American College of Preventive Medicine practice policy statement: screening for Chlamydia trachomatis

Incident Chlamydia trachomatis Infection in a High School Population

Prospective cohort studies of sexually transmitted infections (STIs) are logistically impractical owing to time and expenses. In schools, students are readily available for school-related follow-ups and monitoring. Capitalizing on the logistics that society already commits to ensure regular attendance of adolescents in school, a school-based STI screening in New Orleans made it possible to naturally observe the occurrence of chlamydia and to determine its incidence among 14-19-year-old adolescents. Among participants screened repeatedly, we calculated incidence rates, cumulative incidence, and incidence times. Male (n = 3820) and female (n = 3501) students were observed for 6251 and 5143 person-years, respectively, during which 415 boys and 610 girls acquired chlamydia. Incidence rates per 100 person-years were 6.6 cases for boys and 11.9 cases for girls. In multivariable analysis, the adjusted hazard ratio was 5.34 for boys and 3.68 for girls if the student tested positive for gonorrhea during follow-up, and 2.76 for boys and 1.59 for girls if at first participation the student tested positive for chlamydia, and it increased with age among boys but not among girls. In joinpoint trend analysis, the annual percentage change in the incidence rate was 6.6% for boys (95% CI: -1.2%, 15.1%) and 0.1% for girls (95% CI: -5.3%, 5.7%). Annual cumulative incidence was 5.5% among boys and 8.6% among girls. Median incidence time was 9.7 months for boys and 6.9 months for girls. Our findings can be used to refine assumptions in mathematical modeling and in cost analysis studies of C. trachomatis infection, and provide strong evidence in support of annual chlamydia screening for adolescent boys.

Examining sociodemographic risk factors for Chlamydia trachomatis infection: a population-based cohort study

AIM

Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection in developed nations and is an important public health concern. We aimed to assess the factors associated with testing and positivity of C. trachomatis in a large population.

METHODS

A retrospective study of a large Canadian health region was undertaken using 2011 census and laboratory data. Demographic and socioeconomic data from the national household survey were linked to microbiologic data for C. trachomatis. Multivariable generalized estimating equation models were constructed to examine relative risk for C. trachomatis testing and positivity.

RESULTS

For testing and positivity, female sex and younger age groups were associated with increased risk. University education and South Asian ethnicity were associated with lower risk of positivity.

CONCLUSION

Incorporating socio-demographic factors will be critical to the success of future sexually transmitted infection public health programs.

Examining Chlamydia trachomatis and Neisseria gonorrhoeae rates between 2010 and 2015: a population-based observational study

Bacterial sexually transmitted infections including Chlamydia trachomatis and Neisseria gonorrhoeae remain an important public health concern. We aimed to assess the population-based incidence of C. trachomatis and N. gonorrhoeae in an age-standardized cohort over time. A retrospective study of a large Canadian health region was undertaken between 2010 and 2015 using linked census and digital laboratory data. C. trachomatis and N. gonorrhoeae tests were linked to patient data. Sex and age-standardized incidence rates (IR) and ratios (IRR) were calculated for cases and testing rates. The annual mean population was 1,150,556 individuals (50.1% female). A total of 15,109 cases of chlamydia and 981 cases of gonorrhoea occurred. The overall IR for chlamydia ranged from 18.81 to 25.63 cases per 10,000 person-years. The IRR was 1.27 (95% CI 1.20-1.34, p < 0.001) for the comparison of 2015 and 2010 rates. For gonorrhoea, overall rates ranged from 0.92 to 1.86 cases per 10,000 person-years. The IRR for gonorrhoea was 2.02 (95% CI 1.56-2.59, p < 0.001) for 2015 and 2010 rates. In our large population-based study spanning six years, we observed increasing rates of C. trachomatis and N. gonorrhoeae with low testing rates.

Comparative effectiveness and acceptability of home-based and clinic-based sampling methods for sexually transmissible infections screening in females aged 14-50 years: a systematic review and meta-analysis

BACKGROUND

Home-based sampling is a strategy to enhance uptake of sexually transmissible infection (STI) screening. This review aimed to compare the screening uptake levels of home-based self-sampling and clinic-based specimen collection for STIs (chlamydia (Chlamydia trachomatis), gonorrhoea (Neisseria gonorrhoeae) and trichomoniasis) in females aged 14-50 years. Acceptability and effect on specimen quality were determined.

