01-31-2016, 02:29 AM
I imagine the societal effects of human disease/infection resistance are somewhat similar to the existence of vaccinations and modern medicine - child death rates are very low which in turn means families tend not to have a lot of them (usually there is a burst followed by decline AFAIK, but unlike vaccines there was no acclimation period where people had as many kids as before [resulting in huge families] - people have always been like that in AS). Likewise, childbirth is safer.