Ditto on the comment about synthetic and, yes, do read the prior thread.

I would add to that that I frequently hand wash, always (whether machine or not) wash inside out, rinse A LOT and dry them, when I can, outside in the sunshine. There is nothing like real fresh air and sunshine to make things smell good and do any last disinfecting needed. Avoid that dryer like the plague, though, since it will ruin the shorts.