Francis J. Bowden

Chlamydia trachomatis Incidence and Re-Infection among Young Women – Behavioural and Microbiological Characteristics

Background This study aimed to estimate rates of chlamydia incidence and re-infection and to investigate the dynamics of chlamydia organism load in prevalent, incident and re-infections among young Australian women. Methods 1,116 women aged 16 to 25 years were recruited from primary care clinics in Australia. Vaginal swabs were collected at 3 to 6 month intervals for chlamydia testing. Chlamydia organism load was measured by quantitative PCR. Results There were 47 incident cases of chlamydia diagnosed and 1,056.34 person years of follow up with a rate of 4.4 per 100 person years (95% CI: 3.3, 5.9). Incident infection was associated with being aged 16 to 20 years [RR = 3.7 (95%CI: 1.9, 7.1)], being employed [RR = 2.4 (95%CI: 1.1, 4.9)] and having two or more new sex partners [RR = 5.5 (95%CI: 2.6, 11.7)]. Recent antibiotic use was associated with a reduced incidence [RR:0.1 (95%CI: 0.0, 0.5)]. There were 14 re-infections with a rate of 22.3 per 100 person years (95%CI: 13.2, 37.6). The median time to re-infection was 4.6 months. Organism load was higher for prevalent than incident infections (p<0.01) and for prevalent than re-infections (p<0.01). Conclusions Chlamydia is common among young women and a high proportion of women are re-infected within a short period of time, highlighting the need for effective partner treatment and repeat testing. The difference in organism load between prevalent and incident infections suggests prevalent infection may be more important for ongoing transmission of chlamydia.

Trichomonas vaginalis epidemiology: parameterising and analysing a model of treatment interventions.

Background: Trichomonas vaginalis, which affects at least 170 million individuals globally, may increase the risk of transmission of HIV and predispose pregnant women to premature rupture of membranes and early labour. Objective: To more clearly define the epidemiology of trichomoniasis and to develop a mathematical model of disease transmission dynamics in order to explore various treatment strategies. Design: A deterministic model of trichomoniasis was constructed. Parameter values were set to fit the model to known endemic prevalence levels of Trichomonas vaginalis. Two treatment interventions (“screening” and “syndromic management”) were simulated. Results: The age specific prevalence of the disease was seen to differ from other STDs in a number of studies. Parameter fitting indicates that the average duration of infection in women is at least 3–5 years and approximately 4 months for men. “Syndromic management” (that is, treating only those with symptoms of disease) had minimal effect upon the endemic prevalence of disease even at high levels of coverage. “Screening” (that is, identification of individuals with both symptomatic and asymptomatic infection) was shown to be the most efficient method of control, but was sensitive to the screening interval. Conclusions: The control of trichomoniasis seems to have been a success in developed countries because of the regular access to health care, whereas it has remained endemic in many developing countries where control may only be possible by regular screening and treatment. However, without a large investment in services, success in controlling trichomoniasis is likely to be transitory.

A Self-Administered Technique for the Detection of Sexually Transmitted Diseases in Remote Communities

The control of sexually transmitted diseases (STDs) in remote rural communities would be enhanced by a sensitive self-administered method for the detection of asymptomatic infection. Results of conventional methods for the detection of STDs were compared with results of tampon-collected specimens analyzed by polymerase chain reaction (PCR) for 480 women. Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis were detected by routine methods in 4 (1%), 14 (3%), and 41 (9%) samples, respectively, while PCR detected these organisms from 52 (11%), 26 (5%), and 75 (16%) tampons, respectively. The detection of each organism was significantly greater by PCR in tampon-collected samples than by routine conventional methods (P < .01). Discrepant results were confirmed by separate primers in 40 of 48 specimens for N. gonorrhoeae, in 11 of 12 specimens for C. trachomatis, and in 31 of 32 specimens for T. vaginalis. Tampons tested by PCR provide an acceptable and sensitive method for detection of STDs in women living in remote areas.

Phylogenetic evidence for reclassification of Calymmatobacterium granulomatis as Klebsiella granulomatis comb, nov.

