Testing will be a key factor in how quickly Florida raises the curtain on a more customary lifestyle. “We need to expand testing beyond what we’ve already done,” Gov. Ron DeSantis said Wednesday in outlining Phase 1 of the reopening plan. In mid-January, there was no test on these shores for COVID-19. Now more than 50 manufacturers have kits in the marketplace. “To develop a test for a given disease sometimes takes years,” said Dr. Michael Lauzardo, deputy director of the University of Florida Emerging Pathogens Institute. “This is being done in weeks."
The original: First developed by the Centers for Disease Control and Prevention in January, the test involves inserting a 6-inch-long swab deep into a patient’s nostril and rotating it. The coronavirus is most reliably found in the nasopharynx, a cavity that sits just above the throat. Lab testing extracts viral genetic information from the swab and compares it to the COVID-19 sequence. Even with recent advances, it’s still the primary method of learning whether someone is actively carrying the coronavirus. Last week, the FDA authorized the first home-kit swab test.
Branching out: UF Health researchers recently tested more than 2,000 asymptomatic people at The Villages Polo Club as part of a study to look for a different set of genetic markers, or “primers,” than CDC tests were seeking. Swabs still were applied up the nose, but testing sought primers identified by European Union researchers as most specific to COVID-19. “Over time we’ll learn which might be more accurate and therefore a better test,” said Lauzardo, who coordinated The Villages study. Other efforts elsewhere are testing different primers, he added.
Days to minutes: As researchers fine-tune detection technology, testing machinery already in the market has been adapted to search for COVID-19 primers. Cepheid’s GeneXpert machine can deliver results in 45 minutes; Abbott Laboratories has one that works in five. “Some of these (machines) have existed for 10 years,” Lauzardo said. “Most hospitals have the GeneXpert machine, but they did not have primers for this organism.” Several experts caution there can be a trade-off — faster results don’t necessarily translate to better accuracy.
Spit, please: A saliva-based test developed by a Rutgers University team got the FDA’s green light earlier this month, requiring only that patients spit into a collection device. Not only is it less invasive than a swab, it would lessen exposure for health care workers. That said, questions remain whether saliva tests will be as accurate as those via swab. “Saliva is not a traditional specimen source,” said Dr. Jane Hata, director of the Mayo Clinic’s microbiology lab in Jacksonville. Consistent sample collection will be the key, she added.
Antibody tests: These tests look at blood for signs of antibodies that developed to fight COVID-19. It’s not suitable for determining whether someone is actively fighting the coronavirus, but should prove useful in learning how many were exposed but showed no or mild symptoms. It also may serve as an indicator that a person has developed at least some immunity. More than 180 manufacturers have told the FDA they’ve validated tests; four have been approved. One test allows people who meet certain criteria to buy it online and schedule to have blood drawn.