METHODS

Sixteen electronic databases were searched from inception to September 2012. Randomised controlled trials (RCTs) comparing the uptake levels of home-based self-sampling and clinic-based sampling for chlamydia, gonorrhoea and trichomoniasis in females aged 14-50 years were eligible for inclusion. The risk of bias in the trials was assessed. Risk ratios (RRs) for dichotomous outcomes were meta-analysed.

RESULTS

Of 3065 papers, six studies with seven RCTs contributed to the final review. Compared with clinic-based methods, home-based screening increased uptake significantly (P=0.001-0.05) in five trials and was substantiated in a meta-analysis (RR: 1.55; 95% confidence interval: 1.30-1.85; P=0.00001) of two trials. In three trials, a significant preference for home-based testing (P=0.001-0.05) was expressed. No significant difference was observed in specimen quality. Sampling was rated as easy by a significantly higher number of women (P=0.01) in the clinic group in one trial.

CONCLUSIONS

The review provides evidence that home-based testing results in greater uptake of STI screening in females (14-50 years) than clinic-based testing without compromising quality in the developed world. Home collection strategies should be added to clinic-based screening programs to enhance uptake.

Self-reported Chlamydia testing rates of sexually active women aged 15-25 years in the United States, 2006-2008

Using the 2006-2008 National Survey of Family Growth, we estimated a 37.9% annual chlamydia testing rate for sexually active US women aged 15 to 25 years, defined as having ≥ 1 sex partner in the past year. Our results highlight the need for increased testing among sexually active young women.

"Pee-in-a-Pot": acceptability and uptake of on-site chlamydia screening in a student population in the Republic of Ireland

BACKGROUND

The aim of the study was to explore the acceptability and uptake of on-campus screening using a youth friendly approach in two Third Level higher education institutions (HEIs). This study is part of wider research exploring the optimal setting for chlamydia screening in Ireland.

METHODS

Male and female students were given the opportunity to take a free anonymous test for chlamydia during a one week programme of "pee-in-a-pot" days at two HEI campuses in the West of Ireland. The study was set up after extensive consultation with the two HEIs and advertised on the two campuses using a variety of media in the two weeks preceding the screening days. Screening involved the provision and distribution of testing packs at communal areas and in toilet facilities. In Ireland, chlamydia notifications are highest amongst 20-29 year olds and hence the screening criterion was aimed at 18-29 year olds. Urine samples were tested using a nucleic acid amplification test (NAAT). Following the screening days, qualitative in-depth interviews were conducted with participants about their experiences of the event.

RESULTS

Out of 1,249 test kits distributed in two HEIs, 592 specimens were collected giving a return rate of 47.5%. Tests excluded (54) were due to labelling errors or ineligibility of participants' age. Two thirds of those tested were females and the mean age was 21 years. Overall, 3.9% (21/538) of participants tested positive, 5% (17/336) among females and 2% (4/191) among males. Participant interviews identified factors which enhanced student participation such as anonymity, convenience, accessibility of testing, and the informal and non-medical approach to testing.

CONCLUSIONS

Screening for chlamydia using on-campus "pee-in-a-pot" days is an acceptable strategy in this population. This model can detect and treat asymptomatic cases of chlamydia and avoid many of the barriers associated with testing for sexually transmitted infections (STIs) in clinical settings.

Assessing the impact of state insurance policies on chlamydia screening: A panel data analysis

OBJECTIVES

In the late 1990s, three Southern states (Maryland (MD), Georgia (GA) and Tennessee (TN)) enacted laws that required health plans to reimburse for chlamydia screening for the populations at risk. We assessed the impact of the laws on chlamydia screening rates for Georgia (GA) and Tennessee (TN).

METHODS

We extracted monthly chlamydia screening rates on employer-sponsored privately insured women and used a panel regression analysis to conduct an intervention analysis that compared changes in screening rates in Georgia and Tennessee to ten southern states, based on the dates that the laws were enacted in the two states. Maryland was excluded due to non-specificity of the law and insufficient data.

RESULTS

Although there were substantial increases in screening rates in both GA and TN after the enactment of the laws, data from the other ten states showed similar increases over the same period. Thus, there was no significant difference in the increase in screening rates between Georgia and Tennessee and the other states.

