bluuebunny/crossref_metadata_2025 huggingface dataset:
P1-S4.22 Impact of a hypothetical chlamydia vaccine on population prevalence: a mathematical Modelling Study
Authors: Heijne J , Althaus C , Herzog S , Low N
Published: July 2011

Background

It has not yet been possible to develop aChlamydia trachomatis(chlamydia) vaccine but research to achieve this continues. It is therefore important to evaluate the potential impact of different chlamydia vaccine strategies on population prevalence. The optimal strategy might differ depending on whether a vaccine prevents chlamydia infection, or prevents ascending infection to reduce the risk of long term complications. Here, we used a mathematical model to focus on vaccination strategies that aim to reduce population prevalence.

Methods

We developed a deterministic pair model of heterosexuals aged 15–39 years that incorporates the formation and dissolution of sexual partnerships. We used sexual behavioural data from UK population-based studies to inform the model. The model has a baseline chlamydia prevalence of 3%. In all strategies examined, vaccination was introduced before sexual debut. We investigated the impact on population prevalence of different types of vaccine coverage, vaccine efficacy and duration of protection. We also assumed different types of protection after vaccination. We started with full protection, but since animal models have shown that sterilising immunity is difficult to achieve we also investigated partial protection of the vaccine by assuming a decreased susceptibility to infection after vaccination or, when infected, a shorter duration of infection or a reduced transmission probability.

Results

The impact of different vaccination strategies on chlamydia population prevalence depends on the characteristics of the vaccine. In the best case scenario, where the vaccine coverage and efficacy is 100% and duration of protection lifelong, it takes about 7 years to half the prevalence. With an average duration of protection of 10 years, a vaccine coverage or vaccine efficacy of around 70% or higher per year was needed to half the chlamydia prevalence in 10 years. For high vaccine coverage levels, the impact of vaccinating women alone on population prevalence was greater than vaccinating both men and women. The potential impact of a vaccine on chlamydia population prevalence was sensitive to the duration of protection of the vaccine and the vaccine efficacy.

Conclusion

The model suggests that the impact of vaccination strategies on chlamydia prevalence highly depends on characteristics of future vaccines. Current efforts in vaccine development should be accompanied by mathematical models to investigate the optimal strategies.
P2-S9.01 The impact of customs and sexual practices on young Maasai women's ability to negotiate their sexual and reproductive health in relation to HIV and AIDS in Loitokitok, Kenya
Authors: Matogo J N
Published: July 2011

This research investigated the ways in which Maasai culture, as practiced in a rural and relatively isolated area of Kenya, impacted upon the transmission of HIV/AIDS. The author focused her field research on women aged 16–25, and a range of cultural practices contributing to and influenced by gender roles in Maasai society. Local practice has been addressed and recommendations made in relation to the position of the Maasai community in the wider political economy and Kenya's ethnos cape.

The study also investigated strategies the women considered appropriate, practical and effective to cope with these risks. The field study was conducted in the Loitokitok district of Kenya.

Methodology

The research is within a qualitative paradigm. Choice of methodology was mainly based on ethic consideration of research within cultural context of Maasai Indigenous people. Data was generated through use of focus group discussions, semi structured interviews and informal observation methods. An extensive review of the literature was also conducted. The influence of gender based customs and practices are highlighted in a number of scholarly works, Governmental and non-governmental documents with regard to women's vulnerability to Sexually Transmitted Infections (STIs).

The researcher maintained an “insider-outsider” position and a participatory role in order to try to identify the current state of Maasai women's reproductive health at the grass roots level.

Findings

Research findings have found that there is a challenge in young pastoralist women's reproductive health autonomy. Their risk of STIs especially HIV infection is strongly determined by cultural and sexual practices that are gender related.

Existing customs and practices tend to be more repressive to the women's autonomy in sexual health matters as men hold power in most important roles in society.

Conclusions

The study does not call for cultural change or reformation of traditional culture within the Maasai community; rather it appeals for transformation of customs and practices that cause harm on women's reproductive health. Valuable cultural practices and intentions that recognise women and celebrate their womanhood should be encouraged in a way that is not physically or psychologically daunting experience on their wellbeing.

To this end, the understanding and knowledge of the Maasai worldview is critical to the intervention of Maasai women's reproductive health rights. A more cultural approach to Maasai women's reproductive health is suggested to be more effective. In relation to the adoption of STI prevention measures, Maasai culture plays a key role towards identification of preventive measures and strategies.
P3-S1.26 NovelChlamydia trachomatispoint of care rapid test shows disappointingly low clinical sensitivity in urogenital Chlamydia infections in Paramaribo, Suriname
Authors: van der Helm J , Sabajo L , Morré S , Grunberg A , Speksnijder A , de Vries H
Published: July 2011

Background

Affordable and reliable point of care (POC) tests to diagnose urogenital chlamydia infections (POC-Ct) are needed, especially in resource limited settings. WHO has formulated standards that POC tests have to meet. One of those is that the test should be sensitive. Three POC-Ct tests currently on the market all showed poor sensitivity between 12% and 17% in a non-manufacturer sponsored clinical study (van Dommelen 2010). One POC-Ct test evaluated in a manufacturer-sponsored study claims over 80% sensitivity (Mahilum-Tapay 2007). We evaluated the performance of this POC-Ct in two outpatient clinics in Suriname, S.A.

