Social and Behavioral Determinants of Sexually Transmitted Disease: Scientific and Technologic Advances, Demography, and the Global Political Economy

The female reproductive tract virome: understanding the dynamic role of viruses in gynecological health and disease

The human body is inhabited by a large and complex network of commensal and predatory eukaryotic viruses and bacteriophages collectively termed the virome. Despite being the most abundant and genetically diverse biological entities on the planet, the impact of viruses on human health especially within the female reproductive tract (FRT) remains understudied. To better appreciate current knowledge regarding the dynamic role of viruses in FRT health and disease, in this review we highlight the known constituents of the FRT virome, transkingdom interactions within the FRT and their influence on gynecological disease. A better understanding of the FRT virome may pave the way toward improved outcomes in gynecological, reproductive, and neonatal health.

Investigating Multiple-Reported Bacterial Sexually Transmitted Infection Hot Spot Counties in the United States: Ordered Spatial Logistic Regression

PURPOSE

To identify and examine the correlates of multiple bacterial sexually transmitted infection (STI) hot spot counties in the United States.

METHODS

We assembled and analyzed 5 years (2008-2012) of cross-sectional STI morbidity data to identify multiple bacterial STI (chlamydia, gonorrhea, and syphilis) hot spot counties using hot spot analysis. Then, we examined the association between the multi-STI hot spots and select multiyear (2008-2012) sociodemographic factors (data obtained from the American Community Survey) using ordered spatial logistic regression analyses.

RESULTS

Of the 2935 counties, the results indicated that 85 counties were hot spots for all 3 STIs (3-STI hot spot counties), 177 were hot spots for 2 STIs (2-STI hot spot counties), and 145 were hot spots for only 1 STI (1-STI hot spot counties). Approximately 93% (79 of 85) of the counties determined to be 3-STI hot spots were found in 4 southern states--Mississippi (n = 25), Arkansas (n = 22), Louisiana (n = 19), and Alabama (n = 13). Counties determined to be 2 STI hot spots were found in 7 southern states--Arkansas, Louisiana, Mississippi, Alabama, Georgia, and North and South Carolina had at least ten 2-STI hot spot counties each. The multi-STI hot spot classes were significantly (P < 0.05) associated with percent black (non-Hispanic), percent Hispanics, percent American Indians, population density, male-female sex ratio, percent aged 25 to 44 years, and violent crime rate.

CONCLUSIONS

This study provides information on multiple STI hot spot counties in the United States and the associated sociodemographic factors. Such information can be used to assist planning, designing, and implementing effective integrated bacterial STI prevention and control programs/interventions.

A taxonomy of the scope and organization of local sexually transmitted disease services for policy and practice

Local health departments (LHDs) and their organizational partners play a critical role in controlling sexually transmitted diseases (STDs) in the United States. We examine variation in the differentiation, integration, and concentration (DIC) of STD services and develop a taxonomy describing the scope and organization of local STD services. LHD STD programs (n = 115) in Alabama (AL) and California (CA) responded to surveys assessing STD services available in 2014. K-means cluster analysis identified LHD groupings based on DIC variation. Discriminant analysis validated cluster solutions. Differences in organizational partnerships and scope of STD services were compared by taxonomy category. Multivariable regression models estimated the association of the STD services organization taxonomy and five-year (2010–2014) gonorrhea incidence rates, controlling for county-level sociodemographics and resources. A three-cluster solution was identified: (1) low DIC (n = 74), (2) moderate DIC (n = 31), and (3) high DIC (n = 10). In discriminant analysis, 95% of jurisdictions were classified into the same types as originally assigned through K-means cluster analysis. High DIC jurisdictions were more likely (p < 0.001) to partner with most organizations than moderate and low DIC jurisdictions, and more likely (p < 0.001) to conduct STD needs assessment, comprehensive sex education, and targeted screening. In contrast, contact tracing, case management, and investigations were conducted similarly across jurisdictions. In adjusted analyses, there were no differences in gonorrhea incidence rates by category. Jurisdictions in CA and AL can be characterized into three distinct clusters based on the DIC of STD services. Taxonomic analyses may aid in improving the reach and effectiveness of STD services.

