COVID-19 Presents Lab a Big Challenge

The laboratory team at Johns Hopkins All Children’s worked to ramp up its in-house COVID-19 testing capacity. 

Mandy Gustafson, lead medical technologist for microbiology, performs COVID testing in the laboratory at Johns Hopkins All Children's.

Mandy Gustafson, lead medical technologist for microbiology, performs COVID testing in the laboratory at Johns Hopkins All Children's.

Published in Johns Hopkins All Children's Hospital - Spring 2021

One year ago this month, we began to understand the reach of COVID-19. This is part of a periodic series at on various ways the pandemic has made an impact.

Yanice Maldonado decided to put the cold Connecticut weather behind her and move near family in Florida.

She had experience as a microbiologist in an academic medical setting and set her sights on a job at Johns Hopkins All Children’s Hospital. “I was looking for some place well known with good values,” she says. “I thought, I know Johns Hopkins.” So, she started her new job.

It was February 2020.

Little did Maldonado know that just a month into her new job, she would be called upon to supervise testing related to a pandemic. Shortly after starting as microbiology manager, she also took on a role leading the immunology team. Those are the primary lab groups responsible for COVID-19 testing at the hospital.

“I love a challenge, so I went with it,” she says, a year after testing for the coronavirus became part of her daily routine.

Validating Testing Platforms

Initially, Johns Hopkins All Children’s was only testing symptomatic patients and employees. The hospital halted elective surgeries and the first tests were sent to the Health Department or Tampa General Hospital as Johns Hopkins All Children’s ramped up its in-house testing capacity.

“It was very challenging,” says Vicky Harris, pathology and lab director at Johns Hopkins All Children’s. “When the pandemic first started, it was communicated that the virus wasn’t really an issue with children, so freestanding pediatric hospitals had greater obstacles obtaining testing supplies. Vendors/manufacturers rationed supplies and adult hospitals in the pandemic epicenters received their allotment first.” 

As Sarah Dodge, a medical technologist in the immunology lab, ran tests to validate the first platform, she ran into a problem of not having enough positive samples.

Most of the early tests at Johns Hopkins All Children’s were negative, which was good for the patients but made it difficult to validate testing platforms. Proving a testing platform works requires a positive clinical sample, which Maldonado’s team was able to obtain from The Johns Hopkins Hospital, which had many COVID-19 cases in Baltimore at the time.

“The validation had to be stringent because these were all emergency use authorization (EUA) tests,” Maldonado says. “So, we needed positive COVID samples. Baltimore sent some positive samples.”

By March 30, Jimmy Lenas, another medical technologist, was trained to perform patient testing and Johns Hopkins All Children’s was conducting testing in house on its first validated platform. Over the course of the rest of 2020, the team validated more platforms, finishing the year with five.

How It Works

A year into the pandemic, many are familiar with the first stage of testing, a nasal swab that collects the sample. But what happens next?

When the sample comes to the lab, the first step is triage to determine what testing platform is appropriate. The tests are complex and supplies for the various platforms — particularly the faster ones — are limited. Most tests are done in batches, generally up to 34 at a time for the slower tests and up to 16 for some of the tests that must be run more quickly. Once a batch is started, most platforms don’t allow you to add samples until the test is complete, so test prioritization is key.

For instance, a trauma patient who needs treatment quickly might receive a “stat” test that produces quick results while a patient who is scheduled for surgery the next day might receive a slower test that has more plentiful supply.

“That’s our first step, deciding what platform and what time frame,” Maldonado says. “The tests are highly complex and require a certain incubation period.”

Once the testing platform is chosen, the analysis is performed in a negative pressure room, which allows outside air in but restricts air that flows out so that it must pass through a filter. This is a common technique to contain infectious viruses. Lab members performing COVID-19 testing generally wear an air-purifying respirator called a PAPR, which keeps them safe but can be cumbersome to wear for several hours. A routine COVID-19 test takes about four hours, an urgent one two hours and the fastest “stat” tests can be completed in about an hour.

“It takes a long time, which can be uncomfortable while wearing the respirators and other PPE,” Maldonado says. “It’s been challenging for the staff. It’s cumbersome to work with the personal protective equipment that is required, but they’re doing it, and they’re doing great at it.”

Maldonado credits her team with incorporating COVID-19 testing into an already full workload of other necessary sample analysis for the hospital’s patients.

“This pandemic showed everyone how important the laboratory is for patient care and diagnosis,” Harris says. “Without the laboratory and the ability to test for COVID-19, the hospital could not have responded and resumed services as usual.”