Sevgi Aral - Academia.edu (original) (raw)

Papers by Sevgi Aral

n overwhelming majority of the global burden of morbidity and mortality caused by sexually trans-... more n overwhelming majority of the global burden of morbidity and mortality caused by sexually trans-mitted infections (STI) and HIV is borne by the world’s poorest countries (fig 1). In a world increasingly ‘‘shrunk’ ’ by modern communications, what are the common issues preoccupying the international community of researchers in our field? In planning this themed issue, published on World AIDS Day 2007, we sought papers on all topics of global relevance: migration, international travel, the extent and impact of antiretroviral rollout pro-grammes, and wide-reaching strategies

Poster Presentations, 2019

JAIDS Journal of Acquired Immune Deficiency Syndromes, 2018

on behalf of the Transitions Study Team Background: Adolescent girls and young women (AGYW) exper... more on behalf of the Transitions Study Team Background: Adolescent girls and young women (AGYW) experience high rates of HIV early in their sexual life course. We estimated the prevalence of HIV-associated vulnerabilities at first sex, and their association with lifetime gender-based violence (GBV) and HIV. Methods: We conducted a cross-sectional biobehavioral survey among AGYW (14-24 years) in Mombasa, Kenya in 2015. We compared the prevalence of first sex vulnerabilities across AGYW who self-identified as engaging in sex work (N = 408), transactional sex (N = 177), or casual sex (N = 714) and used logistic regression to identify age-adjusted associations between first sex vulnerabilities and outcomes (GBV after first sex; HIV). Results: The median age at first sex was 16 years (interquartile range 14-18). A total of 43.6% received gifts or money at first sex; 41.2% and 11.2% experienced a coerced and forced first sex, respectively. First sex vulnerabilities were generally more common among AGYW in sex work. GBV (prevalence 23.8%) and HIV (prevalence 5.6%) were associated with first sex before age 15 [GBV adjusted odds ratio (AOR) 1.4, 95% confidence interval (CI):

Focus (San Francisco, Calif.), 2010

Public health reports (Washington, D.C. : 1974)

Sexually transmitted diseases (STD) are more prevalent among some minority populations in the Uni... more Sexually transmitted diseases (STD) are more prevalent among some minority populations in the United States than they are among the white majority. Primary and secondary syphilis occurs 45 times as often among non-Hispanic blacks as among non-Hispanic whites and 13 times as often among Hispanics as among non-Hispanic whites, according to morbidity reports received in 1988 by the Centers for Disease Control. Gonorrhea is reported more commonly among some minorities, with 1988 rates per 100,000 population being 54 for whites, 1,801 for blacks, and 201 for Hispanics. The reasons for the higher incidence of STD among some minorities are unknown. Data on racial differences in behavior and disease susceptibility are meager and do not account for the observed differences. Poverty, which is more common among some minorities than among the white majority, is closely associated with the prevalence of STD and may be a link between membership in a minority population and an increased risk.

Social Science & Medicine, 2007

We conducted spatial regression analysis to account for spatial clustering of sexually transmitte... more We conducted spatial regression analysis to account for spatial clustering of sexually transmitted diseases (STDs) and to examine the state-level association between social capital (using Putnam's public use data set) and rates of gonorrhea and syphilis. We conducted the analysis for the 48 contiguous states of the United States for 1990, 1995, and 2000 and controlled for the effects of regional variation in STD rates, and for state variation in poverty, income inequality, racial composition, and percentage aged 15-34 years. We compared the results of the spatial regression analysis with those of ordinary least squares (OLS) regression. Controlling for all population-level variables, the percentage of variation explained by the OLS regression and by the spatial regression were similar (mid-90s for gonorrhea and low-70s for syphilis), the standardized parameter estimates were similar, and the spatial lag parameter was not statistically significant. Social capital was not associated with STD rates when state variation in racial composition was included in the regression analysis. In this analysis, states with a higher proportion of residents who were African-American had higher STD rates. When we did not control for racial composition, regression analysis showed that states with higher social capital had lower STD rates. We conjecture that sexual networks and sexual mixing drive the association between social capital and STD rates and highlight important measurement and research questions that need elucidation to understand fully the relationship between social capital and STDs.