The Effects of School-Based Discrimination on Adolescents of Color Sexual Health Outcomes: A Social Determinants Approach

Social inequalities are at the heart of disparities in sexual health outcomes among African American and Latino/a adolescents living in the United States. Schools are typically the largest and primary context in youth development. School characteristics such as peer and teacher discrimination and school performance were examined to determine whether such characteristics predict sexual behavior in adolescents of color. This study utilized a representative sample of high school age students to assess sexual risk behavior. Findings indicate that there was a clear disparity in sexually transmitted infection diagnoses. School characteristics such as teacher discrimination and Grade Point Average were significant predictors to sexual risky behaviors among adolescents of color. The study adds to the literature in examining contextual factors that are associated with adolescent sexual risk behavior, and findings provide implications for future prevention work.

Correlates of county-level nonviral sexually transmitted infection hot spots in the US: application of hot spot analysis and spatial logistic regression

PURPOSE

We used a combination of hot spot analysis (HSA) and spatial regression to examine county-level hot spot correlates for the most commonly reported nonviral sexually transmitted infections (STIs) in the 48 contiguous states in the United States (US).

METHODS

We obtained reported county-level total case rates of chlamydia, gonorrhea, and primary and secondary (P&S) syphilis in all counties in the 48 contiguous states from national surveillance data and computed temporally smoothed rates using 2008-2012 data. Covariates were obtained from county-level multiyear (2008-2012) American Community Surveys from the US census. We conducted HSA to identify hot spot counties for all three STIs. We then applied spatial logistic regression with the spatial error model to determine the association between the identified hot spots and the covariates.

RESULTS

HSA indicated that ≥84% of hot spots for each STI were in the South. Spatial regression results indicated that, a 10-unit increase in the percentage of Black non-Hispanics was associated with ≈42% (P < 0.01) [≈22% (P < 0.01), for Hispanics] increase in the odds of being a hot spot county for chlamydia and gonorrhea, and ≈27% (P < 0.01) [≈11% (P < 0.01) for Hispanics] for P&S syphilis. Compared with the other regions (West, Midwest, and Northeast), counties in the South were 6.5 (P < 0.01; chlamydia), 9.6 (P < 0.01; gonorrhea), and 4.7 (P < 0.01; P&S syphilis) times more likely to be hot spots.

CONCLUSION

Our study provides important information on hot spot clusters of nonviral STIs in the entire United States, including associations between hot spot counties and sociodemographic factors.

The relationship between multiple sex partners and anxiety, depression, and substance dependence disorders: a cohort study

Changes in sexual behavior have resulted in longer periods of multiple serial or concurrent relationships. This study investigated the effects of multiple heterosexual partners on mental health, specifically, whether higher numbers of partners were linked to later anxiety, depression, and substance dependency. Data from the Dunedin Multidisciplinary Health and Development Study, a prospective, longitudinal study of a birth cohort born in 1972-1973 in Dunedin, New Zealand were used. The relationship between numbers of sex partners over three age periods (18-20, 21-25, and 26-32 years) and diagnoses of anxiety, depression, and substance dependence disorder at 21, 26, and 32 years were examined, using logistic regression. Interaction by gender was examined. Adjustment was made for prior mental health status. There was no significant association between number of sex partners and later anxiety and depression. Increasing numbers of sex partners were associated with increasing risk of substance dependence disorder at all three ages. The association was stronger for women and remained after adjusting for prior disorder. For women reporting 2.5 or more partners per year, compared to 0-1 partners, the adjusted odd ratios (and 95 % CIs) were 9.6 (4.4-20.9), 7.3 (2.5-21.3), and 17.5 (3.5-88.1) at 21, 26, and 32 years, respectively. Analyses using new cases of these disorders showed similar patterns. This study established a strong association between number of sex partners and later substance disorder, especially for women, which persisted beyond prior substance use and mental health problems more generally. The reasons for this association deserve investigation.

The association between racial disparity in income and reported sexually transmitted infections

OBJECTIVES

We examined the association between racial disparity in income and reported race-specific county-level bacterial sexually transmitted infections (STIs) in the United States focusing on disparities between Blacks and Whites.

METHODS

Data are from the US 2000 decennial census. We defined 2 race-income county groups (high and low race-income disparity) on the basis of the difference between Black and White median household incomes. We used 2 approaches to examine disparities in STI rates across the groups. In the first approach, we computed and compared race-specific STI rates for the groups. In the second approach, we used spatial regression analyses to control for potential confounders.

