COVID is not there, it has nothing to amplify, so it’s negative or not detected,” Hirschhorn said.

 Betsy McLaughlin carries samples from a refrigerator, where they've been kept cool while waiting for testing, to a colleague.

“These machines are interfaced with our electronic health records, so when the results are done, they immediately pop off into the patient’s health record, and you’ll get the results in MyChart.” That’s a change from the early days of the pandemic, when the results had to be entered manually, a much slower process.

The simple step that can speed or delay results

These days, the speed with which test results arrive can hinge on whether a swab is labeled electronically or by hand – electronically is better – and something pretty basic: your name. “The most important thing that really plays into turnaround time issues is registration. When people register for a COVID test, when you put your name on a label, the most important thing you can do is to use your full legal name,” Hirschhorn said. 

“A lot of times, somebody will put a nickname – they're called a middle name instead of a first name. When that comes into the laboratory, we have trouble finding the patient and who that test belongs to.”

 A label on a test sample is scanned to get the patient’s name and information into the system before testing.

She encouraged people who bump into delays to play it safe. “I know that testing can seem really frustrating right now because everybody wants to know whether or not they have COVID. But I guess for me, the most important piece of advice is if you don't feel well, isolate yourself until you know whether you have COVID if you can. Masking with a high-quality mask has also been shown to reduce the transmission of the virus. 

“I know that's hard sometimes, given our lives, and some of us don't have the luxury of being able to take that time to be careful. And so, we also have masks and N95s, KF94s – are all really good choices because they're higher grade, and so they can help control the virus’s spread.”

Inside the Lab

Check out this video for a behind-the scenes look at the MUSC COVID-19 testing lab.

Original source can be found here.