A health care worker carries a stack of clipboards at a Covid-19 testing site on Monday, July 6, 2020, in Homestead, Fla.
Washington CNN  — 

The director of the National Institutes for Health said on Sunday that long delays Americans are seeing across the country in getting coronavirus test results is undercutting their usefulness.

“The average test delay is too long,” Dr. Francis Collins said Sunday on NBC’s “Meet the Press.” “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.”

As Covid-19 continues to surge in the US, some states, labs and public health departments are warning that turnaround times for diagnostic testing have slowed.

The challenges, which stem in part from persistent obstacles in the test supply chain, underscore that while overall US testing capacity has multiplied, the nation’s health system still struggles in some regions to rapidly detect the spread of the virus.

Despite federal efforts to support testing in some cities and regions, major diagnostic companies said earlier this month that the growing demand for tests has in turn increased average wait times for delivering results. CNN previously reported results can now take an average of four to six days for the general population or in some states like Arizona up to three weeks.

Collins said Sunday that the 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.”

President Donald Trump has repeatedly argued against the value of widespread coronavirus testing, claiming that more testing creates more cases. He reiterated that claim on Sunday in an interview on “Fox News Sunday.”

“That’s because we have great testing, because we have the best testing in the world,” the President said of some states seeing an increase in coronavirus case numbers, later adding, “Cases are up because we have the best testing in the world and we have the most testing.”

Health experts have said that this is not the case, pointing to data that shows the percentage of people testing positive has also spiked indicating virus spread.

The White House is pushing back against Senate GOP requests to significantly ramp up funding for the Centers for Disease Control and Prevention for coronavirus testing and contact tracing.

Some Senate Republicans are pushing for more money for the efforts in the next round of stimulus spending, but the White House argues that there is sufficient funding still remaining from the March stimulus law, a source with direct knowledge of the matter told CNN on Saturday.

CNN’s Manu Raju, Lauren Fox, Kristen Holmes, Curt Devine and Naomi Thomas contributed to this report.