Spatial distribution of HIV prevalence and incidence among injection drugs users in St Petersburg: implications for HIV transmission

Area-based comparison of risk factors and testing rates to improve sexual health care access: cross-sectional population-based study in a Dutch multicultural area

OBJECTIVES

Areas with high sexually transmitted infection (STI) testing rates may not require additional strategies to improve testing. However, it may be necessary to intervene in areas with elevated STI risk, but with low STI testing rates. We aimed to compare STI-related risk profiles and STI testing rates by geographical area to determine areas for improvement of sexual healthcare access.

DESIGN

Cross-sectional population-based study.

SETTING

Greater Rotterdam area, the Netherlands (2015-2019).

PARTICIPANTS

All residents aged 15-45 years. Individual population-based register data were matched with laboratory-based STI testing data of general practitioners (GPs) and the only sexual health centre (SHC).

OUTCOME MEASURES

Postal code (PC) area-specific STI risk scores (based on age, migratory background, education level and urbanisation), STI testing rates and STI positivity.

RESULTS

The study area consists of approximately 500 000 residents aged 15-45 years. Strong spatial variation in STI testing, STI positivity and STI risk was observed. PC area testing rate ranged from 5.2 to 114.9 tests per 1000 residents. Three PC clusters were identified based on STI risk and testing rate: (1) high-high; (2) high-low; (3) low, independently of testing rate. Clusters 1 and 2 had comparable STI-related risk and STI positivity, but the testing rate differed greatly (75.8 vs 33.2 per 1000 residents). Multivariable logistic regression analysis with generalised estimating equation was used to compare residents in cluster 1 and cluster 2. Compared with cluster 1, residents in cluster 2 more often did not have a migratory background, lived in less urbanised areas with higher median household income, and more distant from both GP and SHC.

CONCLUSION

The determinants associated with individuals living in areas with high STI-related risk scores and low testing rates provide leads for improvement of sexual healthcare access. Opportunities for further exploration include GP education, community-based testing and service (re)allocation.

Molecular Surveillance of HIV-1 Infection in Krasnoyarsk Region, Russia: Epidemiology, Phylodynamics and Phylogeography

BACKGROUND

The information about the dynamics of the viral population and migration events that affect the epidemic in different parts of the Russia is insufficient. Possibly, the huge size of the country and limited transport accessibility to certain territories may determine unique traits of the HIV-1 evolutionary history in different regions.

OBJECTIVE

The aim of this study was to explore the genetic diversity of HIV-1 in the Krasnoyarsk region and reconstruct spatial-temporal dynamics of the infection in the region.

METHODS

The demographic and virologic data from 281 HIV-infected individuals in Krasnoyarsk region collected during 2011-2016 were analyzed. The time to the most recent common ancestor, evolutionary rates, population growth, and ancestral geographic movements was estimated using Bayesian coalescent-based methods.

RESULTS

The study revealed moderate diversity of the HIV-1 subtypes found in the region, which included A6 (92.3%), CRF063_02A (4.3%), B (1.1%), and unique recombinants (2.5%). Phylogenetic reconstruction revealed that the A6 subtype was introduced into Krasnoyarsk region by one viral lineage, which arose around 1996.9 (1994.5-1999.5). The phylogeography analysis pointed to Krasnoyarsk city as the geographical center of the epidemic, which further spread to central neighboring districts of the region. At least two epidemic growth phases of subtype A6 were identified which included exponential growth in early-2000s followed by the decline in the mid/late 2010s.

CONCLUSION

This study demonstrates a change in the genetic diversity of HIV-1 in the Krasnoyarsk region. At the beginning of the epidemic, subtype A6 prevailed, subtypes B and CRF063_02A appeared in the region later.

Applying core theory and spatial analysis to identify hepatitis C virus infection "core areas" in British Columbia, Canada

"Core areas" of transmission for bacterial sexually transmitted infections have been identified. However, it is unclear whether core areas apply to viral infections, such as hepatitis C virus (HCV). We used geographic mapping and spatial analysis to identify distinct core areas of HCV infection in British Columbia (BC) using the BC Hepatitis Testers Cohort (BC-HTC), 1990-2013. The BC-HTC includes all BC residents tested for HCV (~1.5 million; 1990-2013). Core HCV infection areas were identified spatially and temporally for five time periods (1990-1993, 1994-1998, 1999-2003, 2004-2008 and 2009-2013) through thematic mapping, Kernel Density Estimation, Hotspot analysis and cluster analysis at the Census dissemination area level in ArcGIS and SatScan. HCV infection core areas were consistently identified. HCV core areas expanded from the downtown of major cities in different regions of BC (Metro Vancouver, Vancouver Island, and Northern BC; 1990-1998), to smaller cities in Metro Vancouver and Interior BC (2000 onwards). Statistically significant clusters, or hotspots, were also observed for downtown Vancouver, Northern BC (Prince George) and Vancouver Island from 1990 to 2008 with expansion to other urban areas in Metro Vancouver from 1990-2013. Statistically significant clusters persisted after adjustment for injection drug use, number of HCV tests, age, sex, material and social deprivation. Persistence of areas with high HCV diagnoses rates in Vancouver and Prince George supports the theory of core areas of HCV transmission. Identification of core areas can inform prevention, care and treatment programme interventions and evaluate their impact over time.