Methods

Between July 2009 and February 2010 963 women were included in a high risk STI clinic (n=181) and a low risk birth control clinic (n=782) in Paramaribo, Suriname. Nurse collected vaginal swabs were obtained for the POC-Ct (Diagnostics for the Real World, LTD, Cambridge, UK) and control NAAT (APTIMA Combo 2, Gen-Probe, San Diego, USA) in a cross-over model. Swabs were processed according to the manufacturers instructions. POC-Ct was compared to NAAT and sensitivity, specificity, positive- and negative predictive value (PPV, NPV) were calculated. Quantitative Ct load was determined with a real-time PCR targeting the cryptic plasmid. Ct load was expressed as inclusion forming units (IFU) based on defined serial dilutions. An independent t-test was used to compare log-transformed Ct loads between true positive and false negative POC-Ct results.

Results

Ct prevalence, determined by NAAT, was 23% at the high risk STI clinic and 9% at the low risk birth control clinic. Four samples were excluded due to discrepancy in POC-Ct result between two lab technicians (n=3) and failure of POC-Ct (n=1). Performance results of POC-Ct compared to NAAT are shown in Abstract P3-S1.26 table 1. Quantitative Ct bacterial load was 65 times higher when POC-Ct detected Ct infection (geometric mean 115 IFU) compared to loads that POC-Ct did not detect (geometric mean 1.8 IFU, p<0.001). Human DNA concentration did not differ between the true positive and false negative POC-Ct results (p=0.904). Sensitivity of POC-Ct in samples with low Ct load was 16%.

Abstract P3-S1.26 Table 1

Performance results of POC-Ct compared to NAAT

NAAT +NAAT −SensitivitySpecificityPPVNPVPOC-Ct +483041.7%97.6%61.5%92.4%POC-Ct −67814

Conclusion

The sensitivity and to a lesser extend the PPV of the POC-Ct did not meet the expectations as described previously (83.5%). The POC-Ct missed samples with a low Ct load. With a sensitivity of 41.7% the Diagnostics of the Real World POC-Ct test does not meet the ASSURED criteria of a sensitive test formulated by the WHO.
P3-S1.35 Systemic and mucosal IgG and IgA antibody responses in genitalChlamydia trachomatisinfection
Authors: Wiggins R , Morris G , Habgood L , Lacey C
Published: July 2011

Background

Chlamydia trachomatis(CT) is the most common sexually transmitted infection in the UK. Screening and treatment programmes do not appear to have reduced the population levels of Chlamydia. Ideally a vaccine stimulating both humoural and T-cell responses against CT should be developed. We therefore wished to further study the humoural immune response to chlamydial infection both systemically and mucosally in the female genital tract in natural infection.

Methods

Cervical secretions (obtained with Weck-Cel spears, Medtronic) and serum from twenty-six women diagnosed chlamydia-positive were assessed for Chlamydia-specific IgA and IgG responses (Anilab systems, Finland) at baseline and at 4 months follow-up. Samples from thirty chlamydia-negative women were used as controls. The Mann–Whitney non-parametric test was used to compare groups.

Results

There was a significant difference between CT+ve and CT−ve IgG in serum samples (IgG median absorbance values p=0.006, median CT-ve samples 0, +ve samples 0.255) and IgA serum values (p=0.005, CT+ve median 0.491, CT−ve 0.119). There was no significant difference between cervical IgG and IgA levels between CT+ve and CT−ve women (IgG median absorbance values, CT+ve samples 0.012, 0 CT−ve; IgA CT−ve 0.202, CT+ve, 0.032), although there was a trend towards raised cervical IgG in CT+ve samples (p=0.08). There was no significant difference between antibody levels at baseline and 4 months for the 10 CT+ve women who have returned so far.

Discussion

Our data suggests that the local and systemic antibody responses to genital chlamydial infection are highly variable. No CT+ve samples studied display positive absorbance levels in all four tested parameters. However, serum IgG and IgA responses are significantly raised in CT+ve individuals, and these values remain high at 4 months follow-up. This is in contrast to local responses which are not significantly different between CT+ve and CT−ve individuals, although there is a trend towards raised cervical IgG in CT+ve samples. The results of this study so far indicate that local immune responses, in comparison to systemic responses, are not well-defined. This may have implications both for chlamydial vaccine development, and mucosal assessment of candidate vaccines.
P3-S1.40 Frequency and predictors of recommended gonorrhoea therapies in Washington State
Authors: Kerani R , Stenger M , Aubin M , Golden M
Published: July 2011

Background

Washington State (WA) and CDC treatment guidelines recommend ceftriaxone (CFX) as the primary therapy for gonorrhoea (GC), and some evidence suggests that azithromycin (AZM) plus an oral cephalosporin is superior to an oral cephalosporin alone in the treatment of GC.

Methods

We used information from WA GC case report forms submitted July 2009–December 2010 to calculate the proportion of cases receiving different GC therapies. We used log regression to identify factors associated with recommended treatments.

