Opportunistic Chlamydia Screening Research Articles

Chlamydia trachomatis: Management and screening

C hlamydia trachomatis is the most common sexually transmitted infection worldwide. In up to 50% of men and 70% of women, infection is asymptomatic or minimally symptomatic and can easily be missed. Untreated infection can cause significant morbidity including pelvic inflammatory disease and infertility. These harmful consequences occur predominantly in women. The UK National Chlamydia Screening Programme recommends opportunistic chlamydia screening for sexually active women who are less than 25 years old. This article provides a contemporary overview of chlamydia. Within this article, references to ‘women’ includes cisgender women and other people with a uterus or ovaries – including transgender men, non-binary people (assigned female at birth) and intersex people with a uterus or ovaries who have not had a hysterectomy or bilateral oophorectomy. ‘Men’ includes cisgender men as well as all other people with a penis and testes, including transgender women who have not had bilateral orchidectomy.

Modelling the impact of screening for chlamydia and gonorrhoea in youth and other high-prevalence groups in a resource-limited setting

ObjectivesModelling the potential impact of screening for chlamydia and gonorrhoea in youth and other populations in a resource-limited setting.MethodsWe extended an agent-based model of heterosexual chlamydia and gonorrhoea transmission in South Africa to investigate the impact of screening strategies in key populations including youth, patients in HIV care, pregnant women and female sex workers (FSWs). Additionally, we compared the modelled impact of a standardised screening programme to results obtained from other published mathematical models of chlamydia screening.ResultsAll strategies resulted in reductions in general and targeted population chlamydia and gonorrhoea transmission. Opportunistic screening of patients in youth and HIV care was shown to be the most effective, and FSW screening was shown to be the most efficient strategy. Differences between models could be attributed to differences in the modelled heterogeneity in sexual behaviour as well as differences in assumptions about immunity following chlamydia recovery.ConclusionsTaking modelling assumptions into account, opportunistic chlamydia and gonorrhoea screening of youth and those in HIV care represents a viable intervention for reducing sexually transmitted infections in the South African population.

Exploring why a complex intervention piloted in general practices did not result in an increase in chlamydia screening and diagnosis: a qualitative evaluation using the fidelity of implementation model

BackgroundChlamydia trachomatis (chlamydia) is the most commonly diagnosed sexually transmitted infection (STI) in England; approximately 70% of diagnoses are in sexually active young adults aged under 25. To facilitate opportunistic chlamydia screening in general practice, a complex intervention, based on a previously successful Chlamydia Intervention Randomised Trial (CIRT), was piloted in England. The modified intervention (3Cs and HIV) aimed to encourage general practice staff to routinely offer chlamydia testing to all 15–24 year olds regardless of the type of consultation. However, when the 3Cs (chlamydia screening, signposting to contraceptive services, free condoms) and HIV was offered to a large number of general practitioner (GP) surgeries across England, chlamydia screening was not significantly increased. This qualitative evaluation addresses the following aims:Explore why the modified intervention did not increase screening across all general practices.Suggest recommendations for future intervention implementation.MethodsPhone interviews were carried out with 26 practice staff, at least 5 months after their initial educational workshop, exploring their opinions on the workshop and intervention implementation in the real world setting. Interview transcripts were thematically analysed and further examined using the fidelity of implementation model.ResultsParticipants who attended had a positive attitude towards the workshops, but attendee numbers were low. Often, the intervention content, as detailed in the educational workshops, was not adhered to: practice staff were unaware of any on-going trainer support; computer prompts were only added to the female contraception template; patients were not encouraged to complete the test immediately; complete chlamydia kits were not always readily available to the clinicians; and videos and posters were not utilised. Staff reported that financial incentives, themselves, were not a motivator; competing priorities and time were identified as major barriers.ConclusionNot adhering to the exact intervention model may explain the lack of significant increases in chlamydia screening. To increase fidelity of implementation outside of Randomised Controlled Trial (RCT) conditions, and consequently, improve likelihood of increased screening, future public health interventions in general practices need to have: more specific action planning within the educational workshop; computer prompts added to systems and used; all staff attending the workshop; and on-going practice staff support with feedback of progress on screening and diagnosis rates fed back to all staff.

