WASHINGTON - Long delays in getting COVID-19 test results across the United States is undercutting their usefulness, said Director of the US National Institutes for Health Francis Collins on Sunday.

"The average test delay is too long," Collins said in an interview with NBC. "And that really undercuts the value of the testing, because you do the testing to find out who's carrying the virus and then quickly get them isolated so they don't spread it around."

Collins said the US government must invest in new technologies in order to keep up with the testing demand.

"We need to do things that are more on the spot," Collins said. "There's a number of new technologies that are coming along that look very promising in that space. We need to invest a lot of money, and the government is willing to do so, in scaling those up."

The US Food and Drug Administration (FDA) issued an emergency use authorization (EUA) on Saturday to Quest Diagnostics that allows pool samples from up to four individuals to test for COVID-19.

The Quest test is the first COVID-19 diagnostic test to be authorized for use with pooled samples.

"This EUA for sample pooling is an important step forward in getting more COVID-19 tests to more Americans more quickly while preserving testing supplies," said FDA Commissioner Stephen Hahn.