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Review
. 2016 Sep 13;9(9):CD010866.
doi: 10.1002/14651858.CD010866.pub2.

Screening for genital chlamydia infection

Nicola Low  1 , Shelagh Redmond, Anneli Uusküla, Jan van Bergen, Helen Ward, Berit Andersen, Hannelore Götz
Affiliations
Review

Screening for genital chlamydia infection

Nicola Low et al. Cochrane Database Syst Rev. .

Abstract

Background: Genital infections caused by Chlamydia trachomatis are the most prevalent bacterial sexually transmitted infection worldwide. Screening of sexually active young adults to detect and treat asymptomatic infections might reduce chlamydia transmission and prevent reproductive tract morbidity, particularly pelvic inflammatory disease (PID) in women, which can cause tubal infertility and ectopic pregnancy.

Objectives: To assess the effects and safety of chlamydia screening versus standard care on chlamydia transmission and infection complications in pregnant and non-pregnant women and in men.

Search methods: We searched the Cochrane Sexually Transmitted Infections Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS, CINAHL, DARE, PsycINFO and Web of Science electronic databases up to 14 February 2016, together with World Health Organization International Clinical Trials Registry (ICTRP) and ClinicalTrials.gov. We also handsearched conference proceedings, contacted trial authors and reviewed the reference lists of retrieved studies.

Selection criteria: Randomised controlled trials (RCTs) in adult women (non-pregnant and pregnant) and men comparing a chlamydia screening intervention with usual care and reporting on a primary outcome (C. trachomatis prevalence, PID in women, epididymitis in men or incidence of preterm delivery). We included non-randomised controlled clinical trials if there were no RCTs for a primary outcome.

Data collection and analysis: Two review authors independently assessed trials for inclusion, extracted data and assessed the risk of bias. We resolved disagreements by consensus or adjudication by a third reviewer. We described results in forest plots and conducted meta-analysis where appropriate using a fixed-effect model to estimate risk ratios (RR with 95% confidence intervals, CI) in intervention vs control groups. We conducted a pre-specified sensitivity analysis of the primary outcome, PID incidence, according to the risks of selection and detection bias.

Main results: We included six trials involving 359,078 adult women and men. One trial was at low risk of bias in all six specific domains assessed. Two trials examined the effect of multiple rounds of chlamydia screening on C. trachomatis transmission. A cluster-controlled trial in women and men in the general population in the Netherlands found no change in chlamydia test positivity after three yearly invitations (intervention 4.1% vs control 4.3%, RR 0.96, 95% CI 0.84 to 1.09, 1 trial, 317,304 participants at first screening invitation, low quality evidence). Uptake of the intervention was low (maximum 16%). A cluster-randomised trial in female sex workers in Peru found a reduction in chlamydia prevalence after four years (adjusted RR 0.72, 95% CI 0.54 to 0.98, 1 trial, 4465 participants, low quality evidence).Four RCTs examined the effect of chlamydia screening on PID in women 12 months after a single screening offer. In analysis of four trials according to the intention-to-treat principle, the risk of PID was lower in women in intervention than control groups, with little evidence of between-trial heterogeneity (RR 0.68, 95% CI 0.49 to 0.94, I2 7%, 4 trials, 21,686 participants, moderate quality evidence). In a sensitivity analysis, the estimated effect of chlamydia screening in two RCTs at low risk of detection bias (RR 0.80, 95% CI 0.55 to 1.17) was compatible with no effect and was lower than in two RCTs at high or unclear risk of detection bias (RR 0.42, 95% CI 0.22 to 0.83).The risk of epididymitis in men invited for screening, 12 months after a single screening offer, was 20% lower risk for epididymitis than in those not invited; the confidence interval was wide and compatible with no effect (RR 0.80, 95% CI 0.45 to 1.42, 1 trial, 14,980 participants, very low quality evidence).We found no RCTs of the effects of chlamydia screening in pregnancy and no trials that measured the harms of chlamydia screening.

Authors' conclusions: Evidence about the effects of screening on C. trachomatis transmission is of low quality because of directness and risk of bias. There is moderate quality evidence that detection and treatment of chlamydia infection can reduce the risk of PID in women at individual level. There is an absence of RCT evidence about the effects of chlamydia screening in pregnancy.Future RCTs of chlamydia screening interventions should determine the effects of chlamydia screening in pregnancy, of repeated rounds of screening on the incidence of chlamydia-associated PID and chlamydia reinfection in general and high risk populations.

PubMed Disclaimer

Conflict of interest statement

Berit Andersen is coauthor of two completed trials that are included in the review.

Jan van Bergen, Hannelore Götz and Nicola Low are coauthors on a completed trial that is included in the review .

