Box plot of single passage times for virus isolate #1, #2/3, #4 & #5 during experimental set-ups A–F as indicated on the x-axis.

<p>The solid red horizontal lines indicate the respective median passage times, whereas the boxes surrounding them indicate the range encompassed by the 25^th and 75^th percentiles. The whiskers denote the most extreme data points, which are not considered outliers and the black dots indicate outliers. A: Viral passage times for isolate #1. B: Viral passage times for isolate #2&3 (combined). C: Viral passage times for isolate #4. D: Viral passage times for isolate #5.