Is obesity contagious?
Yes (in the usual health prevention sense of “reduce the risk of”, not in the strict sense of “pose an absolute bar to”).
I have.
The general vaccine effects that it reduces likelihood of contagious infection seems to be very true of Delta, as does the effect that it reduces the length of contagious infection appear to remain. The effect that it doesn't seem to have with Delta that it had with some previous variant is reducing viral count in breakthrough infections compared to nonvaccinated infections.
The media, on the basis of “if it bleeds, it leads” and “man bites dog news, dog bites man not” has highlighted the science relating to the absence of the last effect, but not as much that relating to the presence of the first two.