Prevalence of Chlamydia trachomatis in young men in north west London

Prevalence of genital Chlamydia trachomatis infection in the general population: a meta-analysis

Background

Estimating prevalence of Chlamydia trachomatis (CT) worldwide is necessary in designing control programs and allocating health resources. We performed a meta-analysis to calculate the prevalence of CT in the general population.

Methods

The Pubmed and Embase databases were searched for eligible population-based studies from its inception through June 5, 2019. Q test and I² statistic were used to calculate the heterogeneity between studies. Random effects models were used to pool the prevalence of CT. Meta regression was performed to explore the possible sources of heterogeneity. Publication bias was evaluated using a funnel plot and “trim and fill” method.

Results

Twenty nine studies that reported prevalence of CT infection from 24 countries were identified, including a total population of 89,886 persons. The pooled prevalence of CT among the general population was 2.9% (95% CI, 2.4–3.5%), and females had a higher CT prevalence (3.1, 95% CI, 2.5–3.8%) than males (2.6, 95% CI, 2.0–3.2%) (χ² = 10.38, P <  0.01). Prevalence of CT was highest in region of America (4.5, 95% CI, 3.1–5.9%), especially in Latin America (6.7, 95% CI, 5.0–8.4%), followed by females in region of Africa (3.8, 95% CI, 0.7–6.9%), while South-East Asia had a lowest CT prevalence 0.8% (95% CI, 0.3–1.3%).

Conclusions

This study provided the updated prevalence of CT among general population worldwide. General population from Latin America, especially females, and women in Africa should be given priority by WHO when design and delivery CT control programs.

[Prevalence of Chlamydia trachomatis infection and factors with the risk of acquiring sexually transmitted infections in college students]

Chlamydia trachomatis genital infection is nowadays considered one of the most frequent causes of sexually transmitted infections (STI) in the world, mainly affecting the group of young people under 25 years old. The aim of this study was to determine the prevalence of C. trachomatis infection in newly admitted students to Universidad Nacional del Sur, Bahía Blanca, Argentina, and to evaluate the risk factors to acquire STI. For that purpose, 204 young college students with a mean age of 19 were involved in this study. Each participant delivered a sample of first-void urine and completed a questionnaire which was then submitted anonymously. The research for C. trachomatis was done on 114 valid samples through a technique of DNA amplification, whose molecular target was the gene ompA. Four cases of infection by C. trachomatis were detected with a prevalence of 3.5%. The risks factors associated to the infection were a history of 7 or more partners since the start of sexual activity and contact with a new sexual partner in the last 4 months. The prevalence of such infection reflects a moderate circulation of this microorganism in the studied population. This fact, along with some aspects shown by the questionnaire results, would characterize a population having a low risk profile for acquiring STIs. However, some other information obtained from the questionnaires gave some opposite evidence, which would alert us on the need of keeping watch, raising awareness and implementing preventive actions in this population.

Genital chlamydia prevalence in Europe and non-European high income countries: systematic review and meta-analysis

Background

Accurate information about the prevalence of Chlamydia trachomatis is needed to assess national prevention and control measures.

Methods

We systematically reviewed population-based cross-sectional studies that estimated chlamydia prevalence in European Union/European Economic Area (EU/EEA) Member States and non-European high income countries from January 1990 to August 2012. We examined results in forest plots, explored heterogeneity using the I² statistic, and conducted random effects meta-analysis if appropriate. Meta-regression was used to examine the relationship between study characteristics and chlamydia prevalence estimates.

Results

We included 25 population-based studies from 11 EU/EEA countries and 14 studies from five other high income countries. Four EU/EEA Member States reported on nationally representative surveys of sexually experienced adults aged 18–26 years (response rates 52–71%). In women, chlamydia point prevalence estimates ranged from 3.0–5.3%; the pooled average of these estimates was 3.6% (95% CI 2.4, 4.8, I² 0%). In men, estimates ranged from 2.4–7.3% (pooled average 3.5%; 95% CI 1.9, 5.2, I² 27%). Estimates in EU/EEA Member States were statistically consistent with those in other high income countries (I² 0% for women, 6% for men). There was statistical evidence of an association between survey response rate and estimated chlamydia prevalence; estimates were higher in surveys with lower response rates, (p = 0.003 in women, 0.018 in men).

Conclusions

Population-based surveys that estimate chlamydia prevalence are at risk of participation bias owing to low response rates. Estimates obtained in nationally representative samples of the general population of EU/EEA Member States are similar to estimates from other high income countries.

Chlamydia trachomatis infection and sexual behaviour among female students attending higher education in the Republic of Ireland

Background

There are no prevalence data on Chlamydia trachomatis relating to female students attending higher education available for the Republic of Ireland. This information is required to guide on the necessity for Chlamydia screening programmes in higher education settings. This research aimed to determine the prevalence of and predictive risk factors for Chlamydia trachomatis genital infection among female higher education students in Ireland.

