Rate and Predictors of Repeat Chlamydia trachomatis Infection Among Men

Alarming incidence of reinfections after treatment for Chlamydia trachomatis and gonorrhoea: Can we predict and prevent them?

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections are a public health problem, worsened by frequent reinfections, whose incidence rate is not known in Spain. The objective of this study is to estimate in patients diagnosed with NG, CT or mixed infection (NG and CT): (1) the incidence of reinfections by the same microorganism, (2) the total incidence of Sexually Transmitted Infections (STI), both by the same microorganism and by infections other than the initial one, and (3) to identify predictors of reinfection.

METHODS

Observational prospective case series involving 986 patients with CT and/or NG at specialized STI clinics in Biscay (Spain) between 2016 and 2019.

RESULTS

The six month cumulative incidence of reinfection by the same microorganism was 17.24% (CI95%: 14.9-19.7) and 24.65% (CI95%: 21.9-27.4) for any STI (reinfection or other). Being an immigrant (OR=1.8; CI95%: 1.3-2.6), men who have sex with men (OR=1.8; CI95%: 1.3-2.6), number of sexual partners (OR=4.3; CI95%: 2.7-6.8 for more than 5 partners), having a new partner (OR=1.7; CI95%: 1.08-2.6), not always using a condom (OR=1.4; CI95%: 1.02-1.9) and consumption of alcohol prior to sex (OR=3.8; CI95%: 1.5-9.5) were associated with reinfection by any STI.

CONCLUSION

These characteristics allow doctors to identify patients in whom to prioritize short-term rescreening for repeated infections with any STIs after initial treatment for NG or CT.

Determinants and prediction of Chlamydia trachomatis re-testing and re-infection within 1 year among heterosexuals with chlamydia attending a sexual health clinic

Background

Chlamydia trachomatis (chlamydia) is one of the most common sexually transmitted infections (STI) globally, and re-infections are common. Current Australian guidelines recommend re-testing for chlamydia 3 months after treatment to identify possible re-infection. Patient-delivered partner therapy (PDPT) has been proposed to control chlamydia re-infection among heterosexuals. We aimed to identify determinants and the prediction of chlamydia re-testing and re-infection within 1 year among heterosexuals with chlamydia to identify potential PDPT candidates.

Methods

Our baseline data included 5,806 heterosexuals with chlamydia aged ≥18 years and 2,070 re-tested for chlamydia within 1 year of their chlamydia diagnosis at the Melbourne Sexual Health Center from January 2, 2015, to May 15, 2020. We used routinely collected electronic health record (EHR) variables and machine-learning models to predict chlamydia re-testing and re-infection events. We also used logistic regression to investigate factors associated with chlamydia re-testing and re-infection.

Results

About 2,070 (36%) of 5,806 heterosexuals with chlamydia were re-tested for chlamydia within 1 year. Among those retested, 307 (15%) were re-infected. Multivariable logistic regression analysis showed that older age (≥35 years old), female, living with HIV, being a current sex worker, patient-delivered partner therapy users, and higher numbers of sex partners were associated with an increased chlamydia re-testing within 1 year. Multivariable logistic regression analysis also showed that younger age (18-24 years), male gender, and living with HIV were associated with an increased chlamydia re-infection within 1 year. The XGBoost model was the best model for predicting chlamydia re-testing and re-infection within 1 year among heterosexuals with chlamydia; however, machine learning approaches and these self-reported answers from clients did not provide a good predictive value (AUC < 60.0%).

Conclusion

The low rate of chlamydia re-testing and high rate of chlamydia re-infection among heterosexuals with chlamydia highlights the need for further interventions. Better targeting of individuals more likely to be re-infected is needed to optimize the provision of PDPT and encourage the test of re-infection at 3 months.

Sexually Transmitted Infections Treatment Guidelines, 2021

These guidelines for the treatment of persons who have or are at risk for sexually transmitted infections (STIs) were updated by CDC after consultation with professionals knowledgeable in the field of STIs who met in Atlanta, Georgia, June 11-14, 2019. The information in this report updates the 2015 guidelines. These guidelines discuss 1) updated recommendations for treatment of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis; 2) addition of metronidazole to the recommended treatment regimen for pelvic inflammatory disease; 3) alternative treatment options for bacterial vaginosis; 4) management of Mycoplasma genitalium; 5) human papillomavirus vaccine recommendations and counseling messages; 6) expanded risk factors for syphilis testing among pregnant women; 7) one-time testing for hepatitis C infection; 8) evaluation of men who have sex with men after sexual assault; and 9) two-step testing for serologic diagnosis of genital herpes simplex virus. Physicians and other health care providers can use these guidelines to assist in prevention and treatment of STIs.

