WASHINGTON -- Future COVID-19 tests will also be able to test for influenza A and B, according to Trump administration "testing czar" Adm. Brett Giroir, MD.
"Most of these tests will be multiplex by flu season -- one PCR test will diagnose both influenza A/B or COVID," Giroir, who is assistant secretary for health in the Department of Health and Human Services (HHS), told ľֱ during a phone call with reporters Thursday afternoon. "Everybody's going down that developmental pathway."
He urged everyone to get their flu vaccine in order to lessen the spread of influenza, which kills 30,000 to 70,000 people each year. "I'm a pediatric ICU doctor; I lost children from influenza every single year of my career, and most of those children -- the great majority -- didn't get vaccinated," he said. "That's a tragedy."
Giroir also gave an update on COVID-19 testing nationwide, noting that 51.7 million tests have been administered to date, and that an average of 770,000 tests per day are being conducted. The average positivity rate over the past week stands at 9.08%, Giroir said, adding that the administration "is very concerned about outbreaks occurring across the country, particularly in the Sun Belt states." He tried to put a positive spin on the situation, however, noting that "our public health measures are starting to make a difference and we are making progress ... We are starting to see the 7-day rolling averages of cases starting to turn downwards," although "no one is declaring victory about this."
Half of the tests now being done are administered either at the point of care -- with a turnaround of 15 minutes -- or at local hospitals, where "in general, we know that's done on one shift, or within 24 hours in general," he said. The other half is performed by major commercial labs, where "the average turnaround time is 4.27 days." Giroir added that this number "is not as bad of a number as many people talk about, it's up 0.8 days from what it was in June, but we're trying to drive that down" through use of surge testing sites to reduce commercial laboratory burden, and through "pooled" testing, in which the lab combines samples from a group of people in a single test. Pooled testing increases efficiency by 20%-to-30% in the labs that use it, he said.
The administration also is moving more and more to point-of-care testing to reduce demand on commercial labs. "This week we sent 654 point-of-care testing machines to 635 nursing homes, and that's 196,000 tests," said Giroir. "Over the next 2 to 3 weeks, we'll be sending instruments to an additional 1,790 nursing homes; that includes an additional over 806,000 tests." Overall, he said, based on manufacturer projections, "in August, we expect the availability -- it doesn't mean we're going to use them all -- of approximately 51 million tests, of which 13 million will be point-of-care; in September, it's approximately 65 million, of which we expect approximately 20 million to be point-of-care."
In response to a question from ľֱ, Giroir acknowledged that the point-of-care tests were less sensitive than those performed in clinical labs. "Almost every test has a tradeoff, so it has to be applied in the right surroundings and the right venue," he said. "The point-of-care tests in general have slightly less sensitivity than the laboratory-based molecular tests, but new data is showing that may not even be true, that we may have one or two of these that are equivalent to those. So the sensitivity might be a little bit less, meaning you have a potential for more false negatives. Every test has a potential for false negatives, including the laboratory tests."
So if the point-of-care tests are less sensitive, why is HHS still sending them to 15,400 nursing homes? "When you do the mathematical analysis with everything built in, if you have a point-of-care test that's a little bit less sensitive, that beats a more sensitive test that you have to wait 2 days for, every single day, because you can act on that right there," he said. "Ideally you have a 100% sensitive, 100% specific test that's available in 2 minutes; we don't have that, so we're applying this ecosystem in the optimum way for the use case that we have."
As for testing supplies, such as swabs and media, "we had a huge mobilization to get where we are, states tell us what we need every month and we send it," he said. "The federal government purchases that; they get four shipments to a central location once a week for that month. We rely on the states to make sure they're summing up their entire state needs."
Giroir was also asked about colleges and universities that are considering testing students before allowing them to return to school. "In general, testing people before going back to the university is not a strategy we recommend, because you're only negative for that one moment," he said. "You could be positive the next day, and it doesn't relieve any responsibility about wearing a mask and doing all those kinds of things."
In addition, "many universities we've talked to are doing a strategy which I think is much better -- doing surveillance, not diagnostic testing, but surveillance in their university research labs using excess reagents that would not burden the system," he said. "We've been working a long time to make this possible and support universities in doing this, and several universities are doing this exactly." One advantage of this strategy is that the university doesn't need an Emergency Use Authorization to do surveillance, which is done through pooled testing.