Methods

All females presenting during one-day periods at Student Health Units in three higher education institutions in two cities in the Republic of Ireland were invited to participate. Participants completed a questionnaire on lifestyle and socio-demographic factors and provided a urine sample. Samples were tested for C. trachomatis DNA by a PCR based technique (Cobas Amplicor, Roche). To examine possible associations between a positive test and demographic and lifestyle risk factors, a univariate analysis was performed. All associations with a p value < 0.05 were included in a multivariate logistic regression analysis.

Results

Of the 460 sexually active participants 22 tested positive (prevalence 4.8%; 95% CI 3.0 to 7.1%). Variables associated with significantly increased risk were current suggestive symptoms, two or more one-night stands and three or more lifetime sexual partners. The students displayed high-risk sexual behaviour.

Conclusion

The prevalence of C. trachomatis infection and the lack of awareness of the significance of suggestive symptoms among sexually experienced female students demonstrate the need for a programme to test asymptomatic or non-presenting higher education students. The risk factors identified by multivariate analysis may be useful in identifying those who are most likely to benefit from screening. Alcohol abuse, condom use, sexual behaviour (at home and abroad) and, knowledge of sexually transmitted infections (STIs) (including asymptomatic nature or relevant symptoms) were identified as target areas for health promotion strategies. These strategies are needed in view of the high-risk sexual activity identified.

Opportunistic screening for Chlamydia trachomatis in men attending three different secondary healthcare settings

OBJECTIVES

To assess the feasibility and acceptability of opportunistic Chlamydia trachomatis (CT) screening of asymptomatic men attending three different secondary healthcare settings and to investigate CT positivity in these settings.

METHODS

Men attending fracture, fertility and family planning (FP) clinics were invited to be screened by first-void urine and complete a questionnaire which collected demographic, sexual and behavioural characteristics, and their opinion about the screening process.

RESULTS

1290 men were approached, with 80% participating. The number of men approached, number providing a satisfactory urine specimen and CT positivity rate (95% CI) were, respectively, n = 401, n = 206, 14.6% (10.4 to 20.1) for the FP clinic, n = 505, n = 328, 1.2% (0.5 to 3.2) for the fracture clinic and n = 384, n = 319, 0.3% (0.1 to 1.8) for the fertility clinic. The highest rates of CT infection were found in men attending the FP clinics, aged between 20-24 years. Most of the men from all three clinics felt that the setting (87.9%) and specimen (97.7%) were acceptable.

CONCLUSION

Opportunistic chlamydial screening of asymptomatic men in three secondary healthcare settings found high positivity rates, but low uptake rates in a FP setting compared with fertility and fracture clinics. Innovative and targeted intervention strategies are required to engage this high-risk group of men in screening.

Diagnóstico de la infección por Chlamydia trachomatis en un centro de diagnóstico y prevención de infecciones de transmisión sexual: evaluación de los exudados cervicales, uretrales y rectales mediante técnica de PCR

INTRODUCTION

The aim of this study is to analyze the clinical and epidemiological characteristics of Chlamydia trachomatis infection in patients attended in a clinic for sexually transmitted disease in Seville (Spain). Microbiological diagnosis was performed in various types of samples.

MATERIAL AND METHODS

The study included 3854 patients (50.8% women and 49.2% men, mean age 30.1 years) seen from 2002 to 2004. Among the total, 50% belonged to groups engaging in high risk sexual practices: female commercial sex workers (CSWs) (47%), men who maintain sexual relationships with other men (MSM) (45%), users of prostitution (4%), promiscuous heterosexual men (4%), those with a risk partner (2.7%) and injection drug users (IDU) (2.2%). We analyzed a total of 5978 samples (2384 cervical exudates, 2645 urethral exudates and 949 rectal exudates), for the detection of C. trachomatis by PCR technique with the COBAS Amplicor CT System.

RESULTS

Prevalence of C. trachomatis infection was 6% (4.3% in women and 7.8% in men). Among the total in women, 51.2% of positive samples were from women with high-risk sex factors and 73.8% of the women were asymptomatic. In men, the proportions were 70.5% and 36.9%, respectively. Cervical, urethral and rectal exudates yielded positive results in 4%, 4.9% and 4.3%, respectively.

CONCLUSIONS

Systematic sampling for C. trachomatis detection is necessary in symptomatic and asymptomatic patients practicing high-risk sex; periodic follow-up studies are also needed for early detection of sexually transmitted infection. Rectal sample collection is important for detecting this infection in MSM and in patients whose sexual habits make it advisable.