Authors of included studies will not be involved in assessing and extracting data of their own studies.

Figures

1
1
#Study flow diagram.
2
2
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
3
3
Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
4
4
Forest plot of comparison: 1 Offer of chlamydia screening vs usual care (inactive control), outcome: 1.2 Incidence of PID at 12 months (intention‐to‐treat).
1.1
1.1. Analysis
Comparison 1 Offer of chlamydia screening vs usual care (inactive control), Outcome 1 Prevalence of chlamydia infection (positivity) measured in the whole study population at least 12 months after start of screening.
1.2
1.2. Analysis
Comparison 1 Offer of chlamydia screening vs usual care (inactive control), Outcome 2 Incidence of PID at 12 months (intention‐to‐treat).
1.3
1.3. Analysis
Comparison 1 Offer of chlamydia screening vs usual care (inactive control), Outcome 3 Incidence of PID at 12 months (per protocol analysis).
1.4
1.4. Analysis
Comparison 1 Offer of chlamydia screening vs usual care (inactive control), Outcome 4 Incidence of epididymitis in men at 12 months (intention to screen).
1.5
1.5. Analysis
Comparison 1 Offer of chlamydia screening vs usual care (inactive control), Outcome 5 Secondary outcomes for reproductive tract morbidity.
See this image and copyright information in PMC

Update of

References

References to studies included in this review

Andersen 2011 {published data only}
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Garcia 2012 {published data only}
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Oakeshott 2010 {published data only}
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    1. Oakeshott P, Kerry S, Aghaizu A, Atherton H, Hay S, Taylor‐Robinson D, et al. Randomised controlled trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial. BMJ 2010;340:c1642. - PMC - PubMed
    1. Oakeshott P, Kerry S, Atherton H, Aghaizu A, Hay S, Taylor‐Robinson D, Simms I, Williams E, Hay P. Community‐based trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (Prevention Of Pelvic Infection) trial. [Abstract P4.77]. ISSTDR/BASHH meeting. 2009 28 June‐1 July; London, UK.
    1. Oakeshott P, Kerry S, Atherton H, Aghaizu A, Hay S, Taylor‐Robinson D, et al. Community‐based trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: The POPI (prevention of pelvic infection) trial. Trials 2008;9:15. - PMC - PubMed
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Scholes 1996 {published data only}
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van den Broek 2012 {published data only}
    1. Op de Coul EL, Weenen TC, Bergen JEAM, Brouwers EEHG, Feijter EM, Fennema JSA, Gotz HM, Hoebe CJPA, Koekenbier RH, Ravensteijn SM, Broek IVF. Process evaluation of the chlamydia screening implementation Netherlands: results from the first operational phase. [Abstract P4.68]. ISSTDR/BASHH meeting. 2009 28 June‐1 July; London, UK.
    1. Bergen JEAM, Fennema JSA, Broek IVF, Brouwers EEHG, Feijter EM, Hoebe CJPA, Koekenbier RH, Op de Coul ELM, Ravensteijn SM, Gotz HM. Development and implementation of a systematic selective internet‐based chlamydia screening program, the Netherlands 2008‐2010: rationale and design. [Abstract P4.42]. ISSTDR/BASHH meeting. 2009 28 June‐1 July; London, UK.
    1. Broek IVF, Hoebe CJPA, Bergen JEAM, Brouwers EEHG, Feijter EM, Fennema JSA, et al. Evaluation design of a systematic, selective, internet‐based, chlamydia screening implementation in the Netherlands,2008‐2010: implications of first results for the analysis. BMC Infectious Diseases 2010;10:89. - PMC - PubMed
    1. Broek IVF, Hoebe CJPA, Bergen JEAM, Brouwers EEHG, Feijter EM, Fennema JSA, Gotz HM, Koekenbier RH, Ravensteijn SM, Op de Coul EL. First phase of the stepwise chlamydia screening implementation in the Netherlands: participation rates and implications for measures of effect. [Abstract P4.67]. ISSTDR/BASHH meeting. 2009 28 June‐1 July; London, UK.
    1. Broek IVF, Bergen JEAM, Brouwers EEHG, Fennema JSA, Gotz HM, Hoebe CJPA, et al. Effectiveness of yearly, register based screening for chlamydia in the Netherlands: controlled trial with randomised stepped wedge implementation. BMJ 2012;345:7869. - PMC - PubMed

