We're doing a lot less coronavirus testing

The U.S. is cutting back on coronavirus testing. Nationally, the number of tests performed each day is about 17% lower than it was at the end of July, and testing is also declining in hard-hit states.

Why it matters: This big reduction in testing has helped clear away delays that undermined the response to the pandemic. But doing fewer tests can also undermine the response to the pandemic.

By the numbers: At the end of July, America was doing more than 800,000 tests a day. This week, it's hovered around 715,000.

• Even as states with particularly bad outbreaks pull back on their testing, the proportion of tests coming back positive is still high — which would normally be an indication that they need to be doing more tests.
• In Texas, 19% of tests are coming back positive, according to Nephron Research. In Florida, the rate of positive tests is 18%, and in Nevada, 17%.

Yes, but: Experts have said reducing the demand for testing may be the best way to alleviate long delays, which made tests all but useless. And that appears to be working.

Driving the news: The Department of Health and Human Services estimated this week that nearly 90% of all tests are being completed within three days — a big improvement from turnaround times that had been stretching well over a week.

• Quest Diagnostics says its expected turnaround time is now 2-3 days, and less for priority patients. LabCorp announced a similar turnaround time last week.

What they're saying: “Reductions in testing are not concerning when you have an already low positivity rate that is flat or further decreasing.  But reductions in testing coupled with increasing positivity is disconcerting," said Duke's Marta Wosinska.

• "This means that a lot of viral activity is not being recorded just as we are trying to make critical decisions like whether to reopen schools.”

The bottom line: The U.S. is averaging 50,000 new cases a day, and that high caseload is ultimately why the demand for testing is more than the system can handle.

• We can't get our caseload under control without fast, widespread testing, but we can't achieve fast, widespread testing with such a high caseload.