Systematic Development of an Intervention to Promote Self-Sampling for HIV and Sexually Transmitted Infections for Men Who Have Sex With Men: An Intervention Mapping Approach

Sexual healthcare aims to reduce HIV and sexually transmitted infections (STIs) by promoting testing and prevention. To better reach men who have sex with men (MSM), additional strategies are needed. Here, we describe development of an intervention, which is part of a broader HIV/STI home-care program, targeted to reach MSM and motivate them to use self-sampling tests. Self-sampling includes blood sampling (finger prick) for HIV, hepatitis B, and syphilis, and a urine sample and oral and anorectal swab samples for chlamydia and gonorrhea. Intervention mapping, a systematic six-step approach, was used to guide the development process: (1) needs assessment including interviews with MSM, (2) create a matrix of change, (3) selection of theory-based methods and practical strategies, (4) intervention development, (5) implementation plan, and (6) evaluation (not included in this paper). Stakeholders were involved to increase program support and feasibility. The needs assessment revealed that testing barriers among MSM related to stigma, time, and privacy concerns. Barriers among healthcare providers related to time, competing priorities, lack of expertise, and guideline restrictions. Included intervention components are designed to overcome these barriers, e.g., engaging role models, with a website with a role model story, and providing tailored information. Methods to reach MSM were a variety of information channels (posters, flyers, and audio-visual displays) and delivery modes, such as advertisements on websites and invitational cards (online and paper) distributed by healthcare providers and MSM themselves (social network testing/peer testing). Our intervention aims to encourage MSM to engage in testing, re-testing, and providing a test to peer MSM. Evidence-based methods to overcome barriers were included to reach and motivate an increased number of MSM. Using intervention mapping stimulated systematic evidence-based decision making and adapting the intervention to the target audience and setting. The next step (step 6) is to implement and evaluate the intervention.

High prevalence and incidence of rectal Chlamydia infection among men who have sex with men in Japan

Background

Rectal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections have been neglected and epidemiological data are unavailable in Japan. Thus, we evaluated the prevalence and incidence of rectal CT/NG in a cohort of HIV-negative men who have sex with men (MSM), which was established at the National Center for Global Health and Medicine (NCGM), in Tokyo, Japan, in January 2017.

Methods

HIV-negative MSM aged ≥16 years old were included. The prevalence of rectal CT/NG among HIV-negative MSM was compared with that among an existing HIV-positive MSM cohort at NCGM. The HIV-negative MSM cohort was examined for rectal and pharyngeal CT/NG every 3 months. Urethral CT/NG was evaluated at the physician’s discretion. The incidences of CT/NG were evaluated in December 2018.

Results

Of 502 MSM initially included in this study, 13 men were diagnosed with HIV infection at enrollment and were subsequently excluded from the analysis. We evaluated 561 HIV-positive MSM for rectal CT/NG. The mean ages of the two cohorts were 33.6 and 46.2 years old, respectively (p<0.001). The prevalences of rectal CT were 16.4% and 15.9% (p = 0.707) and the prevalences of rectal NG were 4.1% and 2.3% (p = 0.101), for the HIV-negative and HIV-positive MSM cohorts, respectively. Of 489 HIV-negative MSM, 328 were followed at least twice, with 261.1 person-years during the study period. The incidences of rectal CT/NG were 17.2 and 3.8/100 person-years and the incidences of pharyngeal CT/NG were 2.0 and 11.0/100 person-years for the two cohorts, respectively. Approximately 37.9% of incident cases were attributed to recurrent infection.

Conclusions

The prevalence and incidence of rectal CT/NG were high among MSM in Tokyo, Japan, suggesting that urgent countermeasures for early diagnosis and treatment are necessary.