References to studies excluded from this review

ACTRN12608000499381 {published data only}
    1. ACTRN12608000499381. Chlamydia prevalence and testing program targetting women aged 16 to 24 years in general practice. http://www.anzctr.org.au/ACTRN12608000499381.aspx (accessed 9 June 2016).
Andrews 2006 {published data only}
    1. Andrews WW, Klebanoff MA, Thom EA, Hauth JC, Carey JC, Meis PJ, et al. Midpregnancy genitourinary tract infection with Chlamydia trachomatis: association with subsequent preterm delivery in women with bacterial vaginosis and Trichomonas vaginalis. American Journal of Obstetric Gynecology 2006;194(2):493‐500. - PubMed
Bailey 2013 {published data only}
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Banhidy 2011 {published data only}
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Bowden 2008 {published data only}
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Brown 2010 {published data only}
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Cabeza 2015 {published data only}
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    1. Cabeza J, Garcia PJ, Segura E, García P, Escudero F, Rosa S, et al. Feasibility of Chlamydia trachomatis screening and treatment in pregnant women in Lima, Peru: a prospective study in two large urban hospitals. Sexually Transmitted Infections 2015;91(1):7‐10. - PMC - PubMed
Chandeying 1998 {published data only}
    1. Chandeying V, Skov S, Kemapunmanus M, Law M, Geater A, Rowe P. Evaluation of two clinical protocols for the management of women with vaginal discharge in southern Thailand. Sexually Transmitted Infections 1998;74(3):194‐201. - PMC - PubMed
Cohen 1999 {published data only}
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Cook 2007 {published data only}
    1. Cook RL, Ostergaard L, Hillier SL, Murray PJ, Chang CCH, Comer DM, et al. Home screening for sexually transmitted diseases in high‐risk young women: randomised controlled trial. Sexually Transmitted Infections 2007;83(4):286‐91. - PMC - PubMed
    1. NCT00177437. Home screening for chlamydia surveillance. http://clinicaltrials.gov/show/NCT00177437 (accessed 9 June 2016).
De Barbeyrac 2013 {published data only}
    1. Barbeyrac B, Rahib D, Diego S, Roy C, Bébéar C, Lydie N. Internet testing for Chlamydia trachomatis in France in 2012 [P3.025]. Sexually Transmitted Infections 2013;89(Suppl 1):A155‐A156.
Downing 2013 {published data only}
    1. Downing SG, Cashman C, McNamee H, Penney D, Russell DB, Hellard ME. Increasing chlamydia test of re‐infection rates using SMS reminders and incentives. Sexually Transmitted Infections 2013;89(1):16‐9. - PubMed
Gotz 2013 {published data only}
    1. Gotz HM, Wolfers MEG, Luijendijk A, Broek IVF. Retesting for genital Chlamydia trachomatis among visitors of a sexually transmitted infections clinic: randomized intervention trial of home‐ versus clinic‐based recall. BMC Infectious Diseases 2013;13(1):16. - PMC - PubMed
Graseck 2010 {published data only}
    1. *Graseck A, Secura G, Allsworth J, Madden T, Peipert J. Randomized trial of home vs. clinic‐based screening for sexually transmitted infections in long‐acting reversible Contraceptive users. Contraception 2010;82(2):187.
    1. Graseck AS, Secura GM, Allsworth JE, Madden T, Peipert JF. Home compared with clinic‐based screening for sexually transmitted infections: a randomized controlled trial. Obstetrics and Gynecology 2010;116(6):1311‐8. - PMC - PubMed
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Guy 2013 {published data only}
    1. ACTRN12613000808741. A randomised trial to evaluate whether point‐of‐care testing for chlamydia and gonorrhoea in remote Aboriginal communities can reduce repeat positivity at three months after treatment, among people with chlamydia or gonorrhoea infection. http://www.anzctr.org.au/ACTRN12613000808741.aspx (accessed 9 June 2016).
    1. Guy RJ. Point‐of‐care tests for Chlamydia and Gonorrhoea infections in remote Aboriginal communities: the Test, Treat and Go‐ The 'TTANGO' Trial. [Paper Ref 1065]. IUSTI Meeting. 2012 15‐17 October; Melbourne, Australia. - PMC - PubMed
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Hodgins 2002 {published data only}
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ISRCTN16261241 {published data only}
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ISRCTN38526137 {published data only}
    1. ISRCTN38526137. A randomised controlled study of mouth swab testing versus same‐day blood tests for human immunodeficiency virus (HIV) infection in young people attending a young person's community drug service. http://isrctn.org/ISRCTN38526137 (accessed 9 June 2016). - PubMed
Jones 2007 {published data only}
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Kersaudy‐Rahib 2013 {published data only}
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Kiss 2004 {published data only}
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Klovstad 2013 {published data only}
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Lawton 2010 {published data only}
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Martin 1997 {published data only}
    1. Martin DH, Eschenbach DA, Cotch MF, Nugent RP, Rao AV, Klebanoff MA, et al. Double‐blind placebo‐controlled treatment trial of Chlamydia trachomatis endocervical infections in pregnant women. Infectious Diseases in Obstetrics and Gynecology 1997;5(1):10‐7. - PMC - PubMed
McGregor 1990 {published data only}
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Meyer 1991 {published data only}
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NCT00829517 {published data only}
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NCT01654991 {published data only}
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Niza 2014 {published data only}
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Scholes 2006 {published data only}
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Scholes 2007 {published data only}
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Senok 2005 {published data only}
    1. Senok A, Wilson P, Reid M, Scoular A, Craig N, McConnachie A, et al. Can we evaluate population screening strategies in UK general practice? A pilot randomised controlled trial comparing postal and opportunistic screening for genital chlamydial infection. Journal of Epidemiology and Community Health. 2005;59(3):198‐204. - PMC - PubMed
Shafer 2002 {published data only}
    1. Shafer MA, Tebb KP, Pantell RH, Wibbelsman CJ, Neuhaus JM, Tipton AC, et al. Effect of a clinical practice improvement intervention on chlamydial screening among adolescent girls. JAMA: the journal of the American Medical Association 2002;288(22):2846‐52. - PubMed
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Smith 2014 {published data only}
    1. ACTRN12611000968976. Randomised controlled trial (RCT) of self‐collection samples to increase chlamydia re‐testing following a chlamydia diagnosis amongst clients attending two urban sexual health clinics. http://www.anzctr.org.au/ACTRN12611000968976.aspx (accessed 9 June 2016).
    1. Smith KS, Hocking J, Wand H. Home‐based sample collection increases chlamydia retesting and detects additional repeat positive tests: a randomised controlled trial in three risk groups. [Abstract O22.7]. Sexually Transmitted Infections 2013;89(Suppl 1):A1–A428.
    1. Smith KS, Hocking JS, Chen M, Fairley CK, McNulty A, Read P, et al. Rationale and design of REACT: a randomised controlled trial assessing the effectiveness of home‐collection to increase chlamydia retesting and detect repeat positive tests. BMC Infectious Diseases 2014;14:223. - PMC - PubMed
Stevens‐Simon 2002 {published data only}
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Tebb 2005 {published data only}
    1. Tebb KP, Pantell RH, Wibbelsman CJ, Neuhaus JM, Tipton AC, Pecson SC, et al. Screening sexually active adolescents for Chlamydia trachomatis: what about the boys?. American Journal of Public Health 2005;95(10):1806‐10. - PMC - PubMed
Tebb 2009 {published data only}
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Walker 2010 {published data only}
    1. ACTRN12605000411640. A computer alert to increase chlamydia testing of high risk women in general practice: a cluster randomised controlled trial. http://www.anzctr.org.au/ACTRN12605000411640.aspx (accessed 9June 2016).
    1. Walker J, Fairley CK, Walker SM, Gurrin LC, Gunn JM, Pirotta MV, et al. Computer reminders for chlamydia screening in general practice: a randomized controlled trial. Sexually Transmitted Diseases 2010;37(7):445‐50. - PubMed
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Xu 2011 {published data only}
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References to ongoing studies