Chlamydia trachomatis Pgp3 Antibody Population Seroprevalence before and during an Era of Widespread Opportunistic Chlamydia Screening in England (1994-2012).

BackgroundOpportunistic chlamydia screening of <25 year-olds was nationally-implemented in England in 2008 but its impact on chlamydia transmission is poorly understood. We undertook a population-based seroprevalence study to explore the impact of screening on cumulative incidence of chlamydia, as measured by C.trachomatis-specific antibody.MethodsAnonymised sera from participants in the nationally-representative Health Surveys for England (HSE) were tested for C.trachomatis antibodies using two novel Pgp3 enzyme-linked immunosorbent assays (ELISAs) as a marker of past infection. Determinants of being seropositive were explored using logistic regression among 16–44 year-old women and men in 2010 and 2012 (years when sexual behaviour questions were included in the survey) (n = 1,402 women; 1,119 men). Seroprevalence trends among 16–24 year-old women (n = 3,361) were investigated over ten time points from 1994–2012.ResultsIn HSE2010/2012, Pgp3 seroprevalence among 16–44 year-olds was 24.4% (95%CI 22.0–27.1) in women and 13.9% (11.8–16.2) in men. Seroprevalence increased with age (up to 33.5% [27.5–40.2] in 30–34 year-old women, 18.7% [13.4–25.6] in 35–39 year-old men); years since first sex; number of lifetime sexual partners; and younger age at first sex. 76.7% of seropositive 16–24 year-olds had never been diagnosed with chlamydia. Among 16–24 year-old women, a non-significant decline in seroprevalence was observed from 2008–2012 (prevalence ratio per year: 0.94 [0.84–1.05]).ConclusionOur application of Pgp3 ELISAs demonstrates a high lifetime risk of chlamydia infection among women and a large proportion of undiagnosed infections. A decrease in age-specific cumulative incidence following national implementation of opportunistic chlamydia screening has not yet been demonstrated. We propose these assays be used to assess impact of chlamydia control programmes.

NH2 What effect do practice visits have upon opportunistic chlamydia screening test uptake and case detection in primary care? An audit of 81 general practices in Oxfordshire

Background/Introduction The National Chlamydia Screening Programme in England aims to reduce transmission and prevent complications through early diagnosis. The ‘Value for Money’ review proposed opportunistic screening in general practice supported by specialist services. Aims/Objectives To evaluate the effect of practice visits upon chlamydia screening coverage and case identification in young people aged 15–24 in Oxfordshire, April 2012–March 2014. Methods Quarterly counts of total screens and positive tests for general practices in Oxfordshire were linked to records of practice visits (date, attendance) and characteristics of practices (location, deprivation, practice size). Testing and positivity rates three months prior to screening officer visits (baseline) were compared to rates in the 0–3 and 4–6 months following a visit. Pre- and post-visit counts were compared using multivariate generalised estimating equation models, accounting for repeated measures by practices and confounders. Results Practice screen counts were available for 136 periods before and after visits to 81 practices. Practices reported a median of 9 tests in the 3 months prior to visits or 3% screening coverage of registered 15–24 year olds. Screen counts were significantly higher following visits (Table 1), and positively associated with higher staff attendance at those visits. Also, there is an increase in number of positive cases diagnosed immediately after visits. Conclusion Practice visits serve as a good reminder for staff in general practice to offer test opportunistically. However, there is a need for an enhanced intervention to sustain any increase in screening coverage and diagnoses following visit.