Results

Treatment data were available for 3910 (96%) of 4066 reported GC cases; 2087 (53.4%) were treated with CFX, 931 (23.8%) with cefixime, (533) 13.6% with cefpodoxime, and 359 (9.2%) with another drug. Of 1464 persons receiving an oral cephalosporin, 507 (34.6%) also received AZM. Abstract P3-S1.40 table 1 displays the distribution of single and multidrug therapies for the three most common therapies observed. In a multivariate model, treatment with CFX was associated with male gender (prevalence ratio (PR): 1.23, 95% CI 1.14 to 1.32), Asian/Pacific Islander race (PR: 1.10, 95% CI 1.00 to 1.20) and other/multiple races (PR: 1.13, 95% CI 1.04 to 1.22) (vs White race). Compared to persons treated by private sector medical providers, CFX use was more common among persons treated in STD clinics (PR: 1.65, 95% CI 1.53 to 1.77), ER/urgent care clinics (PR: 1.37, 95% CI 1.25 to 1.50), other hospital settings (PR: 1.27, 95% CI 1.12 to 1.44), or community health centers (PR: 1.14, 95% CI 1.00 to 1.29), and less common among those treated in family planning clinics (PR: 0.38, 95% CI 0.30 to 0.47) and by other provider types (PR: 0.86, 95% CI 0.76 to 0.98). Among persons treated with oral cephalosprins, concurrent treatment with AZM was associated with male gender (PR: 1.71 95% CI 1.45 to 2.01), treatment in an STD clinic (PR: 1.64, 95% CI 1.41 to 1.91) or ER/urgent care clinic (PR: 1.28, 95% CI 1.03 to 1.58) vs by a private provider, having GC only (PR:3.88, 95% CI 2.84 to 5.28) (vs chlamydial coinfection), and Seattle residence (1.32, 95% CI 1.08 to 1.61).

Abstract P3-S1.40 Table 1TotalSingle drug therapyWith AZMWith doxyclyclineWith another drugCeftriaxone2087773 (37.0%)1051 (50.4%)231 (11.1%)32 (1.5%)Cefixime931543 (58.3 %)334 (35.9%)50 (5.4%)4 (0.3%)Cefpodoxime533334 (62.6%)173 (32.5%)25 (4.7%)1 (0.2%)

Conclusions

Approximately half of all persons with gonorrhoea in WA do not receive CFX and over 20% receive an oral cephalosporin alone, which is not recommended in WA guidelines. Efforts to increase CFX should focus on identifying and surmounting barriers to the use of CFX, particularly in places such as family planning clinics and other settings where use is now low.
P3-S2.05 Invasive obstetric procedures and cesarean sections in women with known herpes simplex virus (HSV) status during pregnancy
Authors: Moss N , Gardella C , Drolette L , Magaret A , Wald A
Published: July 2011

Background

Breach of neonatal skin by obstetric procedures during delivery increases risk of neonatal herpes among infants of women with genital HSV infections. We hypothesised that knowledge of genital HSV infection by clinical history or antibody tests (GH/HSV-2) prior to delivery would result in reduced use of invasive obstetric procedures, and we explored whether use of invasive procedures in infected women on suppressive antiviral therapy was similar to use in women without infection.

Methods

We reviewed 750 consecutive deliveries at an academic medical center in 2006; routine prenatal testing included HSV-1 and HSV-2 serostatus. The primary outcome was a composite of invasive delivery procedures (fetal scalp electrodes, artificial rupture of membranes, intrauterine pressure catheter, vacuum extraction or forceps extraction) among women with vs without GH/HSV-2. Women with planned c-sections, multiple gestation pregnancy, or genital herpes lesions at term were excluded.

Results

453 women, including 35 with a history of genital herpes (24 with HSV-2, 11 with HSV-1) and 59 with HSV-2 antibody but no history of genital herpes, were included in the analysis. Of the 94 women with GH/HSV-2, 56 (59.6%) received suppressive antiviral therapy. Among the 38 women with GH/HSV-2 not on suppressive therapy, 15 (39.5%) had an invasive obstetric procedure at delivery compared with 204 (57%) of 359 women without GH/HSV-2 (OR=0.50; 95% CI: 0.25 to 0.98). In contrast, no difference in unplanned c-sections was observed by GH/HSV-2 status (29% vs 28%). Among the 56 women with GH/HSV-2 treated with antiviral therapy, the risk of invasive procedures was similar to that of women without GH/HSV-2, 62.5% vs 57% (OR=1.27; 95% CI 0.71 to 2.26).

Conclusion

Women with known genital herpes or HSV-2 positivity are less likely to undergo invasive procedures that increase the risk of neonatal herpes. However, obstetricians do not appear to avoid these procedures in women who are on suppressive therapy. These data suggest physicians who know their patients' HSV-2 status in pregnancy alter their behaviour to maintain the integrity of neonatal skin. Given the frequency of breakthrough HSV-2 shedding on suppressive antiviral therapy, and the occurrence of neonatal herpes in infants born to women on suppressive therapy, the high frequency of invasive procedure use among women on antiviral therapy is concerning.
P3-S3.04 Clinical screening of sexually transmitted infections and risk factors among people living with HIV at the University Hospital of Cotonou
Authors: Ahouada C , Bashi J , Zannou M D , Gougounon A , Akakpo J , Zinsou R , d'Almeida C , Ahomadegbe C , Azon-kouanou A , Ade G , Houngbe F
Published: July 2011

Background

Many studies have shown an association between the presence of a sexually transmitted infection (STI) and the occurrence of HIV infection. Because of improved prognosis and quality of life due to antiretroviral (ARV), people living with HIV (PLHIV) tend to abandon safer sex practices. The consequence could be the resurgence of sexually transmitted infections. The objective of this study is to determine the prevalence of STIs and associated factors in the population of PLHIV in order to lay appropriate prevention strategies.

