AILSA CHANG, HOST:
With the surge in new coronavirus cases in the U.S., demand for testing has also risen sharply, and labs are falling behind. Quest Diagnostics, one of the nation's largest testing companies, says it now has a turnaround time of four to six days to run a test for someone who is not in a hospital. Long lines are forming at testing sites from Denver to New Orleans, and that delay means infected people may be spreading the disease for days without even knowing it. Joining us for the latest on this is NPR science correspondent Richard Harris.
RICHARD HARRIS, BYLINE: Hi, Ailsa.
CHANG: Hi. I mean, testing has been a struggle since the earliest days of the coronavirus. So where exactly do we stand now?
HARRIS: Federal officials boast about the sheer numbers of tests that are getting done. It's now more than 600,000 on an average day, which is certainly a big step up from a few months ago. But...
HARRIS: ...That's straining the capacity of the system. And when you consider that public health officials say they need a lot more testing in order to really get ahead of the epidemic, it really shows how much more work there is to go.
CHANG: And is it simply that the huge demand is creating these problems?
HARRIS: That appears to be the major driving factor. But you know, there are still problems with supplies. Yesterday in a telephone briefing, Admiral Brett Giroir from the White House coronavirus task force said from the federal perspective, the supply system is working.
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BRETT GIROIR: The states are getting all the upstream supplies that they asked for - so tubes, the media, swabs. Basically, they put in their order to the federal government. They get it delivered to a single site every week within the states. And we are meeting everything that they're asking for.
CHANG: We are meeting everything. Well, is that what you're hearing from labs?
HARRIS: Well, there seems to be a breakdown somewhere because I talked to Mark Birenbaum, who's the executive director of the National Independent Laboratory Association. This represents community and regional labs. And he says those labs still don't have reliable supplies.
MARK BIRENBAUM: We've had trouble identifying who has those supplies in each state and how our labs can access that, how it's being allocated. We asked the task force to give us the name of each state contact that the supplies were sent to, and we can't get that list.
HARRIS: And Birenbaum told me that some labs could actually run more tests, but they aren't getting enough samples to run. Others need particular ingredients that may or may not be available, depending upon the day. In New Orleans, for example, testing is constrained because the city can't get supplies to run the specific testing machine that they use.
CHANG: I mean, obviously, these testing delays are frustrating to people who have to wait for hours in line and then have to wait many days to get their results. Can you just talk about the health risks of all of that?
HARRIS: Right. One of the biggest concerns is that people are often most infectious just in the first few days before symptoms appear. So if they've gone to go get a test after learning that they've been in close contact with somebody who has COVID-19, by the time they get their results, it's really too late. Here's Alison Galvani at the Yale School of Public Health.
ALISON GALVANI: You will have missed your window of opportunity to curtail their transmission. It makes it much more challenging to control the disease. It's a gap that we need to close in order to bring this disease under control.
HARRIS: And Galvani and her colleagues have just published a rather sobering paper showing that it really won't be possible to control the epidemic simply by isolating people who are already showing symptoms. Health officials really need to do rapid contact tracing and rapid testing to find cases as early as possible, and that's just really not happening right now in a lot of places.
CHANG: That is NPR's Richard Harris.
Thank you, Richard.
HARRIS: Pleased to be with you.
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