By sequencing a total of 2089 bp of the 16S rRNA and phoE genes it was demonstrated that Calymmatobacterium granulomatis (the causative organism of donovanosis) shows a high level of identity with Klebsiella species pathogenic to humans (Klebsiella pneumoniae, Klebsiella rhinoscleromatis). It is proposed that C. granulomatis should be reclassified as Klebsiella granulomatis comb. nov. An emended description of the genus Klebsiella is given.

The prevalence of genital Chlamydia trachomatis in Australia 1997-2004: a systematic review.

OBJECTIVES To determine by systematic review the prevalence of genital chlamydial infection in Australia between 1997 and 2004. METHODS Electronic literature databases, reference lists, and conference proceedings were searched and health agencies and jurisdictions were contacted for published and unpublished reports. Studies were eligible if they offered a diagnostic nucleic acid amplification test to consecutive individuals presenting during the study period. As a summary measure of the available data, mean prevalence rates, weighted by sample size and irrespective of participant age, were calculated for the population sub-groups. RESULTS 40 studies of 50 populations and 40,587 individuals met the inclusion criteria, but only one of these was population-based. The use of non-systematic methodologies prevented an assessment of time trends and a statistical comparison of population sub-groups. The mean overall prevalence of genital chlamydial infection was 4.6% (95% CI 4.4-4.8%), reflecting over-sampling of high-risk groups. The mean community-based rates were 7.5% (95% CI 6.4-8.6%) and 8.7% (95% CI 7.9-9.7%) for Indigenous men and women, and 1.5% (95% CI 1.1-1.9%) and 1.4% (95% CI 0.9-2.0%) for non-Indigenous men and women. The overall mean estimates for other groups were 3.3% (95% CI 3.0-3.7%) for female attendees of sexual health and related clinics, 5.6% (95% CI 4.9-6.4%) for adolescents and young adults, 3.3% (95% CI 2.8-3.9%) for sex workers, and 1.6% (95% CI 1.2-2.0%) for urethral infection in men who have sex with men. Clinic-based estimates were generally, although not consistently, higher than community-based estimates. There is no serial population-based data for sexually active young men and women, but the available age-specific rates suggest under-ascertainment by the routine surveillance systems. CONCLUSIONS The prevalence of genital chlamydial infection in Indigenous Australians and young adults is unacceptably high and quality epidemiological studies are urgently required to supplement the routinely collected national notification data.

Comparison of tampon and urine as self-administered methods of specimen collection in the detection of Chlamydia trachomatis , Neisseria gonorrhoeae and Trichomonas vaginalis in women

1 Department of Microbiology, The Royal Womens Hospital, Victoria, 2 Menzies School of Health Research, Rocklands Drive, Tiwi, 3 Department of Epidemiology and Preventive Medicine, Alfred Hospital, Monash University, Prahran, Victoria and 4 AIDS/STD Unit, Centre for Disease Control, Territory Health Services, Darwin, Australia Summary: Self-administered sampling techniques for the detection of sexually transmitted diseases (STDs) are particularly useful due to their ease of collection and better patient compliance. Urine specimens, and recently tampons, have been described as methods of specimen collection for the detection of some STDs in women. In this study, 660 women had both first-void urine (FVU) and tampon specimens analysed by polymerase chain reaction (PCR) for the detection of Chlamydia trachomatis , Neisseria gonorrhoeae and Trichomonas vaginalis . Overall 6.5%, 10.1% and 17.9% of urine samples were positive whereas 7%, 21.2% and 22% of tampon specimens were positive for C. trachomatis , N. gonorrhoeae and T. vaginalis respectively. Tampon-collected specimens tested by PCR were more sensitive than urine specimens for the detection of N. gonorrhoeae and T. vaginalis ( P 0.001) and equally sensitive for the detection of C. trachomatis ( P =0.45). <

Reproductive health, infertility and sexually transmitted infections in indigenous women in a remote community in the Northern Territory.

Objective: To investigate markers of reproductive health in a remote Indigenous community in Northern Australia.

