Does washing clothes rid of bacteria that could cause re infection such as underwear or mastirbating into a washed sock that was used before while inf?

Hygiene: Washing clothes will not rid them completely of bacteria but will reduce the amount of bacteria on them reducing the risks of being exposed to a significant amount of bacteria (innoculum) that might cause an infection. The second part of your question re masturbating into a sock was cut off so you may wish to resend this as a separate question and one of the docs will try to answer this.

No risk: Washing with soap or detergent will remove or kill any bacteria or viruses likely to cause harm. There would be no risk of infections because of prior mastutbation, even if the masturbating person had an STD. STD germs are not transmitted by skin contact etc, only by having sex with an infected person. For sure if the item had been laundered there is absolutely no risk of any kind of infection.