The Human Immunodeficiency Virus Endemic: Maintaining Disease Transmission in At-Risk Urban Areas

OBJECTIVES

A study of network relationships, geographic contiguity, and risk behavior was designed to test the hypothesis that all 3 are required to maintain endemicity of human immunodeficiency virus (HIV) in at-risk urban communities. Specifically, a highly interactive network, close geographic proximity, and compound risk (multiple high-risk activities with multiple partners) would be required.

METHODS

We enrolled 927 participants from two contiguous geographic areas in Atlanta, GA: a higher-risk area and lower-risk area, as measured by history of HIV reporting. We began by enrolling 30 "seeds" (15 in each area) who were comparable in their demographic and behavioral characteristics, and constructed 30 networks using a chain-link design. We assessed each individual's geographic range; measured the network characteristics of those in the higher and lower-risk areas; and measured compound risk as the presence of two or more (of 6) major risks for HIV.

RESULTS

Among participants in the higher-risk area, the frequency of compound risk was 15%, compared with 5% in the lower-risk area. Geographic cohesion in the higher-risk group was substantially higher than that in the lower-risk group, based on comparison of geographic distance and social distance, and on the extent of overlap of personal geographic range. The networks in the 2 areas were similar: both areas show highly interactive networks with similar degree distributions, and most measures of network attributes were virtually the same.

CONCLUSIONS

Our original hypothesis was supported in part. The higher and lower-risk groups differed appreciably with regard to risk and geographic cohesion, but were substantially the same with regard to network properties. These results suggest that a "minimum" network configuration may be required for maintenance of endemic transmission, but a particular prevalence level may be determined by factors related to risk, geography, and possibly other factors.

Spatial distribution of HIV, HCV, and co-infections among drug users in the southwestern border areas of China (2004-2014): a cohort study of a national methadone maintenance treatment program

Background

A methadone maintenance treatment (MMT) program to curb the dual epidemics of HIV/AIDS and drug use has been administered by China since 2004. Little is known regarding the geographic heterogeneity of HIV and hepatitis C virus (HCV) infections among MMT clients in the resource-constrained context of Chinese provinces, such as Guangxi. This study aimed to characterize the geographic distribution patterns and co-clustered epidemic factors of HIV, HCV and co-infections at the county level among drug users receiving MMT in Guangxi Zhuang Autonomous Region, located in the southwestern border area of China.

Methods

Baseline data on drug users’ demographic, behavioral and biological characteristics in the MMT clinics of Guangxi Zhuang Autonomous Region during the period of March 2004 to December 2014 were obtained from national HIV databases. Residential addresses were entered into a geographical information system (GIS) program and analyzed for spatial clustering of HIV, HCV and co-infections among MMT clients at the county level using geographic autocorrelation analysis and geographic scan statistics.

Results

A total of 31,015 MMT clients were analyzed, and the prevalence of HIV, HCV and co-infections were 13.05%, 72.51% and 11.96% respectively. Both the geographic autocorrelation analysis and geographic scan statistics showed that HIV, HCV and co-infections in Guangxi Zhuang Autonomous Region exhibited significant geographic clustering at the county level, and the Moran’s I values were 0.33, 0.41 and 0.30, respectively (P < 0.05). The most significant high-risk overlapping clusters for these infections were restricted to within a 10.95 km² radius of each of the 13 locations where P county was the cluster center. These infections also co-clustered with certain characteristics, such as being unmarried, having a primary level of education or below, having used drugs for more than 10 years, and receptive sharing of syringes with others. The high-risk clusters for these characteristics were more likely to reside in the areas surrounding P county.

Conclusions

HIV, HCV and co-infections among MMT clients in Guangxi Zhuang Autonomous Region all presented substantial geographic heterogeneity at the county level with a number of overlapping significant clusters. The areas surrounding P county were effective in enrolling high-risk clients in their MMT programs which, in turn, might enable people who inject drugs to inject less, share fewer syringes, and receive referrals for HIV or HCV treatment in a timely manner.

