Dionne Gesink

Mycoplasma genitalium presence, resistance and epidemiology in Greenland

Objectives . Greenland reports the highest rates of chlamydial infection and gonorrhea in the Arctic. Our objective was to determine the presence, and describe the basic epidemiology, of Mycoplasma genitalium for Greenland. Study design . Cross-sectional study. Methods . 314 residents from Nuuk and Sisimiut, between the ages of 15 and 65 years, participated in “Inuulluataarneq” (the Greenland Sexual Health Project) between July 2008 and November 2009. Participants provided self-collected samples for sexually transmitted infection (STI) testing and completed a sexual health survey. Descriptive statistics and logistic regression were used to summarize the basic characteristics of STI cases overall and M. genitalium and Chlamydia trachomatis specifically. Clinically relevant characteristics in each full model were gender (male or female), age (in years), age at sexual debut (in years), number of sexual partners in the past 3 months (continuous) and history of forced sex and community. Results . The overall prevalence of STIs was 19.0%, specifically: 9.8% for M. genitalium and 9.4% for C. trachomatis; 100% of M. genitalium-positive cases carried macrolide resistance determinants. Being female [OR = 3.2; 95% confidence interval (CI): 1.1–9.8] and younger age (OR = 0.9; 95% CI: 0.9–1.0) were associated with M. genitalium positivity. Age was also associated with C. trachomatis (OR = 0.9; 95% CI: 0.8–0.9) and STI positivity overall (OR = 0.9; 95% CI: 0.9–0.9). Conclusions . We observed a high prevalence of M. genitalium and macrolide resistance in this study. A better understanding of M. genitalium sequelae is needed to inform policy around testing, treatment, control and antibiotic use.

Mapping Health Data: Improved Privacy Protection With Donut Method Geomasking

A major challenge in mapping health data is protecting patient privacy while maintaining the spatial resolution necessary for spatial surveillance and outbreak identification. A new adaptive geomasking technique, referred to as the donut method, extends current methods of random displacement by ensuring a user-defined minimum level of geoprivacy. In donut method geomasking, each geocoded address is relocated in a random direction by at least a minimum distance, but less than a maximum distance. The authors compared the donut method with current methods of random perturbation and aggregation regarding measures of privacy protection and cluster detection performance by masking multiple disease field simulations under a range of parameters. Both the donut method and random perturbation performed better than aggregation in cluster detection measures. The performance of the donut method in geoprivacy measures was at least 42.7% higher and in cluster detection measures was less than 4.8% lower than that of random perturbation. Results show that the donut method provides a consistently higher level of privacy protection with a minimal decrease in cluster detection performance, especially in areas where the risk to individual geoprivacy is greatest.

Geomasking sensitive health data and privacy protection: an evaluation using an E911 database

Geomasking is used to provide privacy protection for individual address information while maintaining spatial resolution for mapping purposes. Donut geomasking and other random perturbation geomasking algorithms rely on the assumption of a homogeneously distributed population to calculate displacement distances, leading to possible under-protection of individuals when this condition is not met. Using household data from 2007, we evaluated the performance of donut geomasking in Orange County, North Carolina. We calculated the estimated k-anonymity for every household based on the assumption of uniform household distribution. We then determined the actual k-anonymity by revealing household locations contained in the county E911 database. Census block groups in mixed-use areas with high population distribution heterogeneity were the most likely to have privacy protection below selected criteria. For heterogeneous populations, we suggest tripling the minimum displacement area in the donut to protect privacy with a less than 1% error rate.

Relative risk of cervical cancer in indigenous women in Australia, Canada, New Zealand, and the United States: A systematic review and meta-analysis

We performed a systematic review and meta-analysis of cervical cancer risk in indigenous women in Australia, Canada, New Zealand, and the United States, in order to identify whether risks of cervical dysplasia, cervical cancer, and cervical cancer-related mortality are higher in indigenous relative to non-indigenous populations. We identified 35 studies published in 1969–2008. In our findings, indigenous populations did not have an elevated risk of cervical dysplasia or carcinoma in situ relative to non-indigenous populations, but had elevated risks of invasive cervical cancer (pooled RR=1.72) and cervical cancer-related mortality (pooled RR=3.45). There was a log-linear relationship between relative risk and disease stage. In conclusion, the indigenous women have a markedly higher risk of cervical cancer morbidity and mortality than non-indigenous women, but no increased risk of early-stage disease, suggesting that structural, social, or individual barriers to screening, rather than baseline risk factors, are influencing poor health outcomes.

