Nicole Quinn

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.

Can E-Technology Through the Internet be Used as a New Tool to Address the Chlamydia trachomatis Epidemic by Home Sampling and Vaginal Swabs?

The Internet provides patients, as well as clinicians with immediate, confidential access to information about sexually transmitted diseases (STDs).1,2 Young individuals are avid users of the Internet and usage has been considered to be a risk factor for STDs.3–7 Data indicate that there are 246,402,574 North American Internet users.8

Utilising the internet to test for sexually transmitted infections: results of a survey and accuracy testing

Background Searching the internet for information about sexually transmitted infections (STI) is common. The goal of the study was to discover which internet sites offer STI tests and obtain information about the services and their validity. Methods Using internet web-based search engines, information was collected from the sites about STI testing services, costs and types of tests offered, and tests were evaluated for accuracy. ‘Business’ functions regarding consent and return of results were investigated. Contact attempts were made by phone, e-mail or ‘contact us’ links and by mail. Test kits were ordered from six commercial internet sites and one public health site. Their accuracy was evaluated for chlamydia and gonorrhoea. Results The study identified 27 national/international internet sites offering STI self-collection kits and services. Tests were available for gonorrhoea, syphilis, chlamydia, HIV, herpes, hepatitis viruses, trichomonas, mycoplasma and ‘gardnerella’. All attempts to administer the survey yielded unsatisfactory results. After sending the survey by mail/e-mail to all the sites, four responded, two with the survey. Six websites appeared invalid based on non-deliverable e-mails and returned letters. The remainder did not respond. Test results were obtained from five of seven ordered kits. Two websites who were sent mocked urine specimens never provided results. The two ‘perform-it-yourself’ kits yielded false-negative results. Two mail-in urine specimens yielded correct positive results. The public health site kit yielded correct positive results. Conclusions The internet STI testing sites were difficult to contact and demonstrated unwillingness to answer consumer-specific questions. Test accuracy varied, with home tests having poor accuracy and mail-in specimens demonstrating high accuracy.

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

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.

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

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.

The Effect of Medical Male Circumcision on Urogenital Mycoplasma genitalium among Men in Kisumu, Kenya

Background: We determined the prevalence of urethral Mycoplasma genitalium (MG) infection and whether infection was associated with circumcision status among men enrolled in the randomized trial of medical male circumcision to prevent HIV acquisition in Kisumu, Kenya. Methods: MG and Trichomonas vaginalis were detected in first void urine by APTIMA transcription-mediated amplification assay. first void urine and urethral swabs were assessed for Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) by polymerase chain reaction assay. Herpes simplex virus type 2 antibodies were detected by IgG ELISA. Multivariable logistic regression identified factors associated with MG infection. Results: Specimens were collected between July and September 2010, and 52 (9.9%; 95% confidence interval [CI]: 7.3%–12.4%) MG infections were detected among 526 men. N. gonorrhoeae and T. vaginalis were not associated with MG. CT coinfection was 5.8% in MG-infected men, and 0.8% among MG-uninfected men (P = 0.02). MG infection was predominantly asymptomatic (98%). The prevalence of MG was 13.4% in uncircumcised men versus 8.2% in circumcised men (P = 0.06). Being circumcised nearly halved the odds of MG (adjusted odds ratio [aQR] = 0.54; 95% CI: 0.29–0.99), adjusted for other variables significant at the P < 0.05 level: herpes simplex virus type 2 infection (aOR = 2.05; 95% CI: 1.05–4.00), CT infection (aOR = 2.69; 95% CI: 1.44–5.02), and washing the penis ⩽1 hour after sex (aOR = 0.47; 95% CI: 0.24–0.95). Conclusions: MG infection was reduced among men who were circumcised, adding to the benefits of male circumcision in preventing several sexually transmitted infections.

Comparison of self-obtained penile-meatal swabs to urine for the detection of C. trachomatis, N. gonorrhoeae and T. vaginalis

Background Self-obtained penile-meatal swabs and urine specimens have been used for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) for outreach screening in men. Objective To compare the sensitivity of self-collected male penile-meatal swabs and urine for the detection of CT, NG and TV. Methods Matching penile-meatal swabs and urines were collected at home after recruitment to the study; via the internet programme, http://www.iwantthekit.org. The instructions directed the participant to place the tip of a Copan flocked swab at the meatal opening of the urethra to collect the penile-meatal sample. Two ml of urine was collected after the swab onto a Copan sponge-on-a-shaft collection device. Both swab and urine were placed into individual Aptima transport media tubes and mailed to the laboratory for testing. All specimens were tested for CT and NG using the GenProbe Aptima Combo2 Assay and for TV using GenProbe Aptima Analyte Specific Reagents with TV oligonucleotides. Results Of 634 men, 86 (13.6%) were positive for CT, 9 (1.4%) were positive for NG and 56 (9.3%) positive for TV. For CT, swab sensitivity was 81/86 (94.2%), and urine sensitivity was 66/86 (76.7%). For NG, swab sensitivity was 9/9 (100%) and urine sensitivity was 8/9 (88.9%). For TV, swab sensitivity was 45/56 (80.4%) and urine sensitivity was 22/56 (39.3%). Conclusions Self-obtained penile-meatal swabs provided for the detection of more CT, NG and TV, than urine specimens.

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

Professional organizations recommend rescreening chlamydia-infected women. The iwantthekit Internet-screening programme offered rescreening opportunities by using iwantthekit. Mailed, home-collected vaginal swabs were tested for chlamydia, gonorrhoea, and trichomoniasis by nucleic acid amplification tests. Demographics and risk behaviours of repeat users were determined from questionnaires. Predictors of repeat users were measured in a matched case–control study. Of 1747 women, 304 (17%), who used iwantthekit, indicated they had used the kit previously. Mean age was 24.7 ± 5.7 years and 69% were African-American. Repeat iwantthekit users were more likely to be aged ≥20 years (OR = 2.10); were more likely to have been treated for a sexually transmitted infection (OR = 2.32); less likely to drink alcohol before sex (OR = 0.63); and to never use condoms (OR = 0.43). Of repeat users, 84.2% had a negative prior test and 15.8% had a positive. At current test, 13.2% were infected. Previous trichomoniasis was associated with current trichomoniasis (p < 0.05). The iwantthekit may offer rescreening opportunities for previously infected women.

Chlamydia trachomatis Age-Specific Prevalence in Women Who Used an Internet-Based Self-screening Program Compared to Women Who Were Screened in Family Planning Clinics

Objectives: To determine whether women who collect self-collected vaginal swabs at home demonstrated a higher positivity of Chlamydia trachomatis than women in family planning clinics. Methods: Collection kits for vaginal swabs were internet requested, collected at home, and mailed to a laboratory for testing; questionnaires were completed about acceptability and sexual risk history. Infected women received treatment at participating clinics. Age-specific prevalences were compared to those from family planning clinics. Results: Chlamydia positivity was 10.3% for 1171 females mailing swabs; prevalences ranged from 3.3% to 5.5% in family planning. Positivity for internet age groups was much higher than those for family planning age groups. The positivity for internet participants ranged from a low of 4.4% in Baltimore in 2005 to a high of 15.2% Baltimore in 2007. Family planning clinic prevalence in Baltimore and Maryland ranged from a low of 3.3% in Baltimore in 2006 to a high of 5.5% in Baltimore in 2008. The median age for all years for internet users in Baltimore and Maryland combined was 23 years; the median age for all years for attendees to family planning clinics who had chlamydia testing performed was 23 years. Conclusions: Internet recruited women demonstrated higher positivity of chlamydia than those in family planning, providing new options for chlamydia screening programs.