RESULTS

Consistent with the STI literature, chlamydia, gonorrhea, and syphilis rates for Blacks were substantially higher than were those for Whites. We also found that racial disparities in income were associated with racial disparities in chlamydia and gonorrhea rates and, to a lesser degree, syphilis rates.

CONCLUSIONS

Racial disparities in household income may be a more important determinant of racial disparities in reported STI morbidity than are absolute levels of household income.

Rising popularity of anal intercourse and sexual risk taking: findings from two national probability studies of young Croatian adults

This study examined the prevalence and correlates of heterosexual anal intercourse in two national probability samples of young Croatian adults aged 18–25 years, which were collected in 2005 and 2010. The lifetime prevalence of anal intercourse increased from 27% to 36%. In multivariate analysis, reporting four or more lifetime sexual partners was the only correlate of the experience of anal intercourse that was significant among both women (odds ratios [ORs] = 1.78–3.27, P < 0.05) and men (ORs = 3.14–4.63, P < 0.01). Information about condom use at most recent anal intercourse was collected in the 2010 study wave only. Age (OR = 0.80, P < 0.05), female gender (OR = 0.29, P < 0.01), holding more negative attitudes towards condoms (OR = 0.28–0.32, P < 0.05) and reporting condom use at most recent vaginal intercourse (OR = 11.45, 95% Confidence interval [CI] = 5.68–23.06) were associated with using a condom at most recent anal intercourse. Given the substantial prevalence of anal intercourse among young heterosexual adults and considerable sexually transmitted infection/HIV risks associated with the practice, sex education programmes should promote the discussion of health risks associated with anal eroticism.

Local public health systems and the incidence of sexually transmitted diseases

OBJECTIVES

We examined the associations of local public health system organization and local health department resources with county-level sexually transmitted disease (STD) incidence rates in large US health jurisdictions.

METHODS

We linked annual county STD incidence data (2005-2008) to local health department director responses (n = 211) to the 2006 wave of the National Longitudinal Study of Local Public Health Systems, the 2005 national Local Health Department Profile Survey, and the Area Resource File. We used nested mixed effects regression models to assess the relative contribution of local public health system organization, local health department financial and resource factors, and sociodemographic factors known to be associated with STD incidence to county-level (n = 307) STD incidence.

RESULTS

Jurisdictions with local governing boards had significantly lower county-level STD incidence. Local public health systems with comprehensive services where local health departments shoulder much of the effort had higher county-level STD rates than did conventional systems.

CONCLUSIONS

More integration of system partners in local public health system activities, through governance and interorganizational arrangements, may reduce the incidence and burden of STDs.

Consistency and reliability of self-reported lifetime number of heterosexual partners by gender and age in a cohort study

BACKGROUND

The reported number of sexual partners is a variable used extensively in sexual health research. However, the reliability and consistency of this measure, and the statistical assessment of these attributes, are not well understood.

METHODS

Using data at ages 21, 26, and 32 years from a New Zealand birth cohort, we compared responses on the lifetime number of heterosexual sex partners to assess reliability and consistency. Differences by gender and age were considered, and the effect of number of sexual partners. A variety of analytical methods were used to explore statistical challenges of these data including variance estimation, fractional polynomial transformations, and quantile regression.

RESULTS

We found some level of discrepancy between reports of the number of sexual partners when assessed at different times is common, driven by those reporting a high number of partners who were disproportionately men. Men reported a higher lifetime number of partners than women at each age, and there were statistically significant differences by gender in (a) consistency between reports at different ages, and (b) reliability of reports as measured by both the Intraclass Correlation Coefficient and the Kappa statistic.

CONCLUSIONS

When considering reliability, multiple statistical approaches are necessary or conclusions can be misleading. Variance components should be examined when considering the Intraclass Correlation Coefficient. When modelling, robust methods like fractional polynomials and quantile regression should be employed to accommodate nonlinearity. Sensitivity analyses excluding participants whose partner number is in the upper 5% to 25% are informative, as these were shown to have the highest discrepancies.

Factors associated with event level anal sex and condom use during anal sex among adolescent women

PURPOSE

To examine the distribution of and factors associated with event-level heterosexual anal sex and of event-level condom use during anal sex among adolescent women.