Temporal Patterns in Chlamydia Repeat Testing in Massachusetts

INTRODUCTION

National guidelines recommend test-of-cure for pregnant women and test-of-reinfection for all patients with chlamydia infections in order to interrupt transmission and prevent adverse sequelae for patients, partners, and newborns. Little is known about retesting and positivity rates, and whether they are changing over time, particularly in private sector practices.

METHODS

Electronic health record data on patients with chlamydia tests were extracted from three independent clinical practice groups serving ≅20% of the Massachusetts population. Records were extracted using the Electronic medical record Support for Public Health platform (esphealth.org). These data were analyzed for temporal trends in annual repeat testing rates by using generalized estimating equations after index positive chlamydia tests between 2010 and 2015 and for differences in intervals to first repeat tests among pregnant females, non-pregnant females, and males. Data extraction and analysis were performed during calendar years 2017 and 2018.

RESULTS

An index positive C. trachomatis result was identified for 972 pregnant female cases, 10,309 non-pregnant female cases, and 4,973 male cases. Test-of-cure 3-5 weeks after an index positive test occurred in 37% of pregnant females. Test-of-reinfection 8-16 weeks after an index positive test occurred in 39% of pregnant females, 18% of non-pregnant females, and 9% of males. There were no significant increases in test-of-cure or test-of-reinfection rates from 2010 to 2015. Among cases with repeat tests, 16% of pregnant females, 15% of non-pregnant females, and 16% of males had positive results.

CONCLUSIONS

Chlamydia test-of-cure and test-of-reinfection rates are low, with no evidence of improvement over time. There are substantial opportunities to improve adherence to chlamydia repeat testing recommendations.

Not again! Effect of previous test results, age group and reason for testing on (re-)infection with Chlamydia trachomatis in Germany

Background

Infection with Chlamydia trachomatis (Ct) is the most commonly reported sexually transmitted infection in Europe. In Germany, Ct screening is offered free of charge to pregnant women since 1995 and to women < 25 years of age since 2008. For symptomatic individuals, testing is covered by statutory health insurance. Study results have shown that repeat Ct infection occurs in 10–20% of previously infected women and men. Our aim was to describe persons tested for Ct and to investigate the determinants of (repeat) Ct infection in women and men in Germany.

Methods

We analysed Ct test results from men and women tested between 2008 and 2014 in laboratories participating in the German Chlamydia trachomatis Laboratory Sentinel surveillance. Reinfection was defined as at least 2 positive laboratory tests within more than 30 days. We performed logistic regression stratified by sex and, for women, reason for testing to determine the effect of previous test results and age group on subsequent test results.

Results

In total, 2,574,635 Ct tests could be attributed to 1,815,494 women and 123,033 men. 5% of women and 14% of men tested positive at least once. 15–19- and 20–24-year-old women tested positive at least once respectively in 6.8 and 6.0%, while men respectively in 16.6 and 21.2%. Altogether, 23.1% of tested women and 11.9% of tested men were tested repeatedly between 2008 and 2014. Among those who previously tested positive, reinfection occurred in 2.0% of women and 6.6% of men. Likelihood to be tested Ct positive was higher in women and men with a positive Ct test in the past compared to previously tested Ct negative, odds ratios 4.7 and 2.6 (p < 0.01) respectively. Odds ratios ranged by age group and test reason.

Conclusion

A history of Ct infection increased the likelihood of infection with Ct in women and men taking into account the result of the previous test. Health education, safer sex and treatment of partners are necessary for women and men who have tested positive to prevent reinfection and complications and to interrupt the chain of transmission. To identify potential reinfection repeat testing after treatment should be performed.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3323-2) contains supplementary material, which is available to authorized users.

Diagnostic value of detection of serum β-HCG and CT-IgG combined with transvaginal ultrasonography in early tubal pregnancy

