Last week's revelation by the U.S. Centers for Disease Control that one-quarter of teen-age girls have at least one sexually transmitted disease came as no surprise to some southeast Michigan health providers, who say such an epidemic is the fruit of a widespread failure to teach teens about sex.

The study, released last Tuesday at a conference in Chicago, was the first of its kind on this age group. It found that 3 million teen-age girls nationwide have an STD, with human papilloma virus, which causes cervical cancer, the leading infection. It also found that nearly half of all black girls have an STD, compared with 20 percent of white and Mexican-American girls.

"Certainly the study just underscored what we've know for years - that teens need to know how to protect themselves against STDs and unintended pregnancy, and the way they do that is by real, live sex education," said Lori Lamerand, president and CEO of Planned Parenthood Mid and South Michigan.

Indeed, some of the studied teens identified sex as vaginal intercourse only, even though other forms of sexual contact can spread STDs.

"The first thing is I think they're in denial," said Dr. Natalia Turner, an attending physician at Children's Hospital in Detroit and clinical professor at Wayne State University's Division of Adolescent Medicine. "They think if they have sex, they aren't going to get pregnant and aren't going to get an STD. It's part of being mature enough to have abstract thinking."

Turner encourages parents to vaccinate their daughters against HPV and the study renewed calls by medical providers for widespread vaccination. The vaccine, however, is expensive and typically not covered by insurance. And some parents resist vaccinating their daughter against a disease that is only transmitted through sexual contact.

"It's all about HPV being sexually transmitted is what really blocks it," Lamerand said. "When parents say, `I'm not going to vaccinate my 14-year-old daughter because that's giving her permission to have premarital sex,' my jaw hits the floor."

HPV can cause genital warts as well as cervical cancer, but often has no symptoms. Chlamydia and trichomoniasis, the second- and third-leading infections, respectively, can be treated with antibiotics. The CDC recommends annual chlamydia screening for all sexually active women under age 25. It also recommends the HPV vaccine for all females younger than 26.

The astronomical rates of STDs among black girls are especially troublesome in Metro Detroit. The numbers reflect African-Americans' inequitable access to health care across the board, Turner said, adding, "Look at statistics for breast cancer - the mortality rate is much higher among African-Americans because they don't get mammograms and they don't get health care."

Lamerand agreed. "Health disparities among races is a given in our society, but it's unconscionable," she said. "Some of it is related to what happens in schools. Unfortunately Southeast Michigan, where most minorities live, is also where schools aren't addressing this with comprehensive education."

Turner said routine preventive health care with a physician who specializes in treating adolescents is key to teens' health and keeping them free of STDs.

"Preventive health care is what they really need. … But parents don't bring them in," she said. "At those appointments I explore how they're reacting with parents, school, community, a healthy lifestyle. If they come every year to their health provider, one who has special training in adolescent medicine, they're going to stay healthy."