Mary Jett-Goheen

Performance of the Cepheid CT/NG Xpert Rapid PCR Test for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae

ABSTRACT Tests for Chlamydia trachomatis and Neisseria gonorrhoeae, which can provide results rapidly to guide therapeutic decision-making, offer patient care advantages over laboratory-based tests that require several days to provide results. We compared results from the Cepheid GeneXpert CT/NG (Xpert) assay to results from two currently approved nucleic acid amplification assays in 1,722 female and 1,387 male volunteers. Results for chlamydia in females demonstrated sensitivities for endocervical, vaginal, and urine samples of 97.4%, 98.7%, and 97.6%, respectively, and for urine samples from males, a sensitivity of 97.5%, with all specificity estimates being ≥99.4%. Results for gonorrhea in females demonstrated sensitivities for endocervical, vaginal, and urine samples of 100.0%, 100.0%, and 95.6%, respectively, and for urine samples from males, a sensitivity of 98.0%, with all estimates of specificity being ≥99.8%. These results indicate that this short-turnaround-time test can be used to accurately test patients and to possibly do so at the site of care, thus potentially improving chlamydia and gonorrhea control efforts.

Internet-based Screening for Sexually Transmitted Infections To Reach Nonclinic Populations in the Community: Risk Factors for Infection in Men

Background: Internet-based screening for sexually transmitted infections (STIs) has been acceptable to women, and can reach high-risk populations. No prior published data describe internet-based screening for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis in men. We studied whether internet-based screening was acceptable and reached a high-risk population, and what risk factors were associated with STI positivity. Methods: The website, www.iwantthekit.org, encouraged men ≥14 years of age to request a home self-sampling kit and a questionnaire on risk factors and acceptability of internet-based screening. Penile swabs and urine samples were tested for C. trachomatis, N. gonorrhoeae, and T. vaginalis using a nucleic acid amplification test. Risk factors and acceptability were examined using chi squared tests and logistic regression. Results: Of 501 samples received for testing, 106 (21%) were positive for at least one STI, 64 (13%) for chlamydia, 4 (1%) for gonorrhea, and 49 (10%) for trichomonas. In multivariable analyses, age, race, household income, and frequency of condom use were independently associated with infection with at least one STI. Of the total respondents, 34% had a prior STI; 29% reported having a partner with an STI, but only 13% reported always using a condom. Among the men who participated in this study, 77% preferred a self-administered specimen versus attending a clinic, 89% reported that swab use was easy, and 89% reported that they would use internet-based screening again. Conclusions: Men who accessed internet-based screening had known risk factors for STIs and had a high prevalence of infection. Internet-based screening was acceptable and could reach these high-risk men who might not otherwise be reached through traditional means.

Comparative effectiveness of a rapid point-of-care test for detection of Chlamydia trachomatis among women in a clinical setting

Objectives To compare the effectiveness and cost-effectiveness of a promising new point-of-care (POC) chlamydia test with traditional nucleic acid amplification testing (NAAT), and to determine the characteristics that would make a POC test most cost-effective. Methods A decision tree was constructed to model chlamydia screening visits to a sexually transmitted disease clinic by a hypothetical cohort of 10 000 women. The model incorporated programmatic screening costs, treatment costs and medical costs averted through prevention of pelvic inflammatory disease (PID) and its sequelae. Parameter values and costs were estimated for each node in the decision tree based on primary data, published data and unpublished health data. Results For the base-case scenario (POC sensitivity 92.9%; 47.5% of women willing to wait 40 min for test results; test cost

Perceptions of an ideal point-of-care test for sexually transmitted infections - A qualitative study of focus group discussions with medical providers

33.48), POC was estimated to save US

Trichomonas vaginalis infection in women who submit self-obtained vaginal samples after Internet recruitment

5050 for each case of PID averted compared with NAAT. One-way sensitivity analyses indicated that POC would dominate NAAT if the POC test cost is <US

Trichomonas vaginalis infection in men who submit self-collected penile swabs after internet recruitment

41.52 or if POC sensitivity is ≥87.1%. In a probabilistic sensitivity analysis (Monte Carlo simulations, 10 000 iterations), 10.8% of iterations indicated that the POC strategy dominated the NAAT strategy. The mean incremental cost-effectiveness ratio indicated that the POC strategy would save US

Use of tablet-based kiosks in the emergency department to guide patient HIV self-testing with a point-of-care oral fluid test

28 in total, and avert 14 PID cases. Conclusions A promising new chlamydia POC test is likely to be cost-effective compared with traditional NAAT. The POC test sensitivity, cost and proportion of women willing to wait for the POC test result are key elements to determining the cost-effectiveness of any new POC test strategy.

Cost-effectiveness analysis of Chlamydia trachomatis screening via internet-based self-collected swabs compared with clinic-based sample collection.

