It is important to discuss sexual history and health matters with partners frequently and definitely before having sex. • If a partner has signs or symptoms of an STD, avoid sex with them until they test negative. • Reduce number of sex partners. • Use a latex condom when having sex, especially with a new partner or a non-exclusive partner. • Use good hygiene both before and after intercourse. • Do not share towels or clothing. • There are vaccines for some STDs (hepatitis B, HPV) that can prevent infection.   Regular testing is the only way to know for sure that you have not acquired an STD.