Not a single person was unaffected, man, woman, child, they were lucky that the animals weren't affected. No matter how hard they tried no one could control their bladder or bowl movements, if you had to go you went right then right there. Many tried to find a cure, scientist tried to find a virus or mutation, but found nothing that their current science could do. Priests, nuns, shaman, and any other religious leader prayed to their gods or tried to use magic, but nothing happened and they eventually gave up.
Years pass and, with it affecting everyone, the incontinence was accepted. The smell wasn't as bad as people would expect, and some even liked it (weird huh), the diaper industry boomed as more and more people began buying diapers, and, since it wouldn't do any good, people stopped trying to potty train their children and bathrooms were turned into changing stations.
Their were many cases were people had to change in public and because of this wearing less cloths became more acceptable in some places people only wore diapers, or even nothing (that's right not only do nudist still exist but their actually more common, weird huh).