Background A point-of-care test (POCT) for sexually transmitted infections (STIs), which offers immediate diagnosis resulting in patients receiving diagnosis and treatment in a single visit, has the ability to address some of the STI control needs. However, needs assessment from STI experts and end users about currently available STI POCTs and their future new development has not been evaluated since World Health Organization Sexually Transmitted Diseases Diagnostics Initiative was formed over 15 years ago. Therefore, our objective was to explore the perceptions of the ideal types of STI POCT for use in health care settings. Methodology/Principal Findings A qualitative study, encompassing eight focus groups, was conducted from March 2008 through April 2009. Participants included 6 STD clinic directors, 63 clinicians, and 7 public health/laboratory/epidemiology professionals in the STI field. Discussion topics included currently available POCT, perceived barriers to using POCT in clinics, priority STI for the development of new POCT, and characteristics of the ideal POCT. All discussions were recorded and transcribed verbatim. Themes raised as barriers for current POCT included complexity, long time frames of the so-called “rapid” test, multiple time-driven steps, requiring laboratory technician, difficulty in reading result, interruption of workflow, unreliability, and invasiveness. Chlamydia trachomatis was identified as the priority organism for development of a new STI POCT. Themes indicated for the ideal POCT included rapid turnaround (up to 20 minutes), ease of use, non-invasive, accurate (preferred sensitivity and specificity in the range of high 90s), Clinical Laboratory Improvement Amendments (CLIA)-waived, user-friendly (for both patients and staff), compact, durable, and sturdy. Conclusions/Significance Focus group discussions with STI experts and professionals highlighted chlamydia as the top priority pathogen for POCT development, and identified the qualities of new POCT for STIs. Participants endorsed ease of use, rapid turnaround and high accuracy as essential characteristics of an ideal POCT.

Characteristics and predictors of women who obtain rescreening for sexually transmitted infections using the www.iwantthekit.org screening programme.

Background: Submission of self-obtained vaginal samples (SOVs) collected at home could remove barriers that women face in getting tested for sexually transmitted infections (STIs). Internet recruitment of SOVs is highly acceptable. Methods: Sexually active women ≥14 years were recruited by an educational Internet program, available at: www.iwantthekit.org (IWTK), which offered free testing for trichomonas as part of a panel, which also offered testing for chlamydia and gonorrhea. Kits were ordered online, SOVs were sent through US mail to the laboratory, and tested by nucleic acid amplification tests. Demographics and sexual risk factors were accessed by questionnaires. Women called or were contacted to receive their results. Results: Of women requesting kits, 1525 (43%) returned swabs by mail. In all, 61% were <25 years, 52% were black, and 80% were single. Vaginal discharge was reported by 44%, prevalence for trichomonas was 10% (10% for chlamydia, 1% for gonorrhea), and 18% had at least one prevalent STI. Multivariate logistic regression demonstrated several significantly associated risks factors as follows: adjusted odds ratio for black race was 2.69; for residence of Illinois, 3.85; for not having health insurance, 1.57; for lack of a bachelors degree, 5.53; for having 2 to 15 partners, 1.60; for having ≥16 partners in previous year, 3.51; for being bisexual, 2.0; for not always using condoms, 3.04; and for having a partner who had a previous STI, 1.71. Age was not associated with trichomonas infection. All infected women were treated. Conclusions: A high prevalence of trichomonas and high sexual risk factors were demonstrated. Internet recruitment was a useful method of screening women for trichomonas infection.

Female users of internet-based screening for rectal STIs: descriptive statistics and correlates of positivity.

Background Submission of self-collected penile samples collected at home could remove barriers that men face in getting tested for sexually transmitted infections (STIs). Methods From December 2006 to July 2012, sexually active men aged ≥14 years were recruited by an educational internet program (http://www.iwantthekit.org) which offered free testing for Trichomonas vaginalis infection. Kits were ordered online and swabs were sent via US mail to the laboratory and tested by nucleic acid amplification tests. Demographics and sexual risk factors were accessed by questionnaires. Men called or were contacted to receive their results. Risk factors for trichomonas infection were determined by multivariate logistic regression Results Of 4398 men requesting kits, 1699 (38.6%) returned swabs by mail (55.4% returned in 2012). Forty-one percent of men were aged <25 years, 43% were black subjects and 45% were white. The overall prevalence for trichomonas in the 1699 men was 3.7%; the highest prevalence by age group was for men aged 40–49 years (5.2%) and, by year, 216 men screened in 2008 had the highest prevalence (12.5%). Risk factors for 919 men whose risk information was collected by questionnaire (prevalence 6.0%) indicated that 9.6% had a concurrent chlamydia infection. Significantly associated risks factors included: black race (adjusted OR 2.67), residence in Illinois (OR 12.02), age 30–39 years (OR 6.63) and age >40 years (OR 5.31). Conclusions A fairly high prevalence of trichomonas and sexual risk factors were demonstrated from internet recruitment of men. This method of engaging men to get screened for trichomonas may augment screening in STI clinics.