Houston, November 22
Testing half the population weekly with inexpensive, rapid-turnaround COVID-19 tests can drive the pandemic toward elimination within weeks even if the tests are significantly less sensitive than gold-standard clinical diagnostics, a new study says.
The research, published in the journal Science Advances, noted that such a strategy could lead to “personalised stay-at-home orders” without shutting down restaurants, bars, retail stores and schools.
According to the scientists, including those from the University of Colorado at Boulder in the US, the sensitivity levels of the different types of COVID-19 tests currently used across the world vary widely.
Antigen tests require a relatively high viral load—about 1,000 times as much virus compared to the PCR test—to detect an infection, they said.
Another test, known as RT-lamp can detect the virus at around 100 times as much virus compared to the PCR, the study noted.
The scientists added that the benchmark PCR test requires as little as 5,000 to 10,000 copies of the viral genetic material, RNA, per milliliter of sample—meaning it can catch the virus very early or very late.
“Our big picture finding is that, when it comes to public health, it’s better to have a less sensitive test with results today than a more sensitive one with results tomorrow,” said study lead author Daniel Larremore from the University of Colorado at Boulder in the US.
“Rather than telling everyone to stay home so you can be sure that one person who is sick doesn’t spread it, we could give only the contagious people stay-at-home orders so everyone else can go about their lives,” Larremore said.…