Vaginal microbiome in women from Greenland assessed by microscopy and quantitative PCR

BackgroundBacterial vaginosis (BV) is a common condition, although its aetiology remains unexplained. The aim of this study was to analyse the composition of vaginal microbiota in women from Greenland to provide a quantitative description and improve the understanding of BV.MethodsSelf-collected vaginal smears and swabs were obtained from 177 women. The vaginal smears were graded for BV according to Nugent’s criteria. The vaginal swab samples were analysed by 19 quantitative PCRs (qPCRs) for selected vaginal bacteria and by PCR for four sexually transmitted infections (STIs).ResultsSTIs were common: Mycoplasma genitalium 12%, Chlamydia trachomatis 7%, Neisseria gonorrhoeae 1%, and Trichomonas vaginalis 0.5%. BV was found in 45% of women, but was not associated with individual STIs. Seven of the 19 vaginal bacteria (Atopobium vaginae, Prevotella spp., Gardnerella vaginalis, BVAB2, Eggerthella-like bacterium, Leptotrichia amnionii, and Megasphaera type 1) had areas under the receiver operating characteristic (ROC) curve > 85%, suggesting they are good predictors of BV according to Nugent. Prevotella spp. had the highest odds ratio for BV (OR 437; 95% CI 82–2779) in univariate analysis considering only specimens with a bacterial load above the threshold determined by ROC curve analysis as positive, as well as the highest adjusted odds ratio in multivariate logistic regression analysis (OR 4.4; 95% CI 1.4-13.5). BV could be subdivided into clusters dominated by a single or a few species together.ConclusionsBV by Nugent score was highly prevalent. Two of seven key species (Prevotella spp. and A. vaginae) remained significantly associated with BV in a multivariate model after adjusting for other bacterial species. G. vaginalis and Prevotella spp. defined the majority of BV clusters.

Developing a culturally competent and socially relevant sexual health survey with an urban arctic community

Objectives. To develop a culturally competent and socially relevant sexual health survey for people living in Nuuk, Greenland, aged 15 years and older. Study Design. Qualitative study with interviews. Methods. Community and research informants (n=10) were interviewed informally to identify survey topics. A sexual health survey was constructed combining local knowledge from informants with a review of sexual health literature for the Arctic and other Indigenous locations. The draft survey was distributed to community partners for commentary and revision. After translation into Danish and Greenlandic, cognitive interviews were conducted with 11 Nuuk residents, identified through snowball sampling, to both pilot test the survey and exchange social and cultural knowledge relevant to sexual health in Nuuk. The utility of this process was evaluated against implementation of the final survey to Nuuk residents enrolled in Inuulluataarneq (n=149). Results. Theme saturation was reached by the ninth interview. STI risk and self-efficacy, co-occurrence of alcohol use and sex and STI knowledge were identified as most relevant. Questions about community efficacy, culture/community involvement and identity were most sensitive. Upon implementation of the final survey, 146 of 149 participants answered all survey questions. Two Elder participants refused to answer questions about sex. Some questions had low response variability but still added to our contextual understanding and helped to build rapport with participants. Conclusions. Combining an iterative process with community-based participatory research principles and cognitive interview techniques was an effective method for developing a sexual health survey with Nuuk residents.

Are Neighborhood Sociocultural Factors Influencing the Spatial Pattern of Gonorrhea in North Carolina

PURPOSE To determine if the spatial pattern of gonorrhea observed for North Carolina was influenced by neighborhood-level sociocultural determinants of health, including race/ethnicity. METHODS A generalized linear mixed model with spatially correlated random effects was fit to measure the influence of socio-cultural factors on the spatial pattern of gonorrhea reported to the North Carolina State Health Department (January 1, 2005 to March 31, 2008). RESULTS Neighborhood gonorrhea rates increased as the percent single mothers increased (25th to 75th neighborhood percentile Relative Rate 1.18, 95% CI 1.12, 1.25), and decreased as socioeconomic status increased (Relative Rate 0.89, 95% CI 0.84, 0.95). Increasing numbers of men in neighborhoods with more women than men did not change the gonorrhea rate, but was associated with decreased rates in neighborhoods with more men than women. Living in the mountains was protective for all race/ethnicities. Rurality was associated with decreased rates for Blacks and increased rates for Native Americans outside the mountains. PURPOSE Neighborhood-level sociocultural factors, primarily those indicative of neighborhood deprivation, explained a significant proportion of the spatial pattern of gonorrhea in both urban and rural communities. Race/ethnicity was an important proxy for social and cultural factors not captured by measures of socioeconomic status.