Prevalent and incident bacterial vaginosis are associated with sexual and contraceptive behaviours in young Australian women.

Background To determine prevalence and incidence of bacterial vaginosis (BV) and risk factors in young sexually-active Australian women. Methods 1093 women aged 16–25 years were recruited from primary-care clinics. Participants completed 3-monthly questionnaires and self-collected vaginal smears 6-monthly for 12-months. The primary endpoint was a Nugent Score = 7–10 (BV) and the secondary endpoint was a NS = 4–10 (abnormal flora [AF]). BV and AF prevalence estimates and 95% confidence intervals (95%CI) were derived, and adjusted odds ratios (AOR) calculated to explore epidemiological associations with prevalent BV and AF. Proportional-hazards regression models were used to examine factors associated with incident BV and AF. Results At baseline 129 women had BV [11.8% (95%CI: 9.4–14.2)] and 188 AF (17.2%; 15.1–19.5). Prevalent BV was associated with having a recent female partner [AOR = 2.1; 1.0–4.4] and lack of tertiary-education [AOR = 1.9; 1.2–3.0]; use of an oestrogen-containing contraceptive (OCC) was associated with reduced risk [AOR = 0.6; 0.4–0.9]. Prevalent AF was associated with the same factors, and additionally with >5 male partners (MSP) in 12-months [AOR = 1.8; 1.2–2.5)], and detection of C.trachomatis or M.genitalium [AOR = 2.1; 1.0–4.5]. There were 82 cases of incident BV (9.4%;7.7–11.7/100 person-years) and 129 with incident AF (14.8%; 12.5–17.6/100 person-years). Incident BV and AF were associated with a new MSP [adjusted rate ratio (ARR) = 1.5; 1.1–2.2 and ARR = 1.5; 1.1–2.0], respectively. OCC-use was associated with reduced risk of incident AF [ARR = 0.7; 0.5–1.0]. Conclusion This paper presents BV and AF prevalence and incidence estimates from a large prospective cohort of young Australian women predominantly recruited from primary-care clinics. These data support the concept that sexual activity is strongly associated with the development of BV and AF and that use of an OCC is associated with reduced risk.

Experiences and outcomes of partner notification among men and women recently diagnosed with chlamydia and their views on innovative resources aimed at improving notification rates.

Objective: To describe the partner notification experiences of individuals diagnosed with chlamydia and to determine what supports might best assist them. Goal: To determine what supports might best assist chlamydia infected individuals to notify their partners. Study Design: A telephone survey was undertaken with men and women recently diagnosed with chlamydia across 3 Australian jurisdictions between August 2007 and January 2008. Results: Of the 286 individuals who agreed to be contacted about the study, 202 (71%) completed the survey. Twenty-three percent (333/1458) of recent partners were notified: men who had sex with men (MSM) notified 15% (133/880) of their partners, heterosexual men 31% (114/370), and women 46% (86/188) of their partners (P < 0.001). Overall, 84% (169/202) of individuals notified at least one partner. The main reasons for informing partners were out of concern for them (44%) or because it was considered “the right thing to do” (37%). The preferred methods for contacting partners were telephone (52%) and face-to-face (30%). E-mail (8%) and short message service (SMS) (11%) were less commonly used; however, if offered a website with anonymous e-mail and SMS services, nearly half of individuals indicated they would find this useful. Of those who had not informed all partners with known contact details (n = 94), 34% reported that if web-based tools were available they would have contacted more partners. Over half of participants would like to have been given antibiotics to give to their partner. Conclusion: The availability of tailored resources may assist in improving partner notification for chlamydia.

Pooling of Clinical Specimens Prior to Testing for Chlamydia trachomatis by PCR Is Accurate and Cost Saving

ABSTRACT The accuracy and cost savings of pooling specimens prior to testing for Chlamydia trachomatis by PCR were evaluated with genital and urine specimens (n = 2,600). There was a 60% reduction in tests without significant loss of accuracy. The efficiency of pooling vaginal swabs is demonstrated for the first time.