The diagnostic value of detection of serum β-human chorionic gonadotropin (β-HCG) and Chlamydia trachomatis immunoglobulin G (CT-IgG) combined with transvaginal ultrasonography in early tubal pregnancy was investigated. A total of 55 patients with early tubal pregnancy were selected as the tubal pregnancy group, while 55 subjects of normal intrauterine pregnancy were enrolled as the intrauterine pregnancy group. Transvaginal ultrasonography and quantitative detection of serum β-HCG and CT-IgG were performed for all patients, and the clinical examination results were analyzed and compared. The endometrial thickness and serum β-HCG level of patients with early tubal pregnancy were significantly lower than those of women with intrauterine pregnancy (6.7±1.5 vs. 11.6±1.2 mm; 776±109 vs. 5,598±187 U/l), and the differences were statistically significant (p<0.01); the serum CT-IgG antibody positive rate of patients in tubal pregnancy group (49.1%) was significantly higher than that in intrauterine pregnancy group (12.7%) (p<0.01); the serum CT-IgG antibody positive rates of patients with degree I, II and III of pelvic adhesion intubal pregnancy group were 28.6, 75.0 and 81.8%, respectively; the more severe the pelvic adhesion was, the higher the CT-IgG positive rate would be. The diagnostic coincidence rate of combined detection was significantly higher than that of single detection of serum β-HCG, progesterone and endometrial thickness. The detection of serum β-HCG and CT-IgG combined with transvaginal ultrasonography can diagnose the early tubal pregnancy soonest possible, and help choose the appropriate therapeutic methods depending on the situation to reduce the tubal damage of patients, so as to provide a reliable basis for the diagnosis, treatment and prognosis, and it has important clinical application value.

Striking ethnic variations in the epidemiology of Chlamydia trachomatis in Haifa District, Israel, throughout the years 2001-2015

Our objectives were to examine trends in the incidence of chlamydia over an extended period and compare the epidemiology of the infection between two distinct ethnic groups in Israel: Jews and Arabs. We examined the incidence rate of Chlamydia trachomatis infection among residents of Haifa District, northern Israel from 2001 to 2015, by reviewing archives of the Department of Epidemiology, Ministry of Health. Notified cases were stratified by age group, gender, and ethnic group. The overall incidence rate of Chlamydia was 10.8 cases per 100,000 population per year. The annual rate increased dramatically from 5.1 per 100,000 population in 2001, to an all-time high of 18.5 cases per 100,000 population in 2015 (P < 0.001), representing an increase of 362.7%. The most affected age group was 25-34 years of age. The estimated rate among Jewish inhabitants was ninefold higher than among Arabs. Only 3% recurrent episodes of Chlamydia were registered. The prevalence of HIV positivity among Chlamydia-infected patients was similar to that of the general population. In conclusion, Chlamydia in Haifa has been continuously increasing since 2001 and the infection is much more prevalent among patients of Jewish ethnicity, mainly due to more hazardous sexual practices in this population.

Self-collected glans/meatal 'dry' swab specimen and NAAT technology detects Chlamydia trachomatis and Neisseria gonorrhoeae - implications for public policy changes

Increasing Chlamydia trachomatis (CT) rates and ever-present Neisseria gonorrhoeae (NG) infections in women have given rise in the past to consideration of male screening programs in order to address the silent male reservoir. Non-medical venues (e.g. home collection, restrooms or other private locations) may be viable venues to reach certain populations that in the past have not been accessed. Effortlessly collected, non-invasive, self-collected male specimens that are stable and easy to transport would enhance the success of male screening programs. We designed a head-to-head study to consider the effectiveness of non-invasive self-collected glans/meatal dry swab (SCS) specimens to detect CT and NG nucleic acid when compared to traditional clinician-collected swab (CCS) specimens and first-catch urine (FCU) specimens. A total of 284 male patients were included in the study. Specimens were processed using the Becton Dickinson ProbeTec ET system. The overall sensitivity of SCS was 91.1% with a specificity of 99.2%. There was an overall SCS agreement of 97.7% with CCS specimens and 90.4% with FCU specimens. Dry swab specimens are easy to collect, transport and test. Non-invasive dry self-collected glans/meatal swab specimens are a viable specimen choice.

Chlamydia trachomatis re-infection in Spain: A STI clinic-based cohort study

BACKGROUND

Chlamydia trachomatis (C. trachomatis) is the most frequently reported sexually transmitted infection (STI) in developed countries, but there is a lack data on its incidence and population dynamics in Spain. The objectives of this study were to estimate the incidence of C. trachomatis in patients seeking medical attention in an STI clinic with a defined population catchment area, to identify factors associated with this infection, and to explore differences between factors associated with new infections and re-infections.

METHODS

A retrospective study was conducted on a cohort of patients from a STI clinic who underwent chlamydia testing at least twice between 2007 and 2015.

