(06-21) 15:39 PDT SAN FRANCISCO -- Since the AIDS epidemic, awareness of sexually transmitted diseases seems embedded as a Bay Area cultural norm. Condoms significantly decrease transmission rates of the most life-threatening viruses, HIV and hep B and C. But it's not foolproof - statistics on liver disease show that 60 percent of hepatitis carriers acquired the virus by means other than sexual intercourse, such as recreational IV drug use or by receiving a tainted blood transfusion. Screening with Pap smears, including newer viral DNA testing, allows for more accurate and sensitive identification of those women who are at significantly elevated risk for cancer because of having acquired high-risk subtypes of HPV. When it comes to viral STDs, the devil is in the details. Since it appeared in print, this column has been corrected to accurately reflect which agency recommended HPV vaccines for boys.