It's not what you know, but who you know: Risk factors for re-infection in the Philadelphia High School STD Screening Program

Since Fall 2003, the Philadelphia High School STD Screening Program (PHSSSP) has actively sought to retest students who tested positive for CT and/or GC and were previously treated within the PHSSSP, following CDC guidelines to retest approximately 3 months after initial treatment for CT. We sought to determine risk factors associated with CT and GC reinfection within the same school year among students screened by the PHSSSP in order to identify ways in which re-infection can be reduced. We conducted a retrospective cohort analysis of high school students who screened positive for CT and/or GC at least once between Fall 2003 and Spring 2006, and who had treatment and were retested later in the same school year. We created logistic regression models to evaluate associations between the risk of reinfection and gender, race, age, time-to-retest, home ZIP code morbidity, and status of treatment for partners named. Crude reinfection rates among the 583 students retested were 14.7%, 11.2%, and 12.6% in 3 consecutive school years from 2003-2006. Overall, female students who named partners who PHSSSP were unable to locate and treat were at the highest risk of reinfection [27% reinfection] yielding an adjusted odds ratio of 3.02 [Reference group: all other females, P<0.01]. Results also indicated students who self-identified as black were at higher risk for retesting positive compared to other race/ethnicity groups. STD programs' efforts to find and treat partners of infected high school students may be very important in reducing reinfection.