Sexually Transmitted Infections, 2006

Sexually Transmitted Infections, 2002

Sexually Transmitted Infections, 2010

Background and objectives Understanding the time course of sexual partnerships is important for u... more Background and objectives Understanding the time course of sexual partnerships is important for understanding sexual behaviour, transmission risks for sexually transmitted infections (STI) and development of mathematical models of disease transmission. Study design The authors describe issues and biases relating to censoring, truncation and sampling that arise when estimating partnership duration. Recommendations for study design and analysis methods are presented and illustrated using data from a sexual-behaviour survey that enrolled individuals from an adolescent-health clinic and two STD clinics. Survey participants were queried, for each of (up to) four partnerships in the last 3 months, about the month and year of first sex, the number of days since last sex and whether partnerships were limited to single encounters. Participants were followed every 4 months for up to 1 year. Results After adjustment for censoring and truncation, the estimated median duration of sexual partnerships declined from 9 months (unadjusted) to 1.6 months (adjusted). Similarly, adjustment for censoring and truncation reduced the bias in relative risks for the effect of age in a Cox model. Other approaches, such as weighted estimation, also reduced bias in the estimated duration distribution. Conclusion Methods are available for estimating partnership duration from censored and truncated samples. Ignoring censoring, truncation and other sampling issues results in biased estimates.

Sexually Transmitted Infections, 2006

Sexually Transmitted Infections, 2005

Sexually Transmitted Infections, 2013

Sexually Transmitted Infections, 2003

Background: Key strategies advocated for lowering personal risk of sexual exposure to STD/HIV inc... more Background: Key strategies advocated for lowering personal risk of sexual exposure to STD/HIV include having fewer partners and avoiding risky partners. However, few studies have systematically examined how well people can actually discern their sex partners' risk behaviours. Methods: We conducted face to face interviews with 151 heterosexual patients with gonorrhoea or chlamydial infection and 189 of their sex partners. Interviews examined the patients' perceptions of their sex partners' sociodemographic characteristics and risk behaviours. Patients' perceptions of partners were then sociometrically compared for agreement with partner self reports, using the kappa statistic for discrete variables and concordance correlation for continuous variables. Results: Agreement was highest for perceived partner age, race/ethnicity, and duration of sexual partnership; and lowest for knowledge of partner's work in commercial sex, number of other sex partners, and for perceived quality of communication within the partnership. Index patients commonly underestimated or overestimated partners' risk characteristics. Reported condom use was infrequent and inconsistent within partnerships. Conclusion: Among people with gonorrhoea or chlamydial infection, patients' perceptions of partners' risk behaviours often disagreed with the partners' self reports. Formative research should guide development and evaluation of interventions to enhance sexual health communication within partnerships and within social networks, as a potential harm reduction strategy to foster healthier partnerships.

Sexual Health, 2013

Background Numerous social determinants of health are associated with violent crime rates and sex... more Background Numerous social determinants of health are associated with violent crime rates and sexually transmissible infection (STI) rates. This report aims to illustrate the potential usefulness of violent crime rates as a proxy for the social determinants of STI rates. Methods: For each year from 1981 to 2010, we assessed the strength of the association between the violent crime rate and the gonorrhoea (Neisseria gonorrhoeae) rate (number of total reported cases per 100 000) at the state level. Specifically, for each year, we calculated Pearson correlation coefficients (and P-values) between two variables (the violent crime rate and the natural log of the gonorrhoea rate) for all 50 states and Washington, DC. For comparison, we also examined the correlation between gonorrhoea rates, and rates of poverty and unemployment. We repeated the analysis using overall syphilis rates instead of overall gonorrhoea rates. Results: The correlation between gonorrhoea and violent crime was signi...