Methods

This is a descriptive cross-sectional study conducted from January to February 2011 on PLHIV admitted in consultation at Centre de Traitement ambulatoire, of academic Hospital of Cotonou. An interrogation and urogenital examination were realised systematically by physicians in all patients. STI diagnosis was presumptive, based on observed lesions. The dependent variable studied is the presence of suggestive lesions of STIs. The data entry was made using Epi Data 3.1 and statistical analysis with SAS version 9.2. Proportions were compared using the χ2test. The significance level was 5% and CIs at 95%.

Results

85 patients were recruited, 27 (31.76%) had suggestive lesions of STIs. The STIs lesions found in genitals were: irritation (21.18%), papular lesions (12.94%), discharge (10.59%), ulcers (9.41%), and malodorous vaginal discharge (4.71 %). The presumptive diagnosis raised in front of these lesions were: genital candidiasis (23.53%), genital herpes (8.24%), condyloma (3.53%), Chlamydia (2.35%), syphilis (1.18%). STI prevalence was 25% in patients on ARVs as against 52% among untreated OR 0.30 [0.10 to 0.84], p=0.02. The median CD4 count at diagnosis was 379 cells/μl. The majority of patients, that to say 58%, continues to maintain unprotected sex. They were 24% reported having procreated after knowledge of their positive HIV status. This indicates a risk of sexual transmission of infections.

Conclusion

STIs are frequent in people with HIV even in patients treated with ARVs. Risk behaviours of STIs and HIV transmission are particularly observed in patients whose clinical and immunological status become satisfying. It appears important to emphasise the observance of security measures in monitoring of patients with HIV, especially when their clinical and immunological status are being improved.
P3-S3.08 Sensitivity and specificity of rapid HIV testing in a community setting
Authors: Trottier B , Nguyen V K , Thomas R , Machouf N , Vezina S , O'Brien R , Lavoie S , Longpré D , Boissonnault M , Charest L
Published: July 2011

Background

It was estimated in 2005 that 13% of men who have sex with men (MSM) in Montréal were HIV-positive, and that 23% of these were not aware of their diagnosis. Clinique l'Actuel introduced a pilot rapid HIV testing program using the MedMira kit in 2008. The objective of this study was to describe the sensitivity and specificity of rapid HIV tests in a community based, high HIV risk setting.

Methods

An advertising campaign encouraged MSM and others at risk for HIV to undergo testing through dedicated clinics offering rapid HIV tests. Patients calling for testing deemed at high risk were given appointments within 2 weeks, where they filled out a short questionnaire, received medical consultation routine STI screening, pre- and post- test counselling and their HIV test results within the hour. Those consenting received with a MedMira or and INSTI rapid test and regular HIV screening. Any positive result was confirmed by Western blot.

Results

2500 individuals were tested: 98% men with a median age of 34 (IQR: 26–41). For the MedMira test there were 43 true positives, 2295 true negatives, 13 false positives and four false negatives. 145 patients received the finger-prick INSTI test giving two true positives and 143 true negatives. For MedMira, sensitivity was 91.5% and specificity 99.5% while both figures were 100% for INSTI. The four false negatives were also negative by standard ELISA but positive for P24 antigen. Patients testing positive for HIV had significantly more history of previous STI than those testing negative (p=0.041).

Conclusion

In this setting sensitivity and specificity of the rapid tests used was comparable to standard testing. Acute seroconversion likely explains the four false negatives. As with conventional testing, rapid testing requires adequate counselling about the possibilities of a false negative test. In high-risk populations, routine STI screening should always be performed together with HIV screening.
P1-S1.47 Measuring and prioritising congenital syphilis control in Guangdong China - a Markov model to inform policy implementation
Authors: Tucker J , Tan N , Rydzak C , Yang L G , Peeling R , Chen X S
Published: July 2011

Background

Syphilis is a major public health problem in many regions of China, with increases in congenital syphilis (CS) cases causing particular concern. Precisely determining the extent of CS burden has been challenging given incomplete prenatal screening coverage and limited CS diagnostic capacity. As a result, both net under and over-reporting are plausible. In addition, there are a range of policies that could be expanded as part of the new National Syphilis Control Plan. This paper uses a Markov model to estimate the number of CS cases and other adverse outcomes and prioritise control measures in Guangdong Province, China.

Methods

We developed a Markov model that incorporated age-stratified fertility rates, female adult syphilis reported cases, and empirical syphilis transmission rates to estimate the number of adverse pregnancy outcomes associated with prenatal syphilis infection on a yearly basis from 2005 to 2009. Guangdong Province was the focus of this analysis given access to high quality demographic and public health data required for model inputs. Adverse outcomes examined included CS, stillbirth, neonatal death, and low birth weight. Sensitivity analyses were performed to identify variables most influential for achieving WHO and Chinese program benchmarks.