CONCLUSION

Because this analysis was restricted to privately insured patients, additional studies are needed to assess the effectiveness (or the lack thereof) of the laws for other populations, such as those covered by Medicaid, within the individual states.

Monitoring county-level chlamydia incidence in Texas, 2004 - 2005: application of empirical Bayesian smoothing and Exploratory Spatial Data Analysis (ESDA) methods

BACKGROUND

Chlamydia continues to be the most prevalent disease in the United States. Effective spatial monitoring of chlamydia incidence is important for successful implementation of control and prevention programs. The objective of this study is to apply Bayesian smoothing and exploratory spatial data analysis (ESDA) methods to monitor Texas county-level chlamydia incidence rates by examining spatiotemporal patterns. We used county-level data on chlamydia incidence (for all ages, gender and races) from the National Electronic Telecommunications System for Surveillance (NETSS) for 2004 and 2005.

RESULTS

Bayesian-smoothed chlamydia incidence rates were spatially dependent both in levels and in relative changes. Erath county had significantly (p < 0.05) higher smoothed rates (> 300 cases per 100,000 residents) than its contiguous neighbors (195 or less) in both years. Gaines county experienced the highest relative increase in smoothed rates (173% - 139 to 379). The relative change in smoothed chlamydia rates in Newton county was significantly (p < 0.05) higher than its contiguous neighbors.

CONCLUSION

Bayesian smoothing and ESDA methods can assist programs in using chlamydia surveillance data to identify outliers, as well as relevant changes in chlamydia incidence in specific geographic units. Secondly, it may also indirectly help in assessing existing differences and changes in chlamydia surveillance systems over time.

Sexually transmitted infections and pelvic inflammatory disease in women

Sexually transmitted infections (STIs) are an important public health challenge in the United States. Primary care clinicians can contribute to decreasing these largely preventable causes of morbidity and mortality by integrating routine screening, testing, counseling, treatment, and partner management of STIs into their practice. Newer tests for chlamydia and gonorrhea that can be performed on urine specimens allow screening without a pelvic examination. The most recent edition of the Centers for Disease Control and Prevention sexually transmitted disease treatment guidelines provides an evidence-based, reliable, and convenient set of recommendations for treating and caring for patients who have STIs.

Feasibility of conducting a large, randomized controlled trial for STD counseling in a managed care setting

BACKGROUND

Screening for, and prevention of, sexually transmitted diseases requires access to the adolescent, which is often difficult. The primary care visit can offer an opportunity to provide prevention counseling to adolescents. The objective of this study was to determine the feasibility of conducting a large randomized, controlled trial of sexually transmitted diseases counseling intervention in a managed care setting.

METHODS

A randomized, controlled trial of a counseling intervention was compared with usual care in a managed care organization in a southeastern United States urban area. Members aged 14- to 25-years old who tested positive for gonorrhea or chlamydia during the study period were randomized to receive either a two-part brief counseling intervention or usual care.

RESULTS

Among 93 members who tested chlamydia- or gonorrhea-positive and who were eligible to enroll, contact could not be made for 47 members, and only 12 of the remaining members enrolled in the study.

CONCLUSIONS

It would be problematic to implement a full-scale trial of this intervention in this practice environment without significant changes in clinical and intervention processes. The need for counseling services for sexually transmitted diseases remains great.

Estimating Chlamydia Screening Rates by Using Reported Sexually Transmitted Disease Tests for Sexually Active Women Aged 16 to 25 Years in the United States

OBJECTIVE

The objective of this study was to estimate Chlamydia trachomatis (CT) screening rates by using reported sexually transmitted disease (STD) tests for sexually active women aged 16 to 25 years in the U.S. general population.

METHODS

We analyzed data from the 2002 National Survey of Family Growth. Women were classified as sexually active if they reported having at least one male sex partner in the 12 months before the interview date. Women were classified as tested if they reported being tested for STDs by a healthcare provider in the preceding 12 months.

RESULTS

Of 2,563 sampled women aged 16 to 25 years, 75% were estimated to be sexually active. Of sexually active women, 42% reported they had been tested for STDs and 73% reported they had received Pap smears or pelvic examinations in the preceding 12 months.

CONCLUSIONS

Even if all women tested for STDs were screened for CT, only 42% of sexually active women aged 16 to 25 years would have been screened for CT. CT screening rates could be significantly increased if CT tests were performed when women had Pap smears or pelvic examinations, because most sexually active women have routine Pap smears or pelvic examinations.

