Rates of chlamydia trachomatis infection, the most common sexually transmitted infection (STI) in the United States, are on the rise. The CDC recently announced that the prevalence of this infection reached an unprecedented high in 2015, increasing by nearly 6% over 2014, with more than 1.5 million cases reported. Compounding the problem is the growing realization that current screening approaches leave out too many individuals who should be screened. This inadequate coverage highlights the likelihood for an even higher prevalence of the infection and the urgency for better screening approaches.
According to a CDC survey conducted during 2007-2012, chlamydia infection rates were 2.9% among women aged 20 to 24 and 2.4% in women aged 14 to 19. Chlamydia prevalence rates in women aged 25 to 39 were half those of younger women (1.1%). The recent surge in prevalence has occurred in young people aged 15-24.
Current guidelines issued by the CDC, the United States Preventative Services Task Force, and the American Academy of Pediatrics recommend that all sexually active women younger than age 25 and at-risk women older than age 25 be screened annually for chlamydia. Despite these recommendations, only 38% of sexually active women aged 15 to 25 who should be tested actually receive testing for chlamydia. Moreover, screening rates are lowest among those aged 15 to 19, the age group with the highest chlamydia prevalence. These data suggest that screening decisions may be based more on risk factors rather than guidelines. It’s also possible that many women choose not to “opt in” for the testing. The difficulty in identifying women at risk—including both physician recognized and patient identified—constitutes a major barrier to improved coverage.
Addressing the Issue
Universal screening for chlamydia is a proposed approach that focuses on using these screens as part of a routine component of physical exams rather than basing testing on sexual activity. All young women—regardless of their reported sexual activity—are eligible for these tests and should receive them unless they elect to “opt out.”
In a recent study, the potential health benefits and cost effectiveness of universal chlamydia screening were compared with those of risk-based screening. The study model assumed an 80% insurance coverage rate, an 83% healthcare utilization rate, and a 75% test acceptance rate. Costs and benefits were tracked over 50 years. The model predicted that overall chlamydia prevalence would be cut by 55% in women by replacing risk-based screening with universal screening. Additionally, a 20% reduction in total costs—including direct medical costs for testing and treatment and indirect costs for lost productivity—was predicted by the model.
Failing to identify and treat chlamydia infections can lead to cervicitis, which can progress to pelvic inflammatory disease and other potentially more serious conditions, such as ectopic pregnancy or infertility. In addition, a recent meta-analysis showed that women with chlamydia have a two-fold higher risk for developing cervical cancer. In light of these data, universal screening has great potential to provide significant personal health benefits.
Public health may also benefit from lower chlamydia infection rates and reductions in medical costs associated with infection and disease progression in the absence of treatment. Universal screening also provides an opportunity for physicians to initiate a productive dialog with patients concerning sexual health and risks for other STIs that could further improve health outcomes.
Readings & Resources (click to view)
Torrone E, Papp J, Weinstock H, et al. Prevalence of Chlamydia trachomatis genital infection among persons aged 14-39 years ̶ United States, 2007-2012. MMWR Morb Mortal Wkly Rep. 2014;63:834-838.
Committee on Adolescence and Society for Adolescent Health and Medicine. Screening for nonviral sexually transmitted infections in adolescents and young adults. Pediatrics. 2014;134:e302-e311.
Meyers D, Wolff T, Gregory K, et al. USPSTF recommendations for STI screening. Available at
Owusu-Edusei K, Hoover K, Gift T. Cost-effectiveness of opt-out chlamydia testing for high-risk young women in the U.S. Am J Prev Med. 2016;51:216-224.
Burstein G, Snyder M, Conley D, et al. Chlamydia screening in a health plan before and after a national performance measure introduction. Obstet Gynecol. 2005;106:327-334.
Hoover K, Tao G. Missed opportunities for chlamydia screening of young women in the United States. Obstet Gynecol. 2008;111:1097-1102.
Hoover K, Tao G, Kent C. Low rates of both asymptomatic chlamydia screening and diagnostic testing of women in US outpatient clinics. Obstet Gynecol. 2008;112:891-898.
DiClemente R, Sales J, Danner F, Crosby R. Abstinence. Pediatrics. 2011;127:208-213.
Zhu H, Shen Z, Luo H, et al. Chlamydia trachomatis infection-associated risk of cervical cancer: a meta-analysis. Medicine 2016;95:e3077.