Results

Our model estimates 264 CS cases per 100 000 live births in Guangdong during 2009, substantially greater than the 129 reported CS cases per 100 000 live births. This is consistent with a net 49% under-reporting of CS cases in 2009. Higher syphilis prevalence among women in their peak childbearing years (20–30 years old) is closely related to greater numbers of CS cases see Abstract P1-S1.47 Figure 1. Expanding prenatal screening coverage was the single most important mechanism for preventing CS cases; increasing prenatal screening from 50% to 100% coverage would be associated with 98 CS cases averted per 100 000 live births. Alternatively, a comprehensive syphilis control strategy including 100% prenatal screening, 100% treatment completion, and 100% early screening in pregnancy would be associated with 212 CS cases averted per 100 000 live births.

Abstract P1-S1.47 Figure 1

Predicted and reported CS cases in Guangdong Province, China, from 2005 to 2009.

Conclusions

Our analysis illustrates the limitations of relying on CS reported cases alone to accurately track adverse pregnancy outcomes associated with syphilis infection in pregnant women. A comprehensive syphilis control strategy targeting universal prenatal screening coverage, treatment completion, and early screening in pregnancy is essential for successful achievement of overall WHO and Chinese CS objectives.
P3-S7.09 Mutations on gyrA or parC genes ofMycoplasma genitaliumand efficacies of treatment with fluoroquinolones againstM genitalium-related urethritis
Authors: Hamasuna R , Takahashi S , Matsumoto M , Sho T , Matsumoto T
Published: July 2011

Background

Mycoplasma genitaliumis one of the pathogens of male urethritis. Macrolides as azithromycin can be the first line-treatment, but macrolides-resistantM genitaliumstrains were isolated. We tried to use some fluoroquinolones againstM genitalium-related urethritis. In these studies, some patients could not treated by fluoroquinolone. In any bacteria, genetic mutations on gyrase genes were related to fluoroquinolone-resistance. In this study, quinolone-resistant determining regions (QRDR) on gyrase genes ofM genitaliumwere analysed and the relationship between the efficacies of fluoroquinolone againstM genitalium-related urethritis and genetic mutations on QRDR ofM genitaliumwas examined.

Methods

The QRDR on gyrA and parC genes ofM genitaliumwere sequenced and analysed. DNA samples were purified fromM genitalium-positive first-voided urine specimens before and after the treatment with fluoroquinolones as gatifloxacin or sitafloxacin. The QRDR of gyrA and parC genes ofM genitaliumwere analysed by using primers according to Shimada's report (Int J Antimicrob Agent, 2010).

Results

Twenty-two genomes ofM genitaliumbefore the treatment with fluoroquinolones and four genomes from patients with treatment-failure were analysed. Before the treatment,M genitaliumgenomes have no mutation on gyrA, but had four mutations on parC gene with amino-changes (Ala-69 to Thr, Pro-72 to Ser, Asp-87 to His and Ser-83 to Ile). After the treatment,M genitaliumwas found in four patients and all remainedM genitaliumwere found mutations on gyrA or parC with amino-changes.M genitaliumwith mutation on parC (Pro-72 to Ser and Ser-83 to Ile) before treatment was remained.M genitaliumwith mutation on parC (Pro-72 to Se and Ser-83 to Ile) before treatment was remained and was found additional gyrA mutation (Asp-99 to Asn). In two patients,M genitaliumwithout mutations before treatment remained after treatment. However, these genomes were found with newer mutations on gyrA (Asp-99 to Asn) or on parC (Ser-83 to Ile).

Conclusion

From the urine specimens of patients with treatment-failure of fluoroquinolones, some mutations with amino-change were found on QRDR of gyrA or parC genes ofM genitalium. It was suggested that these mutations are related with treatment-failure with fluoroquinolones.
P4-S1.04 11C-Choline small animal PET in experimentalChlamydia muridaruminfection
Authors: Marangoni A , Nanni C , Quarta C , Aldini R , Donati M , Nardini P , Foschi C , Fanti S , Cevenini R
Published: July 2011

Objectives

Genital tract infection of female mice withChlamydia muridarumclosely mimicsC trachomatisacute genital tract infection in women. Aim of this study was to assess the predictivity of 11C-Choline Small Animal PET for the identification of reactive animals and their follow-up at several times after vaginal challenge.

Methods

Chlamydiae were grown in LLC-MK2 cells, cultivated in Eagle's MEM and elementary bodies were purified from cells by sucrose-gradients density centrifugation. Animals used in this study were 10 female Balb/c mice, 6–8 weeks old. All the animals received 2.5 mg of medroxyprogesterone acetate intramuscular nine and 2 days prior the infection. Nine mice were infected by placing 106 IFUs ofC muridaruminto the vaginal vault. Infection was induced under Ketamine anaesthesia. As control, one animal was challenged with SPG. At 5, 10 and 20 days after challenge mice underwent a 11C-Choline PET, as follows: each animal was anaesthetised with Sevofluorane 3–5% oxygen 1 l/min and was injected with approximately 20 MBq of 11C-Choline, via the tail vein. The residual dose was measured to verify the effective dose injected. The animal was subsequently placed on the scanner bed in the prone position, after an uptake time of 5 min. Images were acquired with a small animal PET tomograph (GE, eXplore Vista DR) for a total acquisition time of 20 min. As the axial field of view was 4 cm, one bed position was sufficient to cover the whole body. Images were reconstructed iteratively (OSEM 2D) and read in three planes (axial, sagittal and coronal). The scan was considered positive if areas of increased Choline uptake were present at sites consistent with the site of inflammation. The standard uptake value (SUV) was calculated by measuring the concentration of the labelled tracer in the region of interest and correcting it for mice body weight and injected dose. Infection was monitored by culturing cervical-vaginal secretions 6, 11 and 21 days after infection.