Are volunteers delivering semen samples in fertility studies a biased population?

BACKGROUND

It is not known to what extent the results of epidemiological studies on male fertility and semen quality based on voluntary participation in the general population are relevant.

METHODS

In a study on the reproductive health of male partners of pregnant women, information was obtained from a group of men agreeing to collect a semen sample and to complete a questionnaire (group A), a group only completing the questionnaire (group B) and from men refusing to participate altogether (group C).

RESULTS

The participation rate (group A) was 15.8% for 1409 men approached. Ages and socio-professional status were similar in the three groups. Time to pregnancy (TTP) was not significantly different in groups A and B, although there appeared to be an insignificantly higher proportion of couples taking longer than 12 months to conceive in group A than in group B. A history of urogenital disease appeared to be more frequent in groups A and B than in the general population. However, comparable semen characteristics were found for men with or without a history of urogenital disease. Pregnancy outcomes were similar in the three groups.

CONCLUSIONS

The present study does not suggest major selection bias, although the social and reproductive histories of these men may prompt them to participate. Such factors need to be accounted for in similar studies.

Chlamydia trachomatis in the United Kingdom: a systematic review and analysis of prevalence studies

OBJECTIVES

To undertake a systematic review to obtain estimates of genital Chlamydia trachomatis prevalence in various populations in the United Kingdom and Ireland; to determine which populations have the highest rates of infection; and to explore the most important determinants of infection.

METHODS

Electronic databases were searched using the keywords "chlamydia" and "England," "Wales," "UK," "Scotland," "Ireland," or "Britain." Additional unpublished data and references were solicited from experts. Studies were included in the analysis if C trachomatis prevalence was reported, and if they met inclusion criteria. Nine variables identified as potentially important descriptors of chlamydia prevalence were extracted from each study and analysed using various logistic regression models. Only studies reporting prevalence in female populations were included in the models, because there were few data from males.

RESULTS

357 studies were identified using the search methods, 90 of which met inclusion criteria, and 19 of which contributed to the final model. The most influential variables on prevalence were age and setting of the population tested. In general practice surgeries, the under 20 year old age group had an estimated prevalence of 8.1% (95% CI 6.5 to 9.9), 20-24 year olds 5.2% (95% CI 4.3 to 6.3), 25-29 year olds 2.6% (95% CI 2.0 to 3.3), decreasing to 1.4% (95% CI 1.0 to 1.9) in those aged over 30 years. Overall, healthcare settings had higher prevalence estimates than population based studies. For example, among under 20 year olds, estimates were 17.3% (95% CI 13.6 to 21.8) in genitourinary medicine clinics, 12.6% (95% CI 6.4 to 23.2) in antenatal clinics, 12.3% (95% CI 9.8 to 15.3) in termination of pregnancy clinics, 10.7% (95% CI 8.3 to 13.8) in youth clinics, 10.0% (95% CI 8.7 to 11.5) in family planning clinics, and 8.1% (95% CI 6.5 to 9.9) in general practice, compared to 5.0% (95% CI 3.2 to 7.6) in population based studies. The type of test, specimen used, date, and location of test were not strongly associated with chlamydia prevalence.

CONCLUSION

The chlamydia prevalence estimates by age and setting from the model may be used to inform chlamydia screening strategies. The systematic review revealed much heterogeneity in the studies identified, but with clear patterns of prevalence. It also indicated gaps in the knowledge about chlamydia prevalence in certain subgroups such as men and the general population.

Chlamydia trachomatis prevalence in men in the mid-west of Ireland

OBJECTIVES

To estimate the prevalence of chlamydia infection in young men in the Mid-Western Health Board Region of Ireland, and to determine risk factors for its acquisition.

METHODS

Consecutive men attending orthopaedic clinics (OPD), and a university sports arena (UL) were recruited to a chlamydia prevalence study. All men aged 17-35 who had been sexually active and had not passed urine in the last hour were eligible. Information about chlamydia was given, informed consent obtained, and a self administered questionnaire was completed. A first void urine (FVU) was collected and tested by ligase chain reaction (LCR).

RESULTS

82% (207/252) of men from OPD, and 60% (186/310) from UL participated. 6.3% (13/207) from the OPD and 5.4% (10/186) from UL tested LCR positive, giving an overall prevalence of 5.9% (23/393). Proved risk factors for chlamydial positivity were: (1) more than one sexual partner in previous 6 months, (2) more than eight lifetime sexual partners, (3) current symptoms (dysuria or discharge). No statistical significance was found for age, condom use, smoking, days since last sexual intercourse and previous GUM clinic attendance. No statistically significant difference to cost effective prevalence of 6% was shown.

