Blueberry Juice Contagious?

For the brief time I've been involved with this community, I've seen an odd trend among blueberry inflation. In a lot of interpretations, the berry juice seems to be contagious, with ingestion or even simple contact with the skin causing the poor person to plump pleasantly proper.

I enjoy it as much as the next person. My question is, does anyone know where that idea even originates from? Obviously there's nothing in the og story about it spreading, so someone in the community had to come up with it, right? I simply have no idea where it would've started since it seems to have been somewhat pervasive for a loooooong time.