P100 Exploring why a complex intervention piloted in general practices did not result in an increase in chlamydia screening and diagnosis: a qualitative evaluation using the fidelity of implementation model

Background To facilitate opportunistic chlamydia screening in general practices, a complex intervention (3Cs and HIV), based on the previously successful CIRT trial, was implemented across England. The intervention, to encourage practice staff to routinely offer chlamydia testing, only increased chlamydia screening in larger practices or in those offered incentives. Aims a) Explore why the modified intervention did not increase screening across all general practices. b) Suggest recommendations for future intervention implementation. Methods Phone interviews were carried out with 26 GP staff exploring their opinions on the workshops and intervention implementation in practice. Interview transcripts were thematically analysed and further examined using the fidelity of implementation model. Results Participants were positive about the workshops but attendee numbers were low. Often, the intervention content was not adhered to: practice staff were unaware of any on-going trainer support; computer prompts were only added to the female contraception template; patients were not encouraged to complete the test immediately; and videos and posters were not utilised, as suggested. Staff reported that financial incentives, themselves, were not a motivator; competing priorities and time were identified as major barriers. Conclusions Not adhering to the exact intervention model may explain the lack of significant increases in chlamydia screening. To increase fidelity of implementation and consequently improve likelihood of increased screening, the intervention needs to have: more specific action planning; computer prompts added to systems and used; all staff attend the workshop; and on-going practice staff support.

Gonorrhoea Diagnostic and Treatment Uncertainties: Risk Factors for Culture Negative Confirmation after Positive Nucleic Acid Amplification Tests.

Gonorrhoea incidence has increased substantially in Stockholm during the past years. These increases have coincided with changes in testing practice from solely culture-based to nucleic acid amplification tests (NAAT). Gonorrhoea NAAT is integrated with Chlamydia trachomatis testing and due to opportunistic screening for chlamydia, testing prevalence for gonorrhoea has increased substantially in the Stockholm population. The aim of this study was to examine epidemiological risk-factors for discordant case which are NAAT positive but culture negative. These discordant cases are especially problematic as they give rise to diagnostic and treatment uncertainties with risk for subsequent sequelae. All gonorrhoea cases from Stockholm county during 2011–2012 with at least one positive N. gonorrhoea NAAT test and follow-up cultures were included (N = 874). Data were analysed using multivariate and stratified logistic regression models. Results showed that women were 4-times more likely (OR 4.9; 95% CI 2.4–6.7) than men to have discordant cultures. Individuals tested for gonorrhoea without symptoms were 2.3 times more likely (95% CI 1.5–3.5) than those with symptoms to be discordant. NAAT method and having one week or more between NAAT and culture testing were also indicative of an increased likelihood for discordance. Using NAAT should be based on proper clinical or epidemiological indications and, when positive, followed-up with a culture-based test within one week if possible. Routine gonorrhoea testing is not recommended in low prevalence populations.

Assessment of changes in the burden of Chlamydia trachomatis infection in the context of widespread opportunistic chlamydia screening: Pgp3 seroprevalence measured in a series of nationally representative cross-sectional household surveys