CONCLUSIONS

A 5.9% prevalence of Chlamydia trachomatis was found which is cost effective to screen and treat. Non-invasive screening of men in the community was possible. Numbers of sexual partners and current symptoms were significant risk factors. Since only 25% of men in this laboratory were diagnosed with chlamydia outside the GUM clinic, compared with 59% of women, it is important that community screening of men is promoted.

Genital Chlamydia trachomatis infection in a subgroup of young men in the UK

The frequency of genital Chlamydia trachomatis infection in young men in the UK has been found to be consistently lower than that in young women, but studies in such populations might have been affected by selection bias. We tested 798 male military recruits for chlamydia as part of their routine medical examination at Glencorse barracks in Scotland. 78 (9.8%) men were infected with chlamydia; rates of infection were similar in all age-groups. 69 (88%) chlamydia-positive men were asymptomatic. This rate is higher than those usually cited, showing the importance of opportunistic testing for chlamydia in men as well as in women.

Population-based study of chlamydial infection in China: a hidden epidemic

CONTEXT

Sexually transmitted diseases are increasing rapidly in China. Surveillance data imperfectly indicate current prevalence and risk factors.

OBJECTIVES

To estimate the prevalence of genital chlamydial and gonococcal infections and to describe patterns of infection by subgroup and behavioral patterns.

DESIGN, SETTING, AND PARTICIPANTS

A national stratified probability sample of 3426 Chinese individuals (1738 women and 1688 men) aged 20 to 64 years, who were interviewed between August 1999 and August 2000, completed a computer-administered survey, and provided a urine specimen (69% total participation rate).

MAIN OUTCOME MEASURE

Positive test result for chlamydial or gonococcal infections.

RESULTS

The overall prevalence per 100 population of chlamydial infection was 2.6 (95% confidence interval [CI], 1.6-4.1) for women and 2.1 (95% CI, 1.3-3.3) for men. For gonococcal infection, the overall prevalence per 100 population was 0.08 (95% CI, 0.02-0.4) for women and 0.02 (95% CI, 0.005-0.1) for men. Risk factors for chlamydial infection among men aged 20 to 44 years were unprotected sex with a commercial sex worker (odds ratio [OR], 8.24; 95% CI, 3.51-19.35), less education (OR, 7.20; 95% CI, 2.31-22.37), and recent sex with their spouse or other steady partner (OR, 7.73; 95% CI, 2.70-22.10). Among women aged 20 to 44 years, risk factors for chlamydial infection were having less education (OR, 2.82; 95% CI, 1.01-7.91) and living in a city (OR, 3.46; 95% CI, 1.67-7.18) or along the southern coast (OR, 2.16; 95% CI, 1.29-3.63) and having a spouse or other steady sexual partner who earned a high income (OR, 2.85; 95% CI, 1.11-7.29), who socialized often (OR, 2.79; 95% CI, 1.08-7.19), or who traveled less than 1 week per year (OR, 5.40; 95% CI, 1.44-20.3).

CONCLUSIONS

The prevalence of chlamydial infection in China is substantial. The patterns of infection suggest potential avenues for intervention.

Provider willingness to screen all sexually active adolescents for chlamydia

OBJECTIVES

To assess differences in provider willingness to screen all sexually active male and female adolescents for chlamydia and to determine whether concerns about cost effectiveness of screening are related to provider willingness to screen for chlamydia.

METHODS

All primary care providers in a managed care organisation self administered a survey about screening all sexually active adolescents for chlamydia.

RESULTS

Respondents were 217 physicians (MDs) and 121 nurse practitioners (NPs) or physician assistants (PAs). Excluding obstetrician/gynaecologists, more providers were willing to routinely screen adolescent females than males for chlamydia (67% v 49% respectively; p<0.001). Independent predictors of provider willingness to screen both males and females included belief that routine screening is cost effective and being a NP/PA v an MD. Belief that chlamydia screening is easier in females than males independently predicted less willingness to screen males.

CONCLUSION

Information that reduces provider concern about the cost effectiveness of screening may increase provider willingness to screen adolescents for chlamydia. Availability of urine based tests may reduce provider beliefs that females are easier to screen than males and increase chlamydia screening in males.

Chlamydia screening in primary care: is it useful, affordable and universal?

Genital chlamydial infection, with its possible long-term morbidity, is a serious public health problem. The number of new diagnoses is rising rapidly and, in the UK, recent evidence suggests that the infection rate in young women exceeds 10%. Screening programmes can reduce the population prevalence of infection, but uncertainty remains as to the ideal screening model. This may prove to be opportunistic screening of sexually active young women, less than 25 years of age, in primary care settings, and contact tracing of the partners of those with chlamydia. Recent literature on the practicalities of genital chlamydia screening is reviewed.