Figure 1.

Reinfection associates with more frequent testing at shorter intervals. The total number of tests (A) and the interval in days between tests (B) among the reinfection and convalescent group. The interval is days from the first positive result to the next positive test at least 90 days later in those with reinfection, and from the first positive to the last negative test at least 90 days later in the convalescent. The box plots show median and interquartile range. ∗∗∗ and ∗∗∗∗ indicate P ≤ .001 and P ≤ .0001, respectively, by the Mann-Whitney U test.