White House coronavirus task force coordinator Dr. Deborah Birx said the statistic she watches closest is the test positivity rate because it is “the most sensitive indicator” of how the coronavirus situation is unfolding at any particular time and place.
The test positivity rate is the percentage of people who get tested and turn out to be infected with the virus.
“It only has to go up a tiny bit. So let's say you had 3% test positive, and then the next week you have 3.3%. That is when to start really watching,” Birx told Fox News’ Bret Baier Wednesday.
She said every Monday each governor gets an approximately 10-page report with that information.
“We think that's the earliest indicator. That's why we show that at county level, at metro level, in small cities and large metro areas, as well as the state level — so that every governor and every mayor and every health commissioner can really understand what we're seeing in their state. And so that we can really provide recommendations to the states on how best to control this virus,” she said.
Birx said the country had to change its testing strategy to improve the turnaround time for test results — especially the hardest hit states, which also have the longest turnaround times.
“We have three states that are equivalent to what the worst conditions were, as far as number of tests required, with New York…. So now we need three times, really, the number of tests that we had before. And so we're really working to increase pooling. We know that can dramatically increase our through-put,” she said.
“Really, we need the Northeast and the Midwest, that have those very low test positive rates, to move to pooling so that those tests can be moved to the South, the Southwest and the West,” she said.