(A-D) Pooled patient samples at high (5.7x104 copies), medium (3.6x102 copies) or low (2x101 copies) concentrations (A, B), or stocks of SARS-CoV-2 WA1 (C, D) were subjected to -80ºC storage interrupted by (A, C) successive freeze-thaw cycles or (B, D) storage at 4ºC, room temperature (RT) or 37ºC for the indicated time periods. N=1 for A, B. For C and D datapoints are from 3 different viral stocks titered in duplicate and plotted as mean with error bars plotted as +/- SEM. For C raw values are plotted while values are normalized to starting titer for D. Limit of detection for infectious titer in C is indicated by a dashed line. 