Trump likes to brag about the number of tests conducted in the US. But the truth is most of those tests were largely useless as the results have been delayed an average of 7 days. If results are not available with a day or two, it becomes impractical/impossible to effectively contract trace. And those people who are positive won't isolate quickly enough. So receiving a positive result a week later means that transmission has likely already occurred and spread greatly with no way to contain that.
(Biden should have figures on what % of US tests provided results with 2 days, which is when epidemiologists say is the effective range).
In China by late March, test results were available within 4 or 5 hours, though some areas provided next day results. They used a cheap, quick test, not the highest reliability but fast results, so that a 2nd test could be administered easily as needed.
Biden and the Dems should be ready to counter Trump touting the number of tests, a misleading and useless metric.