Defining HIV-1 transmission clusters based on sequence data

Understanding HIV-1 transmission dynamics is relevant to both screening and intervention strategies of HIV-1 infection. Commonly, HIV-1 transmission chains are determined based on sequence similarity assessed either directly from a sequence alignment or by inferring a phylogenetic tree. This review is aimed at both nonexperts interested in understanding and interpreting studies of HIV-1 transmission, and experts interested in finding the most appropriate cluster definition for a specific dataset and research question. We start by introducing the concepts and methodologies of how HIV-1 transmission clusters usually have been defined. We then present the results of a systematic review of 105 HIV-1 molecular epidemiology studies summarizing the most common methods and definitions in the literature. Finally, we offer our perspectives on how HIV-1 transmission clusters can be defined and provide some guidance based on examples from real life datasets.

Rapid Decline in HIV Incidence Among Persons Who Inject Drugs During a Fast-Track Combination Prevention Program After an HIV Outbreak in Athens

Background

A "seek-test-treat" intervention (ARISTOTLE) was implemented in response to an outbreak of human immunodeficiency virus (HIV) infection among persons who inject drugs (PWID) in Athens. We assess trends in HIV incidence, prevalence, risk behaviors and access to prevention/treatment.

Methods

Methods included behavioral data collection, provision of injection equipment, HIV testing, linkage to opioid substitution treatment (OST) programs and HIV care during 5 rounds of respondent-driven sampling (2012-2013). HIV incidence was estimated from observed seroconversions.

Results

Estimated coverage of the target population was 88% (71%-100%; 7113 questionnaires/blood samples from 3320 PWID). The prevalence of HIV infection was 16.5%. The incidence per 100 person-years decreased from 7.8 (95% confidence interval, 4.6-13.1) (2012) to 1.7 (0.55-5.31) (2013; P for trend = .001). Risk factors for seroconversion were frequency of injection, homelessness, and history of imprisonment. Injection at least once daily declined from 45.2% to 18.8% (P < .001) and from 36.8% to 26.0% (P = .007) for sharing syringes, and the proportion of undiagnosed HIV infection declined from 84.3% to 15.0% (P < .001). Current OST increased from 12.2% to 27.7% (P < .001), and 48.4% of unlinked seropositive participants were linked to HIV care through 2013. Repeat participants reported higher rates of adequate syringe coverage, linkage to HIV care and OST.

Conclusions

Multiple evidence-based interventions delivered through rapid recruitment in a large proportion of the population of PWID are likely to have helped mitigate this HIV outbreak.

Triangulating Syndemic Services and Drug Treatment Policy: Improving Drug Treatment Portal Locations in Baltimore City

THE PROBLEM

The prevalence of injection drug use (IDU) and incidence of human immunodeficiency virus (HIV) remain high in Baltimore, where IDU is a primary HIV risk factor. Substance use disorders and HIV are related syndemically--their causes and consequences interact synergistically. Baltimore is increasingly considering the syndemic relationship of substance use disorders, IDU, and HIV in making decisions about drug treatment funding and location.

PURPOSE OF ARTICLE

Our goal was to empirically identify the optimal location of new drug treatment programs through the development and application of a novel, practical tool.

KEY POINTS

Syndemic triangles were constructed to measure and visualize unmet need for drug treatment services. These data were used to determine priority zones for new treatment centers.

CONCLUSIONS

The application of this tool helped inform strategies for locating drug treatment services in Baltimore, and its successful use suggests its potential value in other metropolitan areas.

Neighborhood-Level and Spatial Characteristics Associated with Lay Naloxone Reversal Events and Opioid Overdose Deaths

There were over 23,000 opioid overdose deaths in the USA in 2013, and opioid-related mortality is increasing. Increased access to naloxone, particularly through community-based lay naloxone distribution, is a widely supported strategy to reduce opioid overdose mortality; however, little is known about the ecological and spatial patterns of the distribution and utilization of lay naloxone. This study aims to investigate the neighborhood-level correlates and spatial relationships of lay naloxone distribution and utilization and opioid overdose deaths. We determined the locations of lay naloxone distribution sites and the number of unintentional opioid overdose deaths and reported reversal events in San Francisco census tracts (n = 195) from 2010 to 2012. We used Wilcoxon rank-sum tests to compare census tract characteristics across tracts adjacent and not adjacent to distribution sites and multivariable negative binomial regression models to assess the association between census tract characteristics, including distance to the nearest site, and counts of opioid overdose deaths and naloxone reversal events. Three hundred forty-two opioid overdose deaths and 316 overdose reversals with valid location data were included in our analysis. Census tracts including or adjacent to a distribution site had higher income inequality, lower percentage black or African American residents, more drug arrests, higher population density, more overdose deaths, and more reversal events (all p < 0.05). In multivariable analysis, greater distance to the nearest distribution site (up to a distance of 4000 m) was associated with a lower count of Naloxone reversals [incidence rate ratio (IRR) = 0.51 per 500 m increase, 95% CI 0.39-0.67, p < 0.001] but was not significantly associated with opioid overdose deaths. These findings affirm that locating lay naloxone distribution sites in areas with high levels of substance use and overdose risk facilitates reversals of opioid overdoses in those immediate areas but suggests that alternative delivery methods may be necessary to reach individuals in other areas with less concentrated risk.

