Important to note that both of these studies are on pre-Delta variant patient sets, so unlikely to represent current real world impact on transmission from vaccination. This [0] is the most recent I've seen, and it suggests the reduction in transmission against Delta is smaller and wanes rapidly, even with the mRNA vaccines.

[0] https://www.medrxiv.org/content/10.1101/2021.09.28.21264260v...