RESULTS

Of the 2633 patients who met study selection criteria, 795 (30.2%) tested positive for C. trachomatis at baseline (baseline Chlamydia). The overall incidence was 7.97/100 person-years (95% CI: 7.2-8.8): 5.9/100 person-years (95% CI: 5.2-6.7) among patients testing negative for C. trachomatis at baseline, and 18.3 person-years (95% CI: 15.6-21.5) among those testing positive at baseline. In multivariate analysis, the factors independently associated with overall incidence were a history of infection with C. trachomatis in the previous 6 months (hazard ratio=3.6; 95% CI: 2.3-5.4), younger age (HR <20 vs ≥35 years=5.5; 95% CI: 3.2-9.5), male sex, 2 or more sexual partners in the previous month and year, and inconsistent condom use.

CONCLUSIONS

Guidelines should be established for C. trachomatis in Spain, including recommendations on the need for follow-up and re-testing, independently of age. Though data concerning the optimal timing of re-testing are inconclusive, our findings support the establishment of a 3-6 month interval.

Chlamydia trachomatis Genital Tract Infections: When Host Immune Response and the Microbiome Collide

Genital infections with Chlamydia trachomatis continue to be a major health problem worldwide. While some individuals clear their infection (presumed to be the result of an effective Th1/interferon-γ response), others develop chronic infections and some are prone to repeat infections. In females in particular, chronic asymptomatic infections are common and can lead to pelvic inflammatory disease and infertility. Recent studies suggest that the genital tract microbiota could be a significant factor and explain person-to-person variation in C. trachomatis infections. One hypothesis suggests that C. trachomatis can use its trpBA genes to rescue tryptophan from indole, which is a product of anaerobic members of the genital tract microbiota. Women with particular microbiota types, such as seen in bacterial vaginosis, have increased numbers of anaerobes, and this would enable the chlamydia in these individuals to overcome the host's interferon-γ attempts to eliminate it, resulting in more repeat and/or chronic infections.

Sexual abstinence and other behaviours immediately following a new STI diagnosis among STI clinic patients: Findings from the Safe in the City trial

BACKGROUND

Few studies have assessed patients' sexual behaviours during the period immediately following a new diagnosis of a curable sexually transmitted infection (STI).

METHODS

Data were analysed from a behavioural study nested within the Safe in the City trial, which evaluated a video-based STI/HIV prevention intervention in three urban STI clinics. We studied 450 patients who reported having received a new STI diagnosis, or STI treatment, 3 months earlier. Participants reported on whether they seriously considered, attempted and succeeded in adopting seven sex-related behaviours in the interval following the diagnostic visit. We used multivariable logistic regression to identify, among men, correlates of two behaviours related to immediately reducing reinfection risk and preventing further STI transmission: sexual abstinence until participants were adequately treated and abstinence until their partners were tested for STIs.

RESULTS

Most participants reported successfully abstaining from sex until they were adequately treated for their baseline infection (89%-90%) and from sex with potentially exposed partners until their partners were tested for HIV and other STIs (66%-70%). Among men who intended to be abstinent until they were adequately treated, those who did not discuss the risks with a partner who was possibly exposed were more likely not to be abstinent (OR, 3.7; 95% CI 1.5 to 9.0) than those who had this discussion. Similarly, among men who intended to abstain from sex with any potentially exposed partner until the partner was tested for HIV and other STIs, those who reported not discussing the risks of infecting each other with HIV/STIs were more likely to be sexually active during this period (OR, 3.5; 95% CI 1.6 to 8.1) than were those who reported this communication.

CONCLUSIONS

Improved partner communication could facilitate an important role in the adoption of protective behaviours in the interval immediately after receiving a new STI diagnosis.

TRIAL REGISTRATION NUMBER

NCT00137670.