Journal of Infectious Diseases, 1996

Each sexually transmitted disease (STD) epidemic evolves through predictable phases, shaped by a ... more Each sexually transmitted disease (STD) epidemic evolves through predictable phases, shaped by a dynamic interplay among the pathogen, the behaviors of the subpopulations in which it emerges, and the prevention efforts that are developed to limit its impact. As STD epidemics move through these phases, the sexual and social networks that fuel them become located in subpopulations characterized by progressively higher rates of sex partner change and less contact with the health care system. As a result, phase-appropriate prevention strategies and research issues are essential to reducing STDs and their consequences. The fundamental challenge to all prevention programs is to introduce into highly complex, dynamic, and inherently chaotic systems combinations of effective interventions that synergistically limit the spread and impact of disease, particularly among those groups most severely affected. Prevention programs addressing sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection, face additionally a unique challenge. They must modulate factors that define the interface between human populations and communicable pathogens-pathogens that have been sufficiently diabolical to link: their transmission to an act that is essential to survival of the human species, sex. An understanding of transmission-the interplay between continuously evolving STD pathogens and equally dynamic human behaviors-must guide the development of effective STD prevention programs. The "core group" has, for almost 2 decades, been a central pillar of our conceptual framework for the epidemiology of STD transmission within populations and hence, at least theoretically, for the targeting of programmatic interventions. This concept postulates the existence of an epidemiologic "bull's-eye" for prevention programs in that it suggests that all endemic and epidemic transmission of curable STDs is, in fact, sustained by small subsets of the population. Introduced in 1978 by Yorke et a1. [1] in considering the epidemiology of gonorrhea, the core group concept synthesized key biologic and behavioral characteristics of STD transmission, such as the fact that only sexually active persons are at risk, that infectiousness may persist for extended periods (both because of the natural history of these diseases and because of the high prevalence of asymptomatic infection), that bacterial STDs rarely generate a solidly protective immune response, and that sexual behavior is heterogeneous within populations.

Journal of Infectious Diseases, 1996

JAIDS Journal of Acquired Immune Deficiency Syndromes, 2013

Little is known about national trends in sexual behavior among MSM in the U.S. Data from the 2002... more Little is known about national trends in sexual behavior among MSM in the U.S. Data from the 2002 and 2006-10 National Survey of Family Growth were used to compare sexual behaviors of sexually active MSM. Mean number of recent male partners significantly decreased from 2.9 in 2002 to 2.1 in 2006-10 (p=.027), particularly among young MSM. Other sexual risk behaviors did not change or decreased over time. Our findings that sexual risk decreased as HIV and syphilis increased among MSM suggest that factors in addition to individual-level sexual risk should also be examined in relation to recent disease increases.

American Journal of Public Health, 2007

American Journal of Public Health, 1999

If you haven't already tested for radon, do so now. If your indoor radon level exceeds the guidan... more If you haven't already tested for radon, do so now. If your indoor radon level exceeds the guidance level, remediate. Ifyou have remediated, maintain your system properly and seek advice from local and state health officials as to how frequently retesting is warranted to ensure continued acceptable levels.

n overwhelming majority of the global burden of morbidity and mortality caused by sexually trans-... more n overwhelming majority of the global burden of morbidity and mortality caused by sexually trans-mitted infections (STI) and HIV is borne by the world’s poorest countries (fig 1). In a world increasingly ‘‘shrunk’ ’ by modern communications, what are the common issues preoccupying the international community of researchers in our field? In planning this themed issue, published on World AIDS Day 2007, we sought papers on all topics of global relevance: migration, international travel, the extent and impact of antiretroviral rollout pro-grammes, and wide-reaching strategies

Poster Presentations, 2019

JAIDS Journal of Acquired Immune Deficiency Syndromes, 2018

on behalf of the Transitions Study Team Background: Adolescent girls and young women (AGYW) exper... more on behalf of the Transitions Study Team Background: Adolescent girls and young women (AGYW) experience high rates of HIV early in their sexual life course. We estimated the prevalence of HIV-associated vulnerabilities at first sex, and their association with lifetime gender-based violence (GBV) and HIV. Methods: We conducted a cross-sectional biobehavioral survey among AGYW (14-24 years) in Mombasa, Kenya in 2015. We compared the prevalence of first sex vulnerabilities across AGYW who self-identified as engaging in sex work (N = 408), transactional sex (N = 177), or casual sex (N = 714) and used logistic regression to identify age-adjusted associations between first sex vulnerabilities and outcomes (GBV after first sex; HIV). Results: The median age at first sex was 16 years (interquartile range 14-18). A total of 43.6% received gifts or money at first sex; 41.2% and 11.2% experienced a coerced and forced first sex, respectively. First sex vulnerabilities were generally more common among AGYW in sex work. GBV (prevalence 23.8%) and HIV (prevalence 5.6%) were associated with first sex before age 15 [GBV adjusted odds ratio (AOR) 1.4, 95% confidence interval (CI):

Focus (San Francisco, Calif.), 2010

Public health reports (Washington, D.C. : 1974)