Results

At 5 days, the mean vaginal SUV (±SD) of the cases was 0.83±0.39, whereas the control showed a value of 0.278. At 10 and 20 days, SUVs of the cases were 0.94±0.25 and 1.17±0.21, respectively, whereas SUV of the control was 0.299 and 0.302, respectively.C muridarumwas isolated from all the infected animals during the study period.

Conclusions

These preliminary data indicate that 11C-Choline PET could be a promising technique to in vivo evaluate inflammatory response to Chlamydia infection.
P4-S1.09 Development of a microwave: accelerated metal-enhanced fluorescence 40 s, <100 cfu/ml point of care assay for the detection ofChlamydia trachomatisandNeisseria gonorrhoea
Authors: Geddes C , Zhang Y , Melendez J , Gaydos C
Published: July 2011

Chlamydia trachomatis(CT) is the most prevalent bacterial sexually transmitted infection (STIs) reported to the Centers for Disease Control and Prevention (CDC). There were 1.2 million cases of chlamydia reported to the CDC in 2008.Neisseria gonorrhoeae(GC) is also one of the most prevalent sexually transmitted infections in men and women. In 2009, there were 301 174, cases reported to the CDC, a rate of 99.1 per 100 000 populations. The CDC estimates that STIs cost the healthcare system $1.5 billion annually. Subsequently, there is an urgent need to develop a low cost sensitive and specific rapid diagnostic test to detect bacterial sexually transmitted infections. To this end, an exciting, novel and rapid technology, which integrates power lysis” and MAMEF (Microwave-Accelerated Metal-Enhanced Fluorescence), to both lyse CT and GC and detect the DNA released from CT and GC and combined CT and GC samples, within 40 s, is demonstrated. In a microwave cavity, 2.45 GHz microwave energy is highly focused into a lysing chamber, using 100 nm thick gold films with “bow-tie” structures, to lyse the bacteria within 10 s. The ultrafast detection of the released DNA from <100 cfu/ml bacteria is accomplished in an additional 30 s by employing the microwave-accelerated metal-enhanced fluorescence (MAMEF) technique. This new “release and detect” platform technology is a highly attractive alternative method for the lysing of bacteria, DNA extraction and the fast quantification of bacteria and potentially many other pathogenic species and cells as well. Our approach is a significant step forward for the development of a point of care test for bacteria.
P4-S4.04 Temporal dynamics of vaginal bacterial communities
Authors: Ravel J , Brotman R , Gajer P , Sakamoto J , Koenig S , Fu L , Zhou X , Abdo Z , Forney L , Ravel J
Published: July 2011

Background

Dysbiosis of vaginal bacterial communities have been associated with increased risk for sexually transmitted infections and bacterial vaginosis. This is the first observational study to model temporal dynamics of vaginal microbiota using frequently collected samples, behavioural data and culture-independent methods.

Methods

Thirty-three asymptomatic, reproductive-age women self-collected mid-vaginal swabs every 3rd day for 16 weeks (998 samples). Participants reported behaviours and menstrual data on daily diaries. Bacterial communities were determined by pyrosequencing of barcoded 16S rRNA genes (V1–V2 region). Participants were clustered into five community classes based on temporal patterns of vaginal bacterial community composition using transition probabilities. A linear mixed effect model for the log of Jensen-Shannon rate of community change was utilised. The model accounted for correlations between samples from the same participant and was adjusted for time-varying confounders and normalised menstrual cycle time.

Results

Three of the community classes were most often dominated byLactobacillus iners,L crispatus, orL gasseri, respectively, while two lacked significant numbers ofLactobacillusspp. The latter classes were split into subtype A typified by Corynebacterium, Anaerococcus, Peptinophilus, Prevotella, and Finegoldia, while those of subtype B showed a higher abundance of the genus Atopobium. The rank abundance and species composition of bacterial communities in some women changed markedly over short periods of time while others were relatively stable. Classes dominated byL crispatusandL gasseriexperienced the fewest fluctuations in community composition, and communities that lacked significant number ofLactobacillus spp. also demonstrated some stability. Vaginal communities dominated byL inersdemonstrated either a lack of constancy or notable stability. The menstrual cycle was associated with temporal dynamics, but these effects were influenced by bacterial community class. Sexual activity the day prior to sampling was of borderline statistical significance (p=0.065) and is a variable of interest in supplementary modelling.

Conclusions

Vaginal microbiota can fluctuate rapidly. Future studies should investigate the role of temporal changes in vaginal microbiota on sexually transmitted infection risk. Longitudinal studies of the vaginal microbiome may allow for the future development of targeted individualised therapeutic approaches.
P5-S3.05 A clinical practice intervention to increase chlamydial screening: sustaining the gain and translating into practice 4 years later
Authors: Tebb K , Shafer M A
Published: July 2011

Background

Chlamydia trachomatis(CT) continues to be a major public health problem among sexually active adolescent and young adult females. Although annual CT screening is recommended, actual rates remain low. System-based interventions are an effective approach to improve clinical practice including CT screening.

