Doing laundry

So I live at home still as I am in high school still and I am a female. But I was wondering since all of our family puts our laundry in one laundry basket in the bathroom so it's all mixed in( my brothers a underwear would be mixed in with mine) and I do my own laundry sometimes but sometimes I don't. But if my brother had an std or sti could it transfer from his underwear to mine while being in the laundry basket together? He's not a virgin and I'm not.