What I do is I run with the mod debug mode on and change their name. for example. "Aiden (Bitten)" and based on my settings ill mark a date for them to die. If I have bites to kill in 2-3 days then Ill set a date 2-3 days out same for weeks. Finally when their day is up I use mod debug mode to "murder and infect". It would be nice if they didn't heal from bites but I think this is fix to your problem until they don't heal from bites. Hope this helps