Home screening for sexually transmitted diseases in high-risk young women: randomised controlled trial

OBJECTIVE

Home screening tests could eliminate several barriers to testing sexually transmitted diseases (STDs).

AIM

To determine whether offering repeated home screening tests would increase the rate of testing for chlamydia and gonorrhoea in a high-risk sample of young women.

METHODS

In this randomised controlled trial, 403 young women (mean age 18.9 years, 70% black) with a recent STD or with STD-related risk factors were enrolled. Participants were recruited from clinics and high-prevalence neighbourhoods and then randomly assigned to receive either a home testing kit or an invitation to attend a medical clinic for testing at 6, 12 and 18 months after enrollment. Over 80% of women were followed for 2 years. The trial is registered with ClinicalTrials.gov, number NCT 00177437.

RESULTS

Of 197 women in the intervention group, 140 (71%) returned at least one home test and 25 of 249 (10%) home tests were positive. Women who received home screening tests completed significantly more STD tests overall (1.94 vs 1.41 tests per woman-year, p<0.001) and more STD tests in the absence of symptoms (1.18 vs 0.75 tests per woman-year, p<0.001). More women in the intervention group completed at least one test when asymptomatic (162 (82.2%) vs 117 (61.3%), p<0.001). The intervention was most effective among women recruited outside medical clinics. There was no significant difference in the overall rate of STDs detected.

CONCLUSIONS

Home screening significantly increased the utilisation of chlamydia and gonorrhoea testing in this sample of high-risk young women, and thus represents a feasible strategy to facilitate STD testing in young women.

Comparison of self-reported and test-identified chlamydial infections among young adults in the United States of America

BACKGROUND

Many studies rely on respondent reports of prior diagnosed sexually transmissible infections (STIs), but these self reports are likely to under-estimate infection prevalence. The extent of bias from using self-reported STI data, and whether bias varies by sex and race, is largely unknown. This gap is addressed using a large, nationally representative sample.

METHODS

Cross-sectional analyses of Wave III of the National Longitudinal Study of Adolescent Health. Participants were 18-26 years old (n = 12,359). Estimates of the prevalence of chlamydial infection based on self-reported diagnoses in the past year were compared with actual prevalence based on nucleic acid amplification testing (NAAT) at the time of data collection. Ratios of test-identified prevalence to self-reported diagnosis prevalence were calculated by sex and race/ethnicity groups. Larger ratios indicate greater extent of self reports under-estimating infection prevalence.

RESULTS

About 4.2% of the sample had a current NAAT-identified chlamydial infection, but only 3.0% reported having been diagnosed with chlamydia in the past year, yielding a ratio of 1.43. The ratio of test-identified infection prevalence to prevalence identified from self-reported diagnoses was larger among men than women (2.07 versus 1.14, P < 0.05). Among men, the ratio was larger among non-Hispanic blacks (2.40) compared with non-Hispanic whites (1.07, P < 0.05).

CONCLUSIONS

Use of self-reported diagnoses under-estimates chlamydial infection prevalence, particularly among men, and among non-Hispanic black men. Reliance on self-reported STIs may consequently lead to biased conclusions, particularly for these groups. Use of biological testing for STIs in research studies is recommended.

The cost effectiveness of screening for genital Chlamydia trachomatis infection in Australia

Background: In Australia, there is no published study on the cost effectiveness of screening for chlamydia. The aim of this study was to examine the cost effectiveness of a hypothetical screening programme for chlamydia based on annual opportunistic testing of all women 25 years of age or younger consulting a general practitioner, compared with no screening. Methods: A decision–analytic modelling approach was used to determine the incremental cost effectiveness ratio (ICER) of screening compared with no screening over 25 years. The analysis measured Australian health-care costs and benefits were assessed in terms of quality-adjusted life years (QALYs). Results: The analysis resulted in a cost per QALY of $2968 for screening. One-way sensitivity analyses on all variables, and multi-way sensitivity analyses on some variables, showed a wide range for the cost effectiveness, from dominance (where screening is effective and saves money overall) to an ICER of $67 715 per QALY. Conclusions: The results indicate that annual opportunistic screening for chlamydia in women under 25 is a potentially worthwhile undertaking. However, the analysis also highlights uncertainties around the natural history of chlamydia and the effectiveness of chlamydia screening. Given these uncertainties, the need for further primary data collection in these areas becomes apparent.

