As the number of COVID-19 cases continues to rise both locally and nationally, states have been attempting to speed up testing procedures and make them more widely available and accessible.
But with the recent spike in cases, hospitals, cities and states across country are still lacking in the number of tests – preventing potentially infected people from knowing when they are carrying the virus and should not be in contact with others.
One potential solution that has been discussed worldwide and most recently broached by Stanford University researchers is the concept of mass testing. In an article published in SIAM News, three Stanford researchers wrote about the possibility of accelerating testing for COVID-19 by pooling samples and mass testing them – saving time and money. Last month, Stanford received permission from the U.S. Food and Drug Administration to pursue pooled testing.
By using as little as 10 test kits, researchers contend it can determine whether a large group of people have COVID-19. As David Donoho, professor of statistics at Stanford, describes it, the process is like solving a Sudoku puzzle. The concept involves taking each person’s specimen, dividing it into three and using it three different ways to form a series of pooled specimens. Each pool sample contains material from seven different people. Once all the pooled specimens are tested, researchers know which patients belong to which pool, along with which pools produced positive results. With the that information – knowing what’s in the pool and who’s in the pool – it comes down to using math concepts.
“In that way, you don’t have one test for every patient,” Donoho said in an interview with the Town Crier. “You have one test for every pool, and that saves a great deal. By solving a math puzzle, you save a lot on the number of tests that you have to do, and you’re just using your brain.”
Donoho added that a majority of people being tested will be negative, meaning that it is economically prudent to be saving on testing.
“And that’s exactly what group testing allows,” he said.
Jump-starting the economy
Similar methods have been used throughout the course of history, beginning in World War II when blood samples were pooled to check for sexually transmitted diseases. It has also been used to test flocks of animals.
“It’s been used many, many times,” Donoho said. “It’s just each different disease has a different test, and you have to understand how it can be used productively with that test.”
Currently, research out of Israel shows that specimens from up to 32 people can be pooled, and it would still be possible to detect the sample of one person who is positive for COVID-19. Mass testing would allow for the economy to restart faster, giving businesses, schools and hospitals the opportunity to test certain groups of people such as health-care workers or nursing home residents more frequently.
“The more you test, the less disease you will find,” Donoho said. “As soon as somebody is identified and they don’t spread the disease, there’s less happening.”
Donoho said the United States has already built an incredible amount of infrastructure to increase its testing capacity. But he cites Noble Prize-winning economist Paul Romer, who said the country should ideally be testing every person every two weeks. For that to happen, testing needs to increase by a factor of 20. Donoho believes to achieve that, the country needs to double its infrastructure and then commit to group testing.
Only then would the amount of testing be sufficient to match demand, and lead to a substantial change in being able to reopen the economy.
“Many people live paycheck to paycheck,” Donoho said. “They need the economy to open. Children cannot learn nearly as well nearly as well when they’re sitting at home, and there’s no teacher or classmates. The evidence is there. You need to get the economy going again.”