Who are the under- and never- screened for cancer in Ontario: a qualitative investigation

BackgroundObserved breast, cervical and colon cancer screening rates are below provincial targets for the province of Ontario, Canada. The populations who are under- or never-screened for these cancers have not been described at the Ontario provincial level. Our objective was to use qualitative methods of inquiry to explore who are the never- or under-screened populations of Ontario.MethodsQualitative data were collected from two rounds of focus group discussions conducted in four communities selected using maps of screening rates by dissemination area. The communities selected were archetypical of the Ontario context: urban, suburban, small city and rural. The first phase of focus groups was with health service providers. The second phase of focus groups was with community members from the under- and never- screened population. Guided by a grounded theory methodology, data were collected and analyzed simultaneously to enable the core and related concepts about the under- and never-screened to emerge.ResultsThe core concept that emerged from the data is that the under- and never-screened populations of Ontario are characterized by diversity. Group level characteristics of the under- and never- screened included: 1) the uninsured (e.g., Old Order Mennonites and illegal immigrants); 2) sexual abuse survivors; 3) people in crisis; 4) immigrants; 5) men; and 6) individuals accessing traditional, alternative and complementary medicine for health and wellness. Under- and never-screened could have one or multiple group characteristics.ConclusionThe under- and never-screened in Ontario comprise a diversity of groups. Heterogeneity within and intersectionality among under- and never-screened groups adds complexity to cancer screening participation and program planning.

Perceived HIV risk, actual sexual HIV risk and willingness to take pre-exposure prophylaxis among men who have sex with men in Toronto, Canada.

ABSTRACT Pre-exposure prophylaxis (PrEP) reduces HIV acquisition. Our goal was to determine the willingness of men who have sex with men (MSM) to take PrEP given perceived and actual HIV risk. HIV-negative MSM were recruited from September 2010 to June 2012 and asked about PrEP willingness and perceived HIV risk. Actual sexual HIV risk was measured by three condom-use components generated through principal components analysis. General HIV risk was measured using the HIV Incidence Risk Index for MSM (HIRI-MSM). Model 1 measured PrEP willingness given perceived and actual sexual HIV risk. Model 2 included actual HIV sexual risk, perceived HIV risk and general HIV risk. Model 3 removed actual sexual HIV risk. We recruited 150 HIV-negative MSM. About 55% were willing to take PrEP. Reasons for PrEP unwillingness were: low perceived risk (64%), side-effect concerns (44%), daily pill burden (16%) and efficacy concerns (4%). Model 1: MSM with high compared to low actual sexual HIV risk were more willing to use PrEP (OR 27.11, 95% CI 1.33–554.43) after adjusting for perceived risk, which was not significantly associated with PrEP willingness (OR 4.79, 95% CI 0.72–31.96). Model 2: MSM with high compared to low actual sexual HIV risk were more willing to use PrEP (OR 29.85, 95% CI 1.39–640.53) after adjusting for perceived and general HIV risk, neither of which was significantly associated with PrEP willingness (OR 5.07, 95% CI 0.73–35.09) and (OR 1.58, 95% CI 0.37–6.79), respectively. Model 3: After removing actual sexual HIV risk, MSM with high compared to low perceived risk were more willing to use PrEP (OR 6.85, 95% CI 1.23–38.05), and the HIRI-MSM general risk index was not associated with PrEP willingness (OR 1.87, 95% CI 0.54–6.54). Therefore, actual sexual HIV risk was the best predictor of PrEP willingness and general HIV risk did not inform PrEP willingness.

Log Gaussian Cox processes and spatially aggregated disease incidence data.

This article presents a methodology for modeling aggregated disease incidence data with the spatially continuous log-Gaussian Cox process. Statistical models for spatially aggregated disease incidence data usually assign the same relative risk to all individuals in the same reporting region (census areas or postal regions). A further assumption that the relative risks in two regions are independent given their neighbors risks (the Markov assumption) makes the commonly used Besag–York–Mollié model computationally simple. The continuous model proposed here uses a data augmentation step to sample from the posterior distribution of the exact locations at each step of an Markov chain Monte Carlo algorithm, and models the exact locations with an log-Gaussian Cox process. A simulation study shows the log-Gaussian Cox process model consistently outperforming the Besag–York–Mollié model. The method is illustrated by making inference on the spatial distribution of syphilis risk in North Carolina. The effect of several known social risk factors are estimated, and areas with risk well in excess of that expected given these risk factors are identified.