Emergence of methadone as a street drug in St. Petersburg, Russia

BACKGROUND

The syndemic of opioid addiction, HIV, hepatitis, tuberculosis, imprisonment, and overdose in Russia has been worsened by the illegality of opioid substitution therapy. As part of on-going serial studies, we sought to explore the influence of opioid availability on aspects of the syndemic as it has affected the city of St. Petersburg.

METHODS

We employed a sequential approach in which quantitative data collection and statistical analysis were followed by a qualitative phase. Quantitative data were obtained in 2013-2014 from a respondent-driven sample (RDS) of people who inject drugs (PWID). Individuals recruited by RDS were tested for antibodies to HIV and interviewed about drug use and injection practices, sociodemographics, health status, and access to medical care. Subsequently, we collected in-depth qualitative data on methadone use, knowledge, and market availability from PWID recruited at nine different locations within St. Petersburg.

RESULTS

Analysis of interview data from the sample revealed the percentage of PWID injecting methadone in the 30 days prior to interview increased from 3.6% in 2010 to 53.3% in 2012-2013. Injection of only methadone, as compared to injecting only heroin or both drugs, was associated with less frequent injection and reduced HIV-related injected risk, especially a lower rate of injecting with a previously used syringe. In-depth questioning of methadone injectors corroborated the finding from serial quantitative surveys of PWID that methadone's black market availability is a recent phenomenon. Spatial analysis revealed widespread methadone availability but no concentration in any specific districts of the city.

CONCLUSION

Despite the prohibition of substitution therapy and demonization of methadone, the drug has emerged to rival heroin as the most commonly available opioid in St. Petersburg. Ironically, its use is associated with reduced injection-related HIV risk even when its use is illegal.

Assessing the geographic coverage and spatial clustering of illicit drug users recruited through respondent-driven sampling in New York City

We assess the geographic coverage and spatial clustering of drug users recruited through respondent-driven sampling (RDS) and discuss the potential for biased RDS prevalence estimates. Illicit drug users aged 18-40 were recruited through RDS (N = 401) and targeted street outreach (TSO) (N = 210) in New York City. Using the Google Maps API™, we calculated travel distances and times using public transportation between each participant's recruitment location and the study office and between RDS recruiter-recruit pairs. We used K function analysis to evaluate and compare spatial clustering of (1) RDS vs. TSO respondents and (2) RDS seeds vs. RDS peer recruits. All participant recruitment locations clustered around the study office; however, RDS participants were significantly more likely to be recruited within walking distance of the study office than TSO participants. The TSO sample was also less spatially clustered than the RDS sample, which likely reflects (1) the van's ability to increase the sample's geographic heterogeneity and (2) that more TSO than RDS participants were enrolled on the van. Among RDS participants, individuals recruited spatially proximal peers, geographic coverage did not increase as recruitment waves progressed, and peer recruits were not less spatially clustered than seeds. Using a mobile van to recruit participants had a greater impact on the geographic coverage and spatial dependence of the TSO than the RDS sample. Future studies should consider and evaluate the impact of the recruitment approach on the geographic/spatial representativeness of the sample and how spatial biases, including the preferential recruitment of proximal peers, could impact the precision and accuracy of estimates.

The AIDS epidemic and economic input impact factors in Chongqing, China, from 2006 to 2012: a spatial-temporal analysis

OBJECTIVE

To analyse the spatial-temporal clustering of the HIV/AIDS epidemic in Chongqing and to explore its association with the economic indices of AIDS prevention and treatment.

METHODS

Data on the HIV/AIDS epidemic and economic indices of AIDS prevention and treatment were obtained from the annual reports of the Chongqing Municipal Center for Disease Control for 2006-2012. Spatial clustering analysis, temporal-spatial clustering analysis, and spatial regression were used to conduct statistical analysis.