Abstract Background Opportunistic screening of people aged under 25 years for genital Chlamydia trachomatis infection (chlamydia) was nationally implemented in England in 2008, but its impact is poorly understood. Antibodies to C trachomatis persist after infection, thus providing a marker of past infection. We aimed to explore the effect of screening on cumulative incidence of chlamydia (incidence of infection by a given age), as measured by C trachomatis antibodies. Methods Anonymised serum samples from participants in the nationally representative Health Surveys for England (HSE) were tested for C trachomatis antibodies using two novel in-house Pgp3 ELISAs, which have demonstrated superior sensitivity to commercial assays. Determinants of being seropositive were explored with logistic regression among women (n=1402) and men (1119) aged 16–44 years in 2010–12 (years when questions about sexual behaviour were included in the survey). Seroprevalence trends among 16–24-year-old women (n=3361) were investigated over ten timepoints from 1994 to 2012. Findings During 2010–12, Pgp3 seroprevalence among participants aged 16–44 years was 24·4% (95% CI 22·0–27·1) in women and 13·9% (11·8–16·2) in men. Seroprevalence increased with age (up to 33·5% [27·5–40·2] in 30–34-year-old women; 18·7% [13·4–25·6] in 35–39-year-old men) and with years since first sexual intercourse (38·2% [32·0–44·7] in women and 22·3% [16·2–29·8] in men aged 15–19 years). Total number of lifetime sexual partners and younger age at first sex were significantly associated with being seropositive (>10 lifetime sexual partners vs 1–4: odds ratio 3·84 women [95% CI 2·68–5·51], 5·95 men [3·41–10·35]; vs >16: 2·26 women [1·61–3·16], 2·14 men [1·41–3·24]). 76·7% of seropositive 16–24-year-olds had never been diagnosed with chlamydia: among women, seroprevalence did not differ between the first (1994–96) and second (2001–02) periods sampled (prevalence ratio 1·04, 0·87–1·25); a non-significant decline was observed from 2008 to 2012 (prevalence ratio per year 0·94, 0·84–1·05). Interpretation Our application of Pgp3 ELISAs demonstrates a high lifetime risk of chlamydia among women and that a large proportion of infections go undiagnosed. A decrease in age-specific cumulative incidence after national implementation of opportunistic chlamydia screening has not yet been demonstrated. We propose that these assays be used more widely to assess the effect of chlamydia control programmes. Funding The Health Survey for England was funded by the Health and Social Care Information Centre. Testing of stored serum samples was funded by the Health Protection Agency (now Public Health England). The funders played no part in the design, conduct, analysis, or reporting of this study, or in the decision to submit the abstract for publication.

P08.32 The feasibility and acceptability of offering opportunistic chlamydia screening in a nurse-led primary health care clinic

Introduction Chlamydia rates are highest among young people. Screening is the best method of identifying asymptomatic infection. The study aim was to determine the feasibility and case finding effectiveness of routinely offered chlamydia screening in the nurse-led ACT Health Walk in Centre (WiC). Methods Regardless of the purpose of their visit, all WiC attendees aged 16–30 years were offered chlamydia screening. Cases were managed by CSHC. Outcome measures were: number of specimens collected, proportion of positive tests, proportion of cases treated at CSHC and contact tracing yield. Results 4341 people in the target age range (29.1% of total WiC presentations) attended between 13/8/12 and 31/5/13; 473 (10.9%) accepted screening. Screening was associated with female gender (293 vs. 180 p = 0.0001), 20–24 year age group and no particular reason for attendance. 28 (5.9%) tested positive (19 females, 9 males, 22 aged 16–25 years). 26/28 (92.9%) attended CSHC for treatment; 2 were treated elsewhere. 39 sexual partners were nominated by the 26 patients treated at CSHC; 23 were contacted by the index cases and 16 by CSHC staff. Conclusions Offering chlamydia screening to young people attending the WiC is feasible and demonstrated excellent case finding effectiveness. Efforts to increase screening participation are needed. Disclosure of interest statement This project was funded by ACT Health, Population Health Division. No Pharmaceutical grant was received in the development of this study.

Is chlamydia screening and testing in Britain reaching young adults at risk of infection? Findings from the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3)

BackgroundIn the context of widespread opportunistic chlamydia screening among young adults, we aimed to quantify chlamydia testing and diagnosis among 16–24 year olds in Britain in relation to risk factors...

Increasing chlamydia screening tests in general practice: a modified Zelen prospective Cluster Randomised Controlled Trial evaluating a complex intervention based on the Theory of Planned Behaviour

ObjectiveTo determine if a structured complex intervention increases opportunistic chlamydia screening testing of patients aged 15–24 years attending English general practitioner (GP) practices.MethodsA prospective, Cluster Randomised Controlled Trial with a...

