nothing is 100% except abstinence... condoms are good for preventing HIV and most other STD's. Warts can be contracted with condoms becuz your partner could have a wart where the condom does not cover.. learn about what they look like so that you can spot them. Not to scare you but 80% of the pop carries this virus but only 30% ever develop the warts so many go around spreading the virus without even knowing it..and there is no test for men..so take the precautions and wear the condoms every time.

good luck
CBU