Background review for the '2015 European guideline on the management of Chlamydia trachomatis infections'

SummaryChlamydia trachomatis infections are major public health concerns globally. Of particular grave concern is that the majority of persons with anogenital Chlamydia trachomatis infections are asymptomatic and accordingly not aware of their infection, and this silent infection can subsequently result in severe reproductive tract complications and sequelae. The current review paper provides all background, evidence base and discussions for the 2015 European guideline on the management of Chlamydia trachomatis infections (Lanjouw E, et al. Int J STD AIDS 2015). Comprehensive information and recommendations are included regarding the diagnosis, treatment and prevention of anogenital, pharyngeal and conjunctival Chlamydia trachomatis infections in European countries. However, Chlamydia trachomatis also causes the eye infection trachoma, which is not a sexually transmitted infection. The 2015 European Chlamydia trachomatis guideline provides up-to-date guidance regarding broader indications for testing and treatment of Chlamydia trachomatis infections; clearer recommendation of using validated nucleic acid amplification tests only for diagnosis; advice on (repeated) Chlamydia trachomatis testing; recommendation of increased testing to reduce the incidence of pelvic inflammatory disease and prevent exposure to infection and recommendations to identify, verify and report Chlamydia trachomatis variants. Improvement of access to testing, test performance, diagnostics, antimicrobial treatment and follow-up of Chlamydia trachomatis patients are crucial to control its spread.

Investigating the epidemiology of repeat Chlamydia trachomatis detection after treatment by using C. trachomatis OmpA genotyping

Repeat Chlamydia trachomatis detection frequently occurs within months after C. trachomatis infection treatment. The origins of such infection (persistence versus reinfection from untreated or new partners) are varied and difficult to determine. C. trachomatis strains can be differentiated by sequencing the ompA gene encoding the outer membrane protein A (OmpA). We used OmpA genotyping to investigate the epidemiology of repeat C. trachomatis detection after treatment in C. trachomatis-infected subjects seen at a sexually transmitted diseases clinic. Subjects were enrolled, tested for C. trachomatis, treated with azithromycin, and scheduled for a 6-month follow-up for repeat C. trachomatis testing. OmpA genotyping was performed on C. trachomatis-positive urogenital specimens obtained from patients at enrollment and follow-up. The enrollment visit OmpA genotypes for C. trachomatis were determined for 162 subjects (92% female, 94% African American). C. trachomatis was detected at follow-up in 39 subjects (24%). The OmpA genotype distribution at enrollment did not differ in those with versus those without repeat C. trachomatis detection. Of the 35 subjects with C. trachomatis strains genotyped at enrollment and follow-up, 7 (20%) had the same ompA sequence at both visits, while 28 (80%) had discordant sequences. A new sexual partner was reported more often in subjects with discordant C. trachomatis strains than in those with concordant strains (13 [46%] versus 1 [14%]; P = 0.195). Half of the subjects with discordant C. trachomatis strains who reported sexual activity since treatment denied a new sexual partner; 62% of these subjects reported that their partner was treated. Our study demonstrates that most repeat C. trachomatis detections after treatment were new infections with a different C. trachomatis strain rather than reinfection with the same strain. OmpA genotyping can be a useful tool in understanding the origins of repeat C. trachomatis detection after treatment.

Recent advances in understanding and managing Chlamydia trachomatis infections

Worldwide, Chlamydia trachomatis infections rank among the most common sexually transmitted infections (STI), and cause notable reproductive morbidity in women. Although advances in highly accurate and non-invasive diagnostic testing have allowed for better estimation of the burden of disease—especially the asymptomatic state—we still lack a true point-of-care test, and many infections go undetected and untreated. Moreover, limited resources and effort for managing sexual partners of those in whom infection is actually identified comprise a major challenge to control. Here, we review the current state of understanding of this common infection, and efforts to control it.

Chlamydia trachomatis infection rates among a cohort of mobile soldiers stationed at Fort Bragg, North Carolina, 2005-2010

Background

Fort Bragg, a large Army installation with reported high Chlamydia trachomatis (Ct) infection rates, is characterized by a highly mobile population and a surrounding Ct-endemic community. We assessed the rates of Ct incidence and recurrence among the installation’s active component Army personnel and determined the association of soldier transience, sociodemographic factors, and history of sexually transmitted infection (STI) with these rates.

Methods

A cohort of soldiers stationed at Fort Bragg during 2005 to mid-2010 was followed for incident and recurrent Ct infection using laboratory-confirmed reportable disease data. Linkage to demographic and administrative data permitted multivariate analysis to determine association of covariates with initial or recurrent infection.