P5.017 The Australian Chlamydia Control Effectiveness Pilot (ACCEPt): Early Results from a Randomised Trial of Annual Chlamydia Screening in General Practise

BackgroundACCEPt is a cluster randomised controlled trial to evaluate annual opportunistic chlamydia screening for 16–29 year olds in general practise (GP). Towns in which GP clinics are enrolled, are randomised...

Chlamydia testing and retesting patterns at family planning clinics in Australia

National guidelines recommend opportunistic chlamydia screening of sexually active 16- to 29-year-olds and encourage retesting 3-12 months after a diagnosed chlamydia (Chlamydia trachomatis) infection. We assessed chlamydia testing patterns at five Australian family planning clinics (FPCs). Using routine clinic data from 16- to 29-year-olds, we calculated chlamydia testing and positivity rates in 2008-2009. Reattendance, retesting and positivity rates at retesting within 1.5-4 and 1.5-12 months of a positive result were calculated. Over 2 years, 13?690 individuals aged 16-29 years attended five FPCs (93% female). In 2008, 3159 females (41.4%,) and 263 males (57.0%) were tested for chlamydia; positivity was 8% and 19%, respectively. In 2009, 3178 females (39.6%) and 295 males (57.2%) were tested; positivity was 8% and 23%, respectively. Of 7637 females attending in 2008, 38% also attended in 2009, of which 20% were tested both years. Within 1.5-4 months of a positive test, 83 (31.1%) females reattended; the retesting rate was 13% and 12% retested positive. Within 1.5-12 months of a positive test, 96 (57.5%) females reattended; the retesting rate was 36% and 13% retested positive. Approximately 40% of young people attending FPCs were tested for chlamydia but a smaller proportion were tested annually or were retested following chlamydia infection. High positivity rates emphasise that FPCs see a high-risk population. To maximise testing opportunities, clinical prompts, patient reminder systems and non-clinic testing strategies may be needed.

O8 The Australian chlamydia control effectiveness pilot (ACCEPt): first results from a randomised trial of annual chlamydia screening in general practice

BackgroundACCEPt is a cluster randomised controlled trial to evaluate annual opportunistic chlamydia screening for 16–29-year-old men and women in general practice (GP).ObjectiveTo report enrolment and baseline results.MethodsThe unit of randomisation...

Exploring attitudes and practices of General Practice staff towards offers of opportunistic screening for chlamydia: a UK survey

This study applied a theory-based questionnaire to examine the behaviours and beliefs of all practice staff who may be involved in offering chlamydia screens to young people aged 15-25 years old. We aimed to identify potential influencing factors and examine the organisational constraints, which may be amenable to change. The National Chlamydia Screening Programme offers opportunistic screening to men and women between 15 and 25 years old who have ever had sexual intercourse and primary care is the second largest source of screens. In England 15.9% of the target group were screened against a target of 17% in 2008. Interventions to improve the frequency of offers have shown effects with volunteer practices. A survey of 85 General Practices was completed by 55 doctors, nurses and receptionists. Interviews were conducted with 12 staff from three practices. Respondents were unable to identify the national screening target. Only half record if a patient is sexually active. Half the sample had some recollection of the frequency of offers they made, with a mean of 4 per month. These were predominantly in consultations concerning sexual health. Perceived social norms are favourable to screening and respondents have strong perceived control over offering screens, including to those under 16 who are sexually active. Attitudes towards screening were positive but disadvantages and barriers related to increased pressure on practice resources for longer consultations and contact tracing. There were no differences in beliefs and practice behaviours between medical and nursing staff. Future interventions should be targeted at increasing the range of consultations in which offers are made, demonstrating how to make offers without increasing consultation time, providing more complete records of sexual activity, screens and results, and encouraging audit and review within the practice to promote practice wide approaches to increasing opportunistic screening.

The cost and cost-effectiveness of opportunistic screening for Chlamydia trachomatis in Ireland

ObjectiveThe objective of this study was to estimate the cost and cost-effectiveness of opportunistic screening for Chlamydia trachomatis in Ireland.MethodsProspective cost analysis of an opportunistic screening programme delivered jointly in...