Hocking 2010 {published data only}
    1. ACTRN12610000297022. Australian Chlamydia Control Effectiveness Pilot: a trial to determine whether annual chlamydia testing in general practice can lead to a reduction in chlamydia prevalence.. http://www.anzctr.org.au/ACTRN12610000297022.aspx (accessed 9 June 2016).
    1. Hocking J. The Australian Chlamydia Control Effectiveness Pilot (ACCEPt): early results from a randomised trial of annual chlamydia screening in general practice. [Abstract P5.017]. Sexually Transmitted Infections. 2013; Vol. 89, issue Suppl 1:A339‐A340.
    1. Hocking J, Poznanski S, Vaisey A, Walker J, Wood A, Lewis D, et al. A multifaceted intervention to increase chlamydia testing in Australian general practice. Sexually Transmitted Infections 2011;87(Suppl 1):A199.
    1. Hocking J, Spark S, Guy R, Temple‐Smith M, Fairley C, Kaldor J, et al. The Australian Chlamydia Control Effectiveness Pilot (ACCEPT): first results from a randomised trial of annual chlamydia screening in general practice. Sexually Transmitted Infections 2012;88(Suppl 1):A3‐4.
    1. Hocking J, Temple‐Smith M, Poznanski S, Guy R, Low N, Donovan B, et al. Australian chlamydia control effectiveness pilot: preliminary results from a trial of chlamydia testing in general practice. Sexually Transmitted Infections 2011;87(Suppl 1):A202.
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