Is provider continuity associated with chlamydia screening for adolescent and young adult women?

BACKGROUND

Longitudinal patient-provider relationships are a cornerstone of primary care. For many prevention services, better continuity of provider has been associated with better adherence to recommended practice. Our objective was to examine the relationship between continuity of care and chlamydia screening in adolescent and young women, a preventive service where large performance gaps exist.

METHODS

The study population included 4117 sexually active women aged 14-25 years continuously enrolled at a large U.S. HMO. Administrative data from 2000 to 2002 were used to document chlamydia testing, provider continuity, and selected covariates. We used logistic regression to examine the relationship between provider continuity and chlamydia testing after controlling for potential confounders.

RESULTS

57.2% of eligible young women received a chlamydia test over the 2-year period. After controlling for utilization and other confounders, we found women in the lowest continuity of care quartile had 41% greater odds of being tested than those in the highest quartile (OR 1.41, 95% CI 1.14-1.76).

CONCLUSIONS

For adolescents and young women, the likelihood of testing for chlamydia was reduced when care was concentrated with a usual provider. Potential implications for health service delivery are discussed.

Epidemiology of chlamydial infection, gonorrhea, and trichomoniasis in the United States--2005

The prevalence and incidence of chlamydial infection, gonorrhea, and trichomoniasis are unacceptably high in the United States. The prevalence of gonorrhea is substantially lower than chlamydial infection and trichomoniasis; in part, this is presumably due to the greater frequency of symptomatic disease. The disparity between racial/ethnic groups is considerable for each of these infections. Greater effort must be devoted to reducing this disparity and to understanding the underlying mechanisms of disease persistence in the United States.

Nucleic acid amplification tests for gonorrhea and chlamydia: practice and applications

Nucleic acid amplification tests (NAATs), which are highly sensitive and specific, have provided the ability to use alternative sam-ple types for the diagnosis of sexually transmitted infections (STIs). Self-collected genital specimens, such as urine or even vaginal swabs, can now be accurately used to diagnose gonorrhea or chlamydia infections. In many cases, use of these sample types can decrease the necessity for a clinician to perform a pelvic examination on women or to collect a urethral swab from men, thus extending the diagnostic capability for detecting these infections to nonclinic screening venues. As most chlamydia infections and many gonorrhea infections are asymptomatic, the use of NAATs for self-collected samples greatly increases the types and numbers of patients that can be screened outside of clinic settings. Self-sampling also allows clinicians to easily screen patients in the clinic for STIs who are not presenting for pelvic or urogenital examinations. The application of NAATs to self-collected specimens has the potential to augment public health programs designed to control the epidemic of STIs in the community.

Chlamydia screening in a Health Plan before and after a national performance measure introduction

OBJECTIVE

To evaluate chlamydia-screening policies, testing practices, and the proportion testing positive in response to the new Health Plan Employer Data and Information Set (HEDIS) chlamydia-screening performance measure in a large commercial health plan.

METHODS

We interviewed health plan specialty departmental chiefs to describe interventions used to increase chlamydia screening and examined electronic medical records of 15- to 26-year-old female patients--37,438 from 1998 to 1999 and 37,237 from 2000 to 2001--who were classified as sexually active by HEDIS specifications to estimate chlamydia testing and positive tests 2 years before and after the HEDIS measure introduction.

RESULTS

In January 2000, the obstetrics and gynecology department instituted a policy to collect chlamydia tests at the time of routine Pap tests on all females 26 years old or younger by placing chlamydia swabs next to Pap test collection materials. Other primary care departments provided screening recommendations and provider training. During 1998-1999, 57% of eligible female patients seen by obstetrics and gynecology exclusively and 63% who were also seen by primary care were tested for chlamydia; in 2000-2001 the proportions tested increased to 81% (P < .001) and 84% (P < .001). Proportions tested by other primary care specialists did not increase substantially: 30% in 1998-1999 to 32% in 2000-2001. The proportion of females testing positive remained high after testing rates increased: 8% during 1998-1999 and 7% during 2000-2001, and the number of newly diagnosed females increased 10%.

