(E) Sporozoite track straightness, the ratio of displacement to track length of P. falciparum sporozoites moving in mouse dermis, human skin ex vivo, and human skin graft, at 5-10 min post intradermal injection. Data is displayed in box and whisker plots with horizontal line showing the median and the whiskers extending to the minimum and maximum values. Comparisons showed statistically significant differences in track straightness between the human skin graft and both mouse skin (****p=0.0001) and human skin ex vivo (****p<0.0001) using Tukey's multiple comparisons test. A varying number of tracks were processed for each environment: mouse skin: 17 videos, 822 tracks; human skin ex vivo: 12 videos, 761 tracks; human skin graft: 9 videos, 718 tracks. 