Background:
In the 2002-2003 school year, the Sexually Transmitted Disease (STD) Control Program of the Philadelphia Department of Public Health initiated the Philadelphia High School STD Screening Program (PHSSSP), which offers annual, voluntary, urine-based Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) screening at every public high school.

Objective:
Describe factors associated with STD prevalence in the PHSSSP over 5 years.

Method:
All valid screening tests submitted for the PHSSSP from the 2002-2007 school years were included in this analysis. Analyses were conducted to describe the relationship between positivity and several descriptive factors including sex, age group, school type, and self-reported race/ethnicity. Multivariable analysis was conducted to control for the time between testing offered at each school and its effect on positivity.

Result:
Overall, prevalence for CT and/or GC infections was highest in Year 1 (5.3%), but has remained at about 4.9% since. The number of screening tests declined steadily over the first 4 years, but remained steady for Year 5. There has been little change in male positivity (~2.5%), but positivity in females declined from 8.4% in Year 1 to 7.2% in Year 5. Males show increasing prevalence as age increases, whereas females show a uniform prevalence among 15-19 year olds.

Conclusion:
Screening in the PHSSSP has been successful in detecting and treating adolescents with STD infections and has provided insight into prevalence trends among a large cohort of adolescents. While approximately 25% of the high school population changes each year, prevalence appears to be stabilizing within PHSSSP.

Implications:
After 5 years of annual screening, prevalence has decreased in high schools, but is still high enough to warrant the continuation of PHSSSP. If prevalence remains stable or increases, additional strategies will be considered to address high prevalence in adolescents.