CONCLUSION

After the obstetrics and gynecology department introduced a simple systems-level change in response to the HEDIS measure, the proportion of females chlamydia-tested and number of newly diagnosed females increased.

Urine nucleic acid amplification tests for the diagnosis of sexually transmitted infections in clinical practice

PURPOSE OF REVIEW

With the advent of highly sensitive and specific nucleic acid amplification assays, this report will demonstrate that self-collected genital specimens, such as urine or even vaginal swabs can be accurately used to diagnose sexually transmitted infections.

RECENT FINDINGS

Use of self collected samples can eliminate the necessity of a clinician to perform a pelvic examination for women or collect a urethral swab for men, thus extending the diagnostic capability for sexually transmitted infections to non-clinic screening venues. As many sexually transmitted infections are asymptomatic, this ability to use self-sampling greatly increases the numbers of patients that can be screened, and has the potential to augment public health programs designed to control the epidemic of sexually transmitted infections in the community. Patient collected samples are highly acceptable, highly accurate, and are becoming widely used. Self-sampling also allows clinicians to easily screen patients in the clinic, who are not presenting for pelvic or urogenital examinations, for sexually transmitted infections.

SUMMARY

Highly accurate molecular tests and easily obtained self-collected urogenital samples represent the ideal combination for obtaining the public health goal of decreasing the sexually transmitted infection epidemic among sexually active persons in the United States today.

Chlamydia-induced arthritis

PURPOSE OF REVIEW

Chlamydia-induced arthritis is the most frequent form of reactive arthritis in Western countries. This article gives an overview of the recent findings with respect to diagnosis, pathogenesis, and therapy of the disease.

RECENT FINDINGS

Recent advances in the modification and standardization of polymerase chain reaction techniques give promise to identify Chlamydia more frequently from joint samples. Based on the sequenced chlamydial genome, considerable progress has been achieved in the understanding of the Chlamydia-host cell interaction, indicating that persistence is an alternate state of the bacteria used by Chlamydia to escape the immune system of the host rather than a general stress response. Furthermore, Chlamydia has the ability to reprogram the host cell by chlamydial effector proteins, which are transported from the inclusion into the host cell cytoplasm. The role of HLA-B27 is discussed in view of the pathogenesis of the disease. HLA-B27 should be considered a risk factor for chronic and/or axial disease rather than a true susceptibility factor for the development of Chlamydia-induced arthritis. No progress has been made in terms of causative therapy aiming at eradication of the bacteria. Tumor necrosis factor-alpha blocking agents may represent a new option in cases that are refractory to therapy.

SUMMARY

Molecular biology not only has improved the ability to detect Chlamydia in the joint for diagnostic purposes but also has extended the current understanding of the pathogenesis of the disease. In contrast to this progress, causative therapy of Chlamydia-induced arthritis is still an unfulfilled need.

The tip of the iceberg: opportunistic screening for Chlamydia trachomatis in asymptomatic patients attending a young people's health clinic reveals a high prevalence — a pilot study

Objectives: We implemented an opportunistic screening programme for Chlamydia trachomatis amongst patients presenting to a young peoples’ health service in the city of Geelong, Australia, to define the prevalence of infection and to identify specific risk factors. Methods: Over a 7-month period sexually active patients attending the young peoples’ clinic were offered C. trachomatis screening by nucleic acid amplification test. There was 100% acceptance rate among those offered the test. Patient demographics, reason for presentation at the clinic and reported symptoms were documented by the clinicians and correlated with laboratory findings. Results: 163 patients between the ages of 12–25 were tested, nine males and 154 females. The prevalence of chlamydia infection was 5.8% and was highest (16.0%) among patients presenting for the morning after pill. Inhibition of the nucleic acid amplification test occurred in 11.0% of urine samples. All patients with inhibited tests were asked to provide a repeat sample for retesting, but only 50% complied with this request. The majority of repeat samples (88.9%) had no inhibitors present and yielded a negative result. There was no correlation between symptoms and a positive chlamydia result. Conclusions: Chlamydia infection is common in young people engaging in unsafe sexual practice and cannot be predicted by the presence of symptoms. The high prevalence of infection in Geelong would make screening cost effective in this age group. Ongoing population screening of sexually active young people should be encouraged in community health centres. Inhibition of the nucleic acid amplification test was common but repeat testing of urine a few days later usually gave satisfactory results.