Genitally-located HPV rates are identical in sexually active and non-sexually active populations

https://www.ncbi.nlm.nih.gov/pubmed/8389707

...and can be spread by objects with zero contact.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3532331/

Most cases of syphilis worldwide are from nonsexual contact

https://en.wikipedia.org/wiki/Yaws

Ghonnorea can be spread by objects with no contact.

https://www.ncbi.nlm.nih.gov/pubmed/17961874

...and this is not only true of chlamidia, but most cases worldwide are spread with no conatct.

https://www.ncbi.nlm.nih.gov/books/NBK28455/

So...

STD's would instantly become a much bigger concern for both kids and pedos, wouldn't they. Just a reality that should not be an unforeseen surprise if the day ever arrives.

Probably not. While sexual contact is a form of contact, the total absence of contact is also contact. Ever touch any physical object? You... might as well fuck everyone who's been anywhere near it. Seriously.

https://www.ncbi.nlm.nih.gov/pubmed/2880894

Here's a ref for object-driven herpes exposure. Which is a general skin condition otherwise transmitted by skin contact, not an "STD."

So... there's no reason to think rates would change, and almost all transmission worldwide is nonsexual. Any contact - including no contact, but contact with object residues, which should scare the living shit out of any preschool or daycare operator - is entirely the same.

So... nope, buddy. The western habit of shaking hands is probably far more dangerous.