Screening in High Schools May Lower the Prevalence of Sexually Transmitted Diseases
WebMD News Archive
Dec. 23, 1999 (Los Angeles) -- The best way to detect sexually transmitted
diseases (STDs) in adolescents is universal screening, according to a study in
the December issue of the journal Pediatrics.
"Just as routine eye exams and other tests are offered in high school,
perhaps we should be routinely testing for STDs," says lead researcher
Thomas A. Farley, MD.
Common STDs include chlamydia, gonorrhea, herpes, and syphilis. It's
estimated that 3 million teenagers are infected annually. Many of the diseases
are treatable if they are diagnosed early, but if left untreated they can put
the teens at risk for further health problems. In women, chlamydia can lead to
pelvic inflammatory disease, a painful disorder and one of the major causes of
infertility in the U.S. Gonorrhea can make it easier to contract HIV, the virus
that causes AIDS.
Testing in this age group is particularly important because young people
often have no symptoms, so they will not come for tests or treatment on their
own, Farley tells WebMD. Also, many adolescents are embarrassed to admit they
are sexually active. Routine testing without requiring students to confess to
sexual activity can circumvent this shyness, he says.
For three consecutive school years, Farley, who is medical director of
STD/HIV Programs in the Louisiana Office of Public Health, and his colleagues
offered tests for chlamydia and gonorrhea to all students in grades 9-12 at
three high schools serving approximately 2,000 students. For comparison, they
looked at five schools with approximately 5,000 students in which screening was
not offered until the third year, allowing the researchers to evaluate the
effects of repeated screening. Parental consent was required for students to
have the test.
During the three years of the study, more than half of the 9th- through
12th-graders in the three test schools participated. Of the total enrolled
population available for at least two of the three years, 83% were tested at
least once. In the five schools offering testing only in the final year, 52% of
the eligible students were tested.
For all three years of testing and in all eight schools combined, the
prevalence of chlamydia was 6% for boys and 11.5% for girls. The prevalence
increased with age and nearly doubled between grades 9 and 12. There was less
of an age difference with gonorrhea, but again prevalence tended to be twice as
high in girls as in boys.
More than 90% of the students found to be infected on the first test had no
symptoms. Infected students were treated with antibiotics and given
The researchers were encouraged by some of their findings. With repeated
testing, chlamydia prevalence among boys dropped to 3%, compared to the 6%
prevalence seen in the comparison schools. Among girls, although less
impressive, the chlamydia prevalence declined to 10% from 12% in the comparison
Gonorrhea prevalence declined in girls, from 3% in the first year to 2% in
the third year. These declines, especially in chlamydia prevalence among boys,
indicate that STD screening programs in high schools have the potential to
reduce infections in adolescents.
STDs "can cause serious long-term complications," Farley warns.
Since these diseases often cause no symptoms in their early stages, he
recommends that consumers, especially teenagers, request screening from their
doctors. "If we want to control gonorrhea and chlamydia, we must do more
widespread testing in the clinic, as well as in schools."