Sexually transmitted diseases (STD) are more prevalent among some minority populations in the Uni... more Sexually transmitted diseases (STD) are more prevalent among some minority populations in the United States than they are among the white majority. Primary and secondary syphilis occurs 45 times as often among non-Hispanic blacks as among non-Hispanic whites and 13 times as often among Hispanics as among non-Hispanic whites, according to morbidity reports received in 1988 by the Centers for Disease Control. Gonorrhea is reported more commonly among some minorities, with 1988 rates per 100,000 population being 54 for whites, 1,801 for blacks, and 201 for Hispanics. The reasons for the higher incidence of STD among some minorities are unknown. Data on racial differences in behavior and disease susceptibility are meager and do not account for the observed differences. Poverty, which is more common among some minorities than among the white majority, is closely associated with the prevalence of STD and may be a link between membership in a minority population and an increased risk.

Social Science & Medicine, 2007

We conducted spatial regression analysis to account for spatial clustering of sexually transmitte... more We conducted spatial regression analysis to account for spatial clustering of sexually transmitted diseases (STDs) and to examine the state-level association between social capital (using Putnam's public use data set) and rates of gonorrhea and syphilis. We conducted the analysis for the 48 contiguous states of the United States for 1990, 1995, and 2000 and controlled for the effects of regional variation in STD rates, and for state variation in poverty, income inequality, racial composition, and percentage aged 15-34 years. We compared the results of the spatial regression analysis with those of ordinary least squares (OLS) regression. Controlling for all population-level variables, the percentage of variation explained by the OLS regression and by the spatial regression were similar (mid-90s for gonorrhea and low-70s for syphilis), the standardized parameter estimates were similar, and the spatial lag parameter was not statistically significant. Social capital was not associated with STD rates when state variation in racial composition was included in the regression analysis. In this analysis, states with a higher proportion of residents who were African-American had higher STD rates. When we did not control for racial composition, regression analysis showed that states with higher social capital had lower STD rates. We conjecture that sexual networks and sexual mixing drive the association between social capital and STD rates and highlight important measurement and research questions that need elucidation to understand fully the relationship between social capital and STDs.

Sexually Transmitted Infections, 2006

Sexually Transmitted Infections, 2002

Sexually Transmitted Infections, 2010

Background and objectives Understanding the time course of sexual partnerships is important for u... more Background and objectives Understanding the time course of sexual partnerships is important for understanding sexual behaviour, transmission risks for sexually transmitted infections (STI) and development of mathematical models of disease transmission. Study design The authors describe issues and biases relating to censoring, truncation and sampling that arise when estimating partnership duration. Recommendations for study design and analysis methods are presented and illustrated using data from a sexual-behaviour survey that enrolled individuals from an adolescent-health clinic and two STD clinics. Survey participants were queried, for each of (up to) four partnerships in the last 3 months, about the month and year of first sex, the number of days since last sex and whether partnerships were limited to single encounters. Participants were followed every 4 months for up to 1 year. Results After adjustment for censoring and truncation, the estimated median duration of sexual partnerships declined from 9 months (unadjusted) to 1.6 months (adjusted). Similarly, adjustment for censoring and truncation reduced the bias in relative risks for the effect of age in a Cox model. Other approaches, such as weighted estimation, also reduced bias in the estimated duration distribution. Conclusion Methods are available for estimating partnership duration from censored and truncated samples. Ignoring censoring, truncation and other sampling issues results in biased estimates.

Sexually Transmitted Infections, 2006

Sexually Transmitted Infections, 2005

Sexually Transmitted Infections, 2013

Sexually Transmitted Infections, 2003

Background: Key strategies advocated for lowering personal risk of sexual exposure to STD/HIV inc... more Background: Key strategies advocated for lowering personal risk of sexual exposure to STD/HIV include having fewer partners and avoiding risky partners. However, few studies have systematically examined how well people can actually discern their sex partners' risk behaviours. Methods: We conducted face to face interviews with 151 heterosexual patients with gonorrhoea or chlamydial infection and 189 of their sex partners. Interviews examined the patients' perceptions of their sex partners' sociodemographic characteristics and risk behaviours. Patients' perceptions of partners were then sociometrically compared for agreement with partner self reports, using the kappa statistic for discrete variables and concordance correlation for continuous variables. Results: Agreement was highest for perceived partner age, race/ethnicity, and duration of sexual partnership; and lowest for knowledge of partner's work in commercial sex, number of other sex partners, and for perceived quality of communication within the partnership. Index patients commonly underestimated or overestimated partners' risk characteristics. Reported condom use was infrequent and inconsistent within partnerships. Conclusion: Among people with gonorrhoea or chlamydial infection, patients' perceptions of partners' risk behaviours often disagreed with the partners' self reports. Formative research should guide development and evaluation of interventions to enhance sexual health communication within partnerships and within social networks, as a potential harm reduction strategy to foster healthier partnerships.