Results

Among 67,425 soldiers, 2,198 (3.3%) contracted an incident Ct infection (crude incidence, 21.7 per 1,000 person-years). Among soldiers followed for incident infection, 223 (10.6%, crude incidence 110.8 per 1,000 person-years) contracted a recurrent Ct infection. Being female, of lower rank, under 26 years of age, of non-white race, single, or with a high school diploma or less was significantly associated with incident Ct infection. Having breaks in duty or having deployments during follow-up was associated with a lower infection rate. Among women, having prior deployments was associated with a lower rate of both incident and recurrent infection. Specifically associated with recurrent infection in women was age under 21 years or no education beyond high school.

Conclusions

This analysis reaffirms risk factors for Ct infection determined in other studies. In addition, infection risk was lower for more mobile soldiers and tied to the specific location of their regular duty assignment. The findings support the STI prevention efforts at Fort Bragg and the surrounding community, regardless of how often or for how long soldiers have deployed for military operations.

Spontaneous resolution of genital Chlamydia trachomatis infection in women and protection from reinfection

The natural history of chlamydia is variable and may include persisting asymptomatic infection, complications, or spontaneous resolution before treatment. Reinfection is common. We evaluated whether spontaneous resolution was associated with decreased reinfection in women returning for treatment of a positive chlamydia screening test. At enrollment, participants were tested for chlamydia, treated with azithromycin, and scheduled for a 6-month follow-up visit for repeat testing. Two hundred participants returned 1 to 12 months after treatment. Spontaneous resolution at enrollment was demonstrated in 44 (22.0%). Reinfection at follow-up occurred in 33 (16.5%), being more frequent in those with persisting infection at enrollment versus spontaneous resolution (31 of 156 [19.9%] vs 2 of 44 [4.5%]; P = .016). Adjusting for age, the odds of reinfection was 4 times higher for participants with persisting infection at enrollment (odds ratio 4.0, 95% confidence interval, 1.1-25.6; P = .034). Chlamydia treatment may attenuate protective immunity in some patients.

Interventions to prevent sexually transmitted infections, including HIV infection

The Centers for Disease Control and Prevention (CDC) Sexually Transmitted Disease (STD) Treatment Guidelines were last updated in 2006. To update the "Clinical Guide to Prevention Services" section of the 2010 CDC STD Treatment Guidelines, we reviewed the recent science with reference to interventions designed to prevent acquisition of STDs, including human immunodeficiency virus (HIV) infection. Major interval developments include (1) licensure and uptake of immunization against genital human papillomavirus, (2) validation of male circumcision as a potent prevention tool against acquisition of HIV and some other sexually transmitted infections (STIs), (3) failure of a promising HIV vaccine candidate to afford protection against HIV acquisition, (4) encouragement about the use of antiretroviral agents as preexposure prophylaxis to reduce risk of HIV and herpes simplex virus acquisition, (5) enhanced emphasis on expedited partner management and rescreening for persons infected with Chlamydia trachomatis and Neisseria gonorrhoeae, (6) recognition that behavioral interventions will be needed to address a new trend of sexually transmitted hepatitis C among men who have sex with men, and (7) the availability of a modified female condom. A range of preventive interventions is needed to reduce the risks of acquiring STI, including HIV infection, among sexually active people, and a flexible approach targeted to specific populations should integrate combinations of biomedical, behavioral, and structural interventions. These would ideally involve an array of prevention contexts, including (1) communications and practices among sexual partners, (2) transactions between individual clients and their healthcare providers, and (3) comprehensive population-level strategies for prioritizing prevention research, ensuring accurate outcome assessment, and formulating health policy.

Murine Chlamydia trachomatis genital infection is unaltered by depletion of CD4+ T cells and diminished adaptive immunity

Chlamydia muridarum and Chlamydia trachomatis mouse models of genital infection have been used to study chlamydial immunity and vaccine development. To assess the protective role of CD4(+) T cells in resolving C. trachomatis and C. muridarum genital tract infections, we used the female mouse model and evaluated infection in the presence and absence of CD4(+) T cells. In contrast to C. muridarum infection, C. trachomatis infection was unaltered in the absence of CD4(+) T cells. Mice infected with C. trachomatis developed protective immunity to re-challenge, but unlike C. muridarum infection, optimum resistance required multiple infectious challenges, despite the generation of adaptive serum and local chlamydial specific immune responses. Thus, understanding the chlamydial pathogenic and host immunologic factors that result in a diminished protective role for CD4(+) T cells in C. trachomatis murine infection might lead to new insights important to human immunity and vaccine development.