P1-S6.16 Australian chlamydia control effectiveness pilot: preliminary results from a trial of chlamydia testing in general practice

BackgroundWhile opportunistic chlamydia screening is conducted in several countries, debate remains about the effectiveness of population-based screening programs for reducing chlamydia transmission and its morbidity. The Australian Chlamydia Control Effectiveness...

Where do young adults want opportunistic chlamydia screening services to be located?

This study measured the acceptability of urine-based chlamydia screening to young adults, where young adults wanted opportunistic chlamydia screening services to be located, and by whom they wanted to be offered screening. A cross-sectional survey of 5685 university students and 400 young adult healthcares setting attendees (age: 18-29 years). Ninety-six percent of males and 93% of females said that they would find it acceptable to be offered chlamydia screening. Seventy-six percent of males and 77% of females wanted to be offered screening by a doctor or nurse. Young women would prefer female staff. Most respondents preferred that screening be located in traditional healthcare settings such as General Practices, and offered by either doctors or nurses. More than 90% of respondents did not want screening services to be located in pharmacies and almost all rejected public non-health care screening settings. Opportunistic chlamydia screening services should be located in traditional healthcare/medical settings, and screening should be offered by doctors and nurses.

"...they should be offering it": a qualitative study to investigate young peoples' attitudes towards chlamydia screening in GP surgeries

BackgroundDespite the known health and healthcare costs of untreated chlamydia infection and the efforts of the National Chlamydia Screening Programme (NCSP) to control chlamydia through early detection and treatment of asymptomatic infection, the rates of screening are well below the 2010-2011 target rate of 35%. General Practitioner (GP) surgeries are a key venue within the NCSP however; previous studies indicate that GP surgery staff are concerned that they may offend their patients by offering a screen. This study aimed to identify the attitudes to, and preferences for, chlamydia screening in 15-24 year old men and women attending GP surgeries (the target group).MethodsWe undertook 36 interviews in six surgeries of differing screening rates. Our participants were 15-24 year olds attending a consultation with a staff member. Data were analysed thematically.ResultsGP surgeries are acceptable to young people as a venue for opportunistic chlamydia screening and furthermore they think it is the duty of GP surgery staff to offer it. They felt strongly that it is important for surgery staff to have a non-judgemental attitude and they did not want to be singled out as 'needing' a chlamydia screen. Furthermore, our sample reported a strong preference for being offered a screen by staff and providing the sample immediately at the surgery rather than taking home a testing kit. The positive attitude and subjective norms demonstrated by interviewees suggest that young peoples' behaviour would be to accept a screen if it was offered to them.ConclusionYoung people attending GP surgeries have a positive attitude towards chlamydia screening and given the right environment are likely to take up the offer in this setting. The right environment involves normalising screening by offering a chlamydia screen to all 15-24 year olds at every interaction with staff, offering screening with a non-judgemental attitude and minimising barriers to screening such as embarrassment. The GP surgery is the ideal place to screen young people for chlamydia as it is not a threatening place for them and our study has shown that they think it is the normal place to go to discuss health matters.

Poor uptake of self‐sample collection kits for Chlamydia testing outside primary care

New strategies are needed to reach at-risk populations for Chlamydia screening. Self-sample collection kits containing instructions and all items required for testing were developed and piloted in a three-month trial in primary care. Practice staff offered kits to young people receiving opportunistic Chlamydia screening to pass on to their 'social contacts.' The 'pass it on' approach failed to reach adequate numbers of youth for testing: of 67 kits distributed, three specimens were sent to the laboratory (4.5%). The method of kit distribution trialled here was not successful in reaching at-risk youth for testing outside the primary care setting. Use of self-sample collection for chlamydia testing outside healthcare settings is likely to be important for increased access to testing. The importance of chlamydia testing needs to be widely promoted and methods for kit distribution to reach at-risk youth identified.