Sexual Health, 2013

Background Numerous social determinants of health are associated with violent crime rates and sex... more Background Numerous social determinants of health are associated with violent crime rates and sexually transmissible infection (STI) rates. This report aims to illustrate the potential usefulness of violent crime rates as a proxy for the social determinants of STI rates. Methods: For each year from 1981 to 2010, we assessed the strength of the association between the violent crime rate and the gonorrhoea (Neisseria gonorrhoeae) rate (number of total reported cases per 100 000) at the state level. Specifically, for each year, we calculated Pearson correlation coefficients (and P-values) between two variables (the violent crime rate and the natural log of the gonorrhoea rate) for all 50 states and Washington, DC. For comparison, we also examined the correlation between gonorrhoea rates, and rates of poverty and unemployment. We repeated the analysis using overall syphilis rates instead of overall gonorrhoea rates. Results: The correlation between gonorrhoea and violent crime was signi...

Journal of Infectious Diseases, 1996

Each sexually transmitted disease (STD) epidemic evolves through predictable phases, shaped by a ... more Each sexually transmitted disease (STD) epidemic evolves through predictable phases, shaped by a dynamic interplay among the pathogen, the behaviors of the subpopulations in which it emerges, and the prevention efforts that are developed to limit its impact. As STD epidemics move through these phases, the sexual and social networks that fuel them become located in subpopulations characterized by progressively higher rates of sex partner change and less contact with the health care system. As a result, phase-appropriate prevention strategies and research issues are essential to reducing STDs and their consequences. The fundamental challenge to all prevention programs is to introduce into highly complex, dynamic, and inherently chaotic systems combinations of effective interventions that synergistically limit the spread and impact of disease, particularly among those groups most severely affected. Prevention programs addressing sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection, face additionally a unique challenge. They must modulate factors that define the interface between human populations and communicable pathogens-pathogens that have been sufficiently diabolical to link: their transmission to an act that is essential to survival of the human species, sex. An understanding of transmission-the interplay between continuously evolving STD pathogens and equally dynamic human behaviors-must guide the development of effective STD prevention programs. The "core group" has, for almost 2 decades, been a central pillar of our conceptual framework for the epidemiology of STD transmission within populations and hence, at least theoretically, for the targeting of programmatic interventions. This concept postulates the existence of an epidemiologic "bull's-eye" for prevention programs in that it suggests that all endemic and epidemic transmission of curable STDs is, in fact, sustained by small subsets of the population. Introduced in 1978 by Yorke et a1. [1] in considering the epidemiology of gonorrhea, the core group concept synthesized key biologic and behavioral characteristics of STD transmission, such as the fact that only sexually active persons are at risk, that infectiousness may persist for extended periods (both because of the natural history of these diseases and because of the high prevalence of asymptomatic infection), that bacterial STDs rarely generate a solidly protective immune response, and that sexual behavior is heterogeneous within populations.

Journal of Infectious Diseases, 1996

JAIDS Journal of Acquired Immune Deficiency Syndromes, 2013

Little is known about national trends in sexual behavior among MSM in the U.S. Data from the 2002... more Little is known about national trends in sexual behavior among MSM in the U.S. Data from the 2002 and 2006-10 National Survey of Family Growth were used to compare sexual behaviors of sexually active MSM. Mean number of recent male partners significantly decreased from 2.9 in 2002 to 2.1 in 2006-10 (p=.027), particularly among young MSM. Other sexual risk behaviors did not change or decreased over time. Our findings that sexual risk decreased as HIV and syphilis increased among MSM suggest that factors in addition to individual-level sexual risk should also be examined in relation to recent disease increases.

American Journal of Public Health, 2007

American Journal of Public Health, 1999

If you haven't already tested for radon, do so now. If your indoor radon level exceeds the guidan... more If you haven't already tested for radon, do so now. If your indoor radon level exceeds the guidance level, remediate. Ifyou have remediated, maintain your system properly and seek advice from local and state health officials as to how frequently retesting is warranted to ensure continued acceptable levels.