Objective

There are two objectives: (1) To describe the sustainability of a systems-based, clinical practice improvement intervention to increase urine-based CT screening among adolescent girls (14–18 years old) during routine check-ups in a paediatric clinic setting (2) To describe and evaluate the translation of this intervention into control clinics.

Methods

The study randomised 10 paediatric clinics (5 experimental, 5 control) within a large Northern California health maintenance organization (HMO). Clinics in the experimental group received a systems-based clinical practice improvement intervention (CPI) and controls received a traditional provider education intervention. The original study took place between 2000 and 2002 (Shaferet al JAMA, 2002). After the study ended, the intervention was translated to the remaining clinics including to the five controls. Data were tracked for four additional years (2003–2006). The proportion of 14–18-year-old girls who had sexual intercourse and who were screened for CT during their routine checkups was calculated using the same methodology as the original study. We assessed changes in the rate variable over time, within sites and between the intervention and control groups using linear mixed effects models with random intercepts.

Results

The average screening rate in the intervention group was sustained at an average of 60% during the 4-year follow-up period (CI 0.41 to 0.79) with no significant increases over time. Prior to translation activities, the proportion screened in controls was 21%. After translation activities, the control group exhibited statistically significant linear and quadratic effects of time (p=0.0019 by Wald χ2test). The estimated rate for the controls was 0.42 (95% CI 0.25 to 0.59) at time 1, increased to a maximum of 0.69 (95% CI 0.55 to 0.83) at year 2.5, then declined to 0.52 (95% CI 0.35 to 0.70) at the end of year 4.

Conclusions

This CPI systems intervention was both translatable and sustainable to other paediatric clinics within this HMO.
P5-S4.06 Sticking to it: the effect of maximally assisted therapy on antiretroviral treatment adherence among a cohort of unstably housed people living with HIV in BC, Canada
Authors: Parashar S , Palmer A , O'Brien N , Chan K , Shen A , Coulter S , Montaner J , Hogg R
Published: July 2011

Background

Housing is a known determinant of health behaviour, including adherence to antiretroviral therapy. Within the Longitudinal Investigations into Supportive and Ancillary Health Services (LISA) cohort, unstable housing is inversely associated with adherence. The Maximally Assisted Therapy (MAT) program uses a multidisciplinary approach to support people living with HIV/AIDS (PHA) who have a history of addictions, mental health disorders and homelessness. We investigated the efficacy of support services, including the MAT program, in improving adherence for unstably housed PHA.

Methods

The LISA cohort is a cross-sectional study of individuals on antiretroviral therapy in British Columbia. Interviewer-administered surveys collect information regarding housing, drug use, utilisation of health services and other clinically relevant socio-demographic factors. Clinical variables, such as CD4 count and viral load, were obtained through longitudinal linkages with the Drug Treatment Program (DTP) at the BC Centre for Excellence in HIV/AIDS. Logistic regression was used to determine factors associated with adherence (≥95% vs <95%) among unstably housed LISA participants (n=212).

Results

Between 2007 and 2010 approximately 1000 participants were interviewed. This analysis is based on 644 interviews, of which the DTP reports optimal adherence [≥95% 12 month refill] for 367 (57%) individuals. Median age was 46 and 475 (73.7%) were male. We found that unstably housed participants attending the MAT program were 4.76 times more likely to be ≥95% adherent [95% CI 1.72 to 13.13] than those who did not. Other factors associated with optimal adherence included recent incarceration (Adjusted OR [AOR]=0.20 [95% CI 0.05 to 0.80]) and not currently using illicit drugs (AOR=0.40 [95% CI 0.16 to 0.99]).

Conclusion

The MAT program provides a model for other urban centers dealing with concurrent and interrelated adherence barriers: high-risk drug use, mental health disorders and homelessness. In the absence of sustainable housing solutions, programs such as MAT are crucial to achieving optimal treatment adherence in this population.
P5-S5.08 Efficient gonorrhoea and chlamydia control and prevention through partner notification in high morbidity STD states: a Louisiana perspective
Authors: Rahman M , Khan M , Longfellow L
Published: July 2011

Background

Case detection through screening and partner notification are the two strategies used by the state Sexually Transmitted Disease (STD) Control Programs in USA for STD control and prevention. Most of the state programs do not use partner notification for Gonorrhoea and Chlamydia cases because of lack of personnel and financial resources. To focus the limited resources in high morbidity STD states, partner notification is solely targeted towards syphilis and HIV cases. However, systematic analysis is needed to understand the effectiveness of partner notification for STDs other than syphilis and HIV cases. The objective of this study is to carryout partner notification via telephone of Gonorrhoea and Chlamydia cases detected in two STD/ Family Planning clinics in Louisiana.

Methods

All Gonorrhoea and Chlamydia cases detected at two STD/Family Planning clinics (pilot sites) were selected for telephone interview. Three trained telephone interviewers are provided with the contact information of positive cases. The interviewers made up to seven attempts to interview the index cases. Information regarding sexual partners and contact information was obtained from the interviewed cases. Later the partners were notified for testing and treatment.