METHODS

Adolescent women (N=387; age 14-17 years at enrollment) were recruited from primary care clinics for a longitudinal cohort study of sexually transmitted infections and sexual behavior. Data were taken from daily sexual diaries; generalized estimating equation logistic regression assessed the likelihood of anal sex or condom use during anal sex on a given day.

RESULTS

Heterosexual anal intercourse is a small but nonrandom event-level component in adolescent women's sexual behavior. About 30% of anal sex events were condom protected. Mood, partner, and situational factors predicted anal sex, but not condom use during anal sex; within-day and recent behavior factors were the strongest influences on both outcomes.

CONCLUSIONS

Our findings suggest the importance of providers' screening adolescent women patients during office visits about anal sex and about condom use during anal sex, as well as asking questions about the context of these behaviors to appropriately tailor risk reduction counseling.

Using spatial regression methods to examine the association between county-level racial/ethnic composition and reported cases of Chlamydia and gonorrhea: an illustration with data from the state of Texas

BACKGROUND

Several studies have reported racial/ethnic disparities in the incidence of sexually transmitted diseases. However, very few studies have accounted for potential spatial dependence. Additionally, little is known about the relative magnitudes of the associations between county-level racial/ethnic composition and the 2 most commonly reported sexually transmitted diseases.

METHODS

We used county-level data from the National Electronic Telecommunications System for Surveillance and the 2000 Census data to investigate the association between county-level racial/ethnic composition and reported cases of the 2 most commonly reported sexually transmitted diseases (chlamydia and gonorrhea) in Texas. We also estimated ordinary least square (OLS) models for comparison.

RESULTS

Preliminary results from the spatial regression models indicated that the choice of spatial relationships criteria was important for model specification. The spatial error model (SEM) was superior to the spatial autoregressive model, spatial Durbin model, and OLS. The SEM for the 2 disease equations were further analyzed using a seemingly unrelated regression estimation (SURE) procedure. Although the SEM was superior to all models (using standard criteria), the coefficients were fairly stable across models. Our results showed that a unit change in percent black was associated with 1.6 (1.1 for Hispanic) and 3.3 (0.5 for Hispanic) percent change in chlamydia and gonorrhea rates (on average), respectively, compared with percent white.

CONCLUSION

Although there were no substantial differences in the magnitude of the estimated parameters, spatial regression models are potentially superior to OLS models and should be explored in future sexually transmitted disease studies.

Unlinked anonymous HIV prevalence among New Zealand sexual health clinic attenders: 2005-2006

This unlinked anonymous study aimed at determining the prevalence of HIV among sexual health clinic attenders having blood samples taken for syphilis and/or hepatitis B serology in six major New Zealand cities over a 12-month period in 2005-2006. Overall, seroprevalence was five per 1000 (47/9439). Among men who have sex with men (MSM), the overall prevalence and that of previously undiagnosed HIV were 44.1 and 20.1 per 1000, respectively. In heterosexual men, the overall prevalence was 1.2 per 1000 and in women 1.4 per 1000. HIV remains to be concentrated among homosexual and bisexual men. Comparison with a previous survey in 1996-1997 suggests an increase in the prevalence of undiagnosed HIV among MSM and also an increase in the number of MSM attending sexual health clinics. The low prevalence of HIV among heterosexuals suggests no extensive spread into the groups identified at risk of other sexually transmitted infections.

Social discrimination, concurrent sexual partnerships, and HIV risk among men who have sex with men in Shanghai, China

We examined the potential mediating role of sex partner concurrency in explaining associations between experiences of homophobia and financial hardship and HIV risk behavior among a sample of 477 men who have sex with men (MSM) recruited in Shanghai, China from 2004 to 2005. We found significant positive direct associations of experiences of homophobia and financial hardship with having unprotected anal sex with men. These associations were not mediated by male partner concurrency. However, male partner concurrency had a direct effect on having unprotected anal sex with men. Male and female partner concurrency did not mediate the significant association between experiences of homophobia and having unprotected anal/vaginal sex with both men and women, but was positively associated with having unprotected anal/vaginal sex with both men and women. These results suggest that homophobia, financial hardship, and sex partner concurrency should be addressed to help reduce sexual risk for HIV among MSM in China.