FIGURE 4.

Merkel cell polyomavirus (MCPyV) and HPyV6 DNA loads on the forehead and the hand of individuals without and with short-term (A,B) and long-term (C,D) persistence. Viral DNA loads (Y-axis) were expressed as viral DNA copies per betaglobin-gene copy. Boxes represent the interquartile range with the median. Whiskers are vertical lines ending in horizontal lines at the largest and smallest observed values that are not statistical outliers, i.e., values more than three IQRs from the end of a box are labelled as extreme, denoted with an asterisk (*) and values more than 1.5 IQRs but less than 3 IQRs from the end of the box are labelled as outliers (o). (A) MCPyV and (B) HPyV6 baseline viral DNA load distribution of individuals without (left box plot) and with (right box plot) short-term persistence in collection period-1. The differences in viral DNA loads between individuals without and with short-term persistence were significant for both locations and both viruses [p < 0.001 for forehead (n = 109) and hand (n = 109), respectively; independent-samples Mann–Whitney U test]. (C) MCPyV and (D) HPyV6 median DNA loads over collection period-1 of individuals without (left box plot) and with (right box plot) long-term persistence. The differences in viral DNA loads between individuals without and with long-term persistence were significant for both locations and both viruses [p < 0.001 for forehead (n = 59) and hand (n = 59), respectively; independent-samples Mann–Whitney U test].