Expedited partner therapy (EPT), the practice of treating the sex partners of persons with sexually transmitted infections without their medical evaluation, increases partner treatment and decreases gonorrhea and chlamydia reinfection rates. We conducted a stepped-wedge, community-level randomized trial to determine whether a public health intervention promoting EPT could increase its use and decrease chlamydia test positivity and gonorrhea incidence in women.
Methods and Findings
The trial randomly assigned local health jurisdictions (LHJs) in Washington State, US, into four study waves. Waves instituted the intervention in randomly assigned order at intervals of 6–8 mo. Of the state’s 25 LHJs, 24 were eligible and 23 participated. Heterosexual individuals with gonorrhea or chlamydial infection were eligible for the intervention. The study made free patient-delivered partner therapy (PDPT) available to clinicians, and provided public health partner services based on clinician referral. The main study outcomes were chlamydia test positivity among women ages 14–25 y in 219 sentinel clinics, and incidence of reported gonorrhea in women, both measured at the community level. Receipt of PDPT from clinicians was evaluated among randomly selected patients. 23 and 22 LHJs provided data on gonorrhea and chlamydia outcomes, respectively. The intervention increased the percentage of persons receiving PDPT from clinicians (from 18% to 34%, p < 0.001) and the percentage receiving partner services (from 25% to 45%, p < 0.001). Chlamydia test positivity and gonorrhea incidence in women decreased over the study period, from 8.2% to 6.5% and from 59.6 to 26.4 per 100,000, respectively. After adjusting for temporal trends, the intervention was associated with an approximately 10% reduction in both chlamydia positivity and gonorrhea incidence, though the confidence bounds on these outcomes both crossed one (chlamydia positivity prevalence ratio = 0.89, 95% CI 0.77–1.04, p = 0.15; gonorrhea incidence rate ratio = 0.91, 95% CI .71–1.16, p = 0.45). Study findings were potentially limited by inadequate statistical power, by the institution of some aspects of the study intervention outside of the research randomization sequence, and by the fact that LHJs did not constitute truly isolated sexual networks.
A public health intervention promoting the use of free PDPT substantially increased its use and may have resulted in decreased chlamydial and gonococcal infections at the population level.
Every day, more than 1 million people worldwide acquire a sexually transmitted infection (STI). STIs are viral, bacterial, or parasitic infections that pass between people during sexual activity (through semen, vaginal fluids, blood, or skin-to-skin contact). Two of the most common STIs—chlamydia and gonorrhea—are caused by bacteria (Chlamydia trachomatis and Neisseria gonorrhoeae, respectively). Chlamydia rarely has any symptoms, especially in women, although some infected individuals experience pain when urinating or a discharge from the penis or vagina. The typical symptoms of gonorrhea (“the clap”) include a thick green or yellow discharge from the vagina or penis and pain when urinating, but about 10% of infected men and half of infected women have no symptoms. Both these STIs are diagnosed by testing a urine sample or a genital swab and can be treated with antibiotics. If left untreated, both infections can spread to other parts of the body and cause serious health problems including pelvic inflammatory disease (infection of the internal reproductive organs) and infertility in women.
Why Was This Study Done?
Condom use during sex reduces the risk of getting or passing on chlamydia or gonorrhea, but additional approaches are needed to reduce the incidence (the number of new cases in a population in a year) of these STIs. One promising approach is expedited partner therapy (EPT)—treating the sex partners of people with a curable STI without requiring the partners to undergo a medical evaluation. EPT usually involves clinicians giving their patients antibiotics to give to their sex partners (patient-delivered partner therapy, or PDPT). Although clinical trials of EPT have shown that the approach increases partner treatment and decreases gonorrhea and chlamydia reinfection rates, EPT has not been widely adopted in the US. In this stepped-wedge, community-level randomized trial, the researchers test whether a public health program can increase the population-level use of EPT and decrease the prevalence of chlamydial infection (the proportion of a population that has chlamydia) and the incidence of gonorrhea in women. A stepped-wedge randomized trial sequentially and randomly rolls out an intervention to groups (clusters) of people and compares outcomes both between groups and within groups before and after the intervention.
What Did the Researchers Do and Find?
The researchers randomly assigned local health jurisdictions in Washington State, US, to one of four study groups. The intervention, which was instituted sequentially by the groups at intervals of 6–8 months, included the provision of free PDPT packs for clinicians to hand to their patients and the provision of partner services—public health department staff offered patients free PDPT to treat up to three partners and offered to contact the partners of patients who did not want to notify their partners personally about their STI. During the 22-month trial, the intervention increased the proportion of patients receiving PDPT from clinicians from 18% to 34% and the proportion of patients receiving partner services from 25% to 45%. Chlamydia test positivity among young women attending clinics established to screen for chlamydia and gonorrhea as part of US infertility prevention efforts (sentinel clinics) decreased from 8.2% to 6.5%. The incidence of reported gonorrhea among women in the state (gonorrhea infrequently infects women in Washington State, so the researchers needed to look at a larger population than women attending sentinel clinics to get reliable figures for their analysis) decreased from 59.6 per 100,000 to 26.4 per 100,000. After adjusting for temporal trends (changes in the incidence of STIs over time unrelated to the intervention) and running appropriate statistical models, the researchers estimated that the intervention was associated with an approximately 10% reduction in chlamydia positivity and gonorrhea incidence, although these results were statistically insignificant and may therefore be chance findings.
What Do These Findings Mean?
Some aspects of this trial may limit the accuracy and robustness of its findings. For example, during the study period, there was an increase in partner services outside the trial that might have contributed to the observed decreases in STIs and decreased the study’s ability to find an effect associated with the study intervention. Nevertheless, these findings show that the implementation of a public health program promoting the provision of free PDPT substantially increased PDPT use by clinicians in Washington State. Moreover, although the trial did not definitively show that EPT decreased chlamydia test positivity or the incidence of gonorrhea, substantial population-level declines in both STIs occurred concurrently with the introduction of the intervention. The researchers conclude that the continued use and expansion of EPT as a way to reduce the incidence of chlamydia and gonorrhea is warranted, and suggest that the public health intervention used in this trial provides a model for health departments seeking to increase EPT use.
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001777.
The World Health Organization provides a fact sheet about sexually transmitted infections (in several languages)
The US Centers for Disease Control and Prevention provides detailed information about sexually transmitted diseases, chlamydia, gonorrhea, and expedited partner therapy (some information available in several languages)
The UK National Health Service Choices website provides information about chlamydia (including some personal stories) and gonorrhea
Healthtalkonline (a not-for-profit organization) provides personal stories about sexually transmitted infections
MedlinePlus provides links to further resources about sexually transmitted infections (in English and Spanish)
More information about this trial is available
The Washington State Department of Health website includes information about Washington State’s EPT program, including EPT guidelines and information related to the legal process for instituting EPT in the state
Matthew Golden and colleagues report on the effects of promoting treatment without testing for sexual partners of patients with chlamydia or gonorrhea.