Results

From July to December 2010, 512 Gonorrhoea and Chlamydia cases were detected at these two pilot sites and 237 cases (46.3%) were interviewed. Missing valid contact numbers and inability to contact the case by the seventh attempt were the main reasons for the relatively low interview rate. A total of 129 partners were elicited from 237 index cases. 87 partners (67.4%) sought medical evaluation, 49 partners (37.9%) were infected and treated, and 38 partners (29.5%) received preventive treatment.

Conclusion

Our study shows that partner elicitation and notification for Gonorrhoea and Chlamydia cases via telephone can be an effective mechanism in high morbidity STD areas. In our pilot testing, 100 patients provided information on additional 54 contacts and 100 index cases lead to treatment of additional 21 cases. Treatment of these 21 cases and preventive treatment of additional cases should have significant impact on overall prevalence of the diseases if the program is adopted at the state level, especially in the high morbidity STD states.
P5-S6.01 Towards universal access to prevention mother to child HIV-transmission (PMTCT) services leading to elimination of mother to child HIV-transmission (MTCT) in Rwanda
Authors: Nyemazi J P
Published: July 2011

Background

PMTCT related activities in Rwanda began in 1999 with a piloting phase in Kicukiro Health Centre in Kigali City. Subsequently, PMTCT service delivery has been expanded and over 74% of total health facilities are covered in the country.

Objectives

In May 2010, Rwanda commissioned the Mid-term review of PMTCT scale up plan in order to document achievements made, best practices, challenges faced and guide a development of MTCT elimination plan.

Methods

Mid-term review was a cross-sectional descriptive and analytical study employing rapid participatory assessment techniques. Data collection was undertaken at national level and 15 selected health facilities located in five districts. In-depth interviews with local authorities, providers and HIV-infected mothers were conducted. Key programmatic indicators data were gathered. Data analysis was done using a range of qualitative techniques and secondary quantitative data.

Results

In Rwanda, 96% of pregnant women attend antenatal care (ANC) at least once during pregnancy and receive HIV testing and counselling. In 2009, over 74% of pregnant women attended PMTCT sites and 97% of them got tested and received their HIV results. Of the expected HIV infected pregnant mothers, 78% actually received antiretroviral prophylaxis for the PMTCT. Of the expected HIV exposed infants, 64.3% actually received antiretroviral prophylaxis and the rate of MTCT dropped from 10.4% (2007) to 4.1% at 18 months of age in 2009.

Conclusions

The review showed that significant progress has been made in achieving national PMTCT targets; however there is a need for interventions to increase the uptake for the PMTCT program in the country to achieve the Millennium development Goals (MDG).

Implications

Rwanda is on-track to attain MDGs and the review findings lead to the development plan aiming at elimination of MTCT in Rwanda by 2012.
P1-S2.10 Female clients and partners of MSM sex workers in a resource-poor setting, West Africa
Authors: Busari O , Nakayima M , Busari A
Published: July 2011

MSM are becoming increasingly important in HIV epidemics in Africa and their population is growing in Nigeria. However, there's paucity of data on HIV epidemics in MSM in Nigeria and West Africa region. Though HIV transmission in Africa is mainly heterosexual, interactions between HIV epidemics in MSM and heterosexual populations are not well understood. Objective was to describe female clients and partners of MSM sex workers (MSM-SW) in Lagos and to determine risk factors for unprotected sex between women and MSM-SW.

Methods

MSM were recruited through respondent driven sampling, a novel methodology designed to access hidden populations. MSM-SW were identified through self-reporting and consent was obtained. Participants completed a pre-tested questionnaire and a behaviour diary. The questionnaire included questions on details of each sexual partner for 4 weeks; each sexual encounter with each partner; and the three most recent partnerships. Data were summarised as proportions and compared using chi square test.

Results

62 MSM-SW participated in the study and concluded the self-reported questionnaire and behaviour diary. MSM-SW recorded 311 partners, out of which 66(21.2%) were female and aged between 16 and 38 years. Thirty-two (10.3%) were recent female partners. Of the recent female partners, 17 (53.1%) were unmarried, 14 (43.8%) married and one was a spouse of MSM-SW. 60 (90.1%) of female partners of MSM-SW paid or were paid for sex (39/60,65% paid MSM-SW while 21/60, 35% were paid by them). There were 52 single episode sexual contacts and 14 regular partnerships. Of the 50 new transactional contacts, more than half (56%) met in the bars, restaurants, clubs, motels and beaches. All the sexual encounters between MSM-SW and their female partners involved penetrative sex—vaginal sex (VS)(53, 80%); anal sex (AS)(39, 59%); and both (31, 47%). Unprotected sex was significantly more frequently associated with sex with regular partner than with single episode sexual contact (79% vs 52%; p=0.02, OR=3.0) and non-transactional sex than sex paid for by the female partners (71% vs 46%; p=0.029,OR=2.8).

Conclusion

MSM-SW in Nigeria have a lot of female clients and partners and frequently engage in transactional and unprotected sex with them. Majority of these female partners are in heterosexual married relationships. Understanding these interactions between MSM and heterosexual populations is very crucial to any HIV intervention targeted on MSM and by extension the general population.