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By Ben Conarck and Daniel Chang
Florida’s coronavirus summer has felt like deja vu for public health experts worried about a testing system once again unable to keep up with surging cases and demand.
Like the rest of the country, the Sunshine State has relied on commercial labs to perform ever-increasing numbers of labor intensive molecular tests to detect COVID-19. An early summer wave of people seeking the tests created a bottleneck of results with up to two-week delays across the state.
That forced the Florida Division of Emergency Management to pivot to new providers and less sensitive tests earlier this month, reducing wait times to less than a week for many.
But that’s still too long to wait for a test result, experts say. The delays have made results largely meaningless and crippled the Florida Department of Health’s efforts to trace and isolate the contacts of the thousands of people testing positive every day.
A new generation of less sensitive but faster COVID tests, cheap to produce in mass quantities, could change that. More than a dozen companies are developing the tests, which require no specialized equipment and have rapid and easy-to-read results. The tests _ which measure a protein called an antigen that signals an immune response to the virus _ first started hitting the market in May. Florida began using them this month at state-run testing sites.
Though most of the tests being developed are still awaiting federal approval, they use a variety of methods _ saliva samples or nasal swabs _ and can produce results in as little as 15 minutes. Florida plans to open two new sites _ for rapid antigen testing only _ in Miami-Dade in early August.
“We have to change our mindset from diagnosing if a person has an infection to: Are they infectious? And that’s a different world,” said Eric Topol, head of the Scripps Research Translational Institute in San Diego.
Floridians returning to work or school could learn quickly and with little expense if they are asymptomatic but could potentially spread the disease, Topol said.
“These rapid tests are perfect for that, and that’s what we have to fix. We have to get out of this mode that I’m diagnosing infections, because that’s not really important. A lot of the people who have the virus have such low loads … that they’re not going to pass it on.”
The idea of willingly overlooking people with lower viral loads, who are thought to be less contagious, in order to more effectively find the more contagious cases was discussed by Harvard T.H. Chan School of Public Health researchers earlier this month and has gained steam in light of all the testing delays this summer.
On Tuesday, rapid COVID-19 testing in development moved further toward reality. The U.S. Food and Drug Administration, which must approve all diagnostic tests before they can be sold to the public, issued new guidance for manufacturers to develop tests that can be performed entirely at home or in other settings besides a lab, such as offices or schools, and that could be available without a prescription.
“We hope that with the innovation we’ve seen in test development, we could see tests that you could buy at a drug store, swab your nose or collect saliva, run the test, and receive results within minutes at home, once these tests become available,” FDA Commissioner Stephen Hahn, who is also a physician, said in the announcement. “These types of tests will be a game changer in our fight against COVID-19 and will be crucial as the nation looks toward reopening.”
Jared Moskowitz, the director of Florida’s Division of Emergency Management and the state’s COVID testing czar, said he is a proponent of “potentially sacrificing a little bit of sensitivity for speed so that you can catch the more contagious.”
He said his department is waiting for the technology to be made more widely available, maybe as soon as September.
“If it takes 10 days to get a (test) result, that makes contact tracing irrelevant,” Moskowitz said.
THE NEXT GENERATION OF COVID TESTS
Dino Mosquera, a pharmaceutical researcher who lives on Miami Beach, took a COVID test at a Department of Health mobile site on 73rd Street and Collins Avenue on July 24. There was no wait, and he completed the visit in 20 minutes. He received his negative test results Wednesday morning _ a five-day wait.
That’s within the time frame the health department promised the results, Mosquera said, and it’s an improvement from the two-week wait times that became commonplace late last month.
But in a few weeks, Mosquera is going to need a faster result. He said he is planning to travel in mid-August, and will need a negative test result that is not older than 72 hours to board his flight.
“It doesn’t have maximum value if I can’t get the results within three to five days like they said,” he said.
There are at least 20 different companies working on rapid COVID tests that would be cheap to produce and, administered frequently, be able to detect when a person is contagious.
Topol, of the Scripps Research Institute, said the companies are using different approaches. Some are using a gene-editing tool called CRISPR to detect viral DNA sequences, and others detect antigens, which are molecules signaling an immune response to a virus. None require a lab to process results, dramatically improving the speed for results.
“None of this waiting a day stuff,” Topol said. “We’re talking about less than an hour, and they don’t require any machines.”
The FDA requires COVID-19 tests to meet accuracy standards of 80% or better, depending on whether the person being tested is symptomatic.
Ashish Jha, a physician and director of the Harvard Global Health Institute, said that although the rapid tests are less sensitive and will miss some people who are positive, that would still be far better than the current system, which is already missing large swaths of infections.
Look no further than Florida, Jha said, which has been reporting about 9,000 to 10,000 cases a day with a positive test rate well above the recommended 5%. That’s a clear indication that the state is not testing enough people to understand how many people really have it.
“We’re only getting about one out of six cases,” he said. “When people say, ‘Well with antigen tests you’re going to miss cases,’ I’m like, ‘Am I going to miss more than 80 to 85% of cases? I don’t think so.’ You always have to compare it to the alternatives.”
FLORIDA PIVOTS TESTING
Moskowitz said the state’s first two rapid testing sites will open in Miami-Dade by early August, one at Collins Park in Miami Beach and the other at a location in Miami yet to be determined, he said. Both sites will use an antigen test called “Sofia SARS Antigen FIA” manufactured by the Quidel Corporation of Ohio. It’s one of two antigen tests for COVID-19 approved for use by the U.S. Food and Drug Administration.
In the current crisis, Moskowitz has shifted the state Division of Emergency Management’s testing away from large private labs and toward a handful of providers who have been quicker to process results.
That shift has improved wait times, he said, but what Moskowitz says he really wants are self-contained rapid tests that won’t require the laboratory and supply infrastructure needed for the nasal swab tests that make up the “overwhelming amount” of Florida’s testing, Moskowitz said.
“I hope as I can get my hands on more machines that I can bring more rapid testing to the public,” he said. “There’s no doubt faster results will allow for faster contact tracing.”
Moskowitz added that Americans are “not built to wait hours to get tested and days for your results.”
“If you can get an Amazon package faster than you can get test results,” he said, “that’s not successful.”
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