RESULTS

The annual average new HIV infection rate, incidence rate for new AIDS cases, and rate of people living with HIV in Chongqing were 5.97, 2.42 and 28.12 per 100,000, respectively, for 2006-2012. The HIV/AIDS epidemic showed a non-random spatial distribution (Moran's I≥0.310; p<0.05). The epidemic hotspots were distributed in the 15 mid-western counties. The most likely clusters were primarily located in the central region and southwest of Chongqing and occurred in 2010-2012. The regression coefficients of the total amount of special funds allocated to AIDS and to the public awareness unit for the numbers of new HIV cases, new AIDS cases, and people living with HIV were 0.775, 0.976 and 0.816, and -0.188, -0.259 and -0.215 (p<0.002), respectively.

CONCLUSIONS

The Chongqing HIV/AIDS epidemic showed temporal-spatial clustering and was mainly clustered in the mid-western and south-western counties, showing an upward trend over time. The amount of special funds dedicated to AIDS and to the public awareness unit showed positive and negative relationships with HIV/AIDS spatial clustering, respectively.

Spatial analysis of HIV positive injection drug users in San Francisco, 1987 to 2005

Spatial analyses of HIV/AIDS related outcomes are growing in popularity as a tool to understand geographic changes in the epidemic and inform the effectiveness of community-based prevention and treatment programs. The Urban Health Study was a serial, cross-sectional epidemiological study of injection drug users (IDUs) in San Francisco between 1987 and 2005 (N = 29,914). HIV testing was conducted for every participant. Participant residence was geocoded to the level of the United States Census tract for every observation in dataset. Local indicator of spatial autocorrelation (LISA) tests were used to identify univariate and bivariate Census tract clusters of HIV positive IDUs in two time periods. We further compared three tract level characteristics (% poverty, % African Americans, and % unemployment) across areas of clustered and non-clustered tracts. We identified significant spatial clustering of high numbers of HIV positive IDUs in the early period (1987-1995) and late period (1996-2005). We found significant bivariate clusters of Census tracts where HIV positive IDUs and tract level poverty were above average compared to the surrounding areas. Our data suggest that poverty, rather than race, was an important neighborhood characteristic associated with the spatial distribution of HIV in SF and its spatial diffusion over time.

Automated analysis of phylogenetic clusters

BACKGROUND

As sequence data sets used for the investigation of pathogen transmission patterns increase in size, automated tools and standardized methods for cluster analysis have become necessary. We have developed an automated Cluster Picker which identifies monophyletic clades meeting user-input criteria for bootstrap support and maximum genetic distance within large phylogenetic trees. A second tool, the Cluster Matcher, automates the process of linking genetic data to epidemiological or clinical data, and matches clusters between runs of the Cluster Picker.

RESULTS

We explore the effect of different bootstrap and genetic distance thresholds on clusters identified in a data set of publicly available HIV sequences, and compare these results to those of a previously published tool for cluster identification. To demonstrate their utility, we then use the Cluster Picker and Cluster Matcher together to investigate how clusters in the data set changed over time. We find that clusters containing sequences from more than one UK location at the first time point (multiple origin) were significantly more likely to grow than those representing only a single location.

CONCLUSIONS

The Cluster Picker and Cluster Matcher can rapidly process phylogenetic trees containing tens of thousands of sequences. Together these tools will facilitate comparisons of pathogen transmission dynamics between studies and countries.

Measuring HIV- and AIDS-related stigma and discrimination in Nicaragua: results from a community-based study

Psychometric properties of external HIV-related stigma and discrimination scales and their predictors were investigated. A cross-sectional community-based study was carried out among 520 participants using an ongoing health and demographic surveillance system in León, Nicaragua. Participants completed an 18-item HIV stigma scale and 19 HIV and AIDS discrimination-related statements. A factor analysis found that 15 of the 18 items in the stigma scale and 18 of the 19 items in the discrimination scale loaded clearly into five- and four-factor structures, respectively. Overall Cronbach's alpha of .81 for the HIV stigma scale and .91 for the HIV discrimination scale provided evidence of internal consistency. Hierarchical multiple linear regression analysis identified that females, rural residents, people with insufficient HIV-related transmission knowledge, those not tested for HIV, those reporting an elevated self-perception of HIV risk, and those unwilling to disclose their HIV status were associated with higher stigmatizing attitudes and higher discriminatory actions towards HIV-positive people. This is the first community-based study in Nicaragua that demonstrates that overall HIV stigma and discrimination scales were reliable and valid in a community-based sample comprised of men and women of reproductive age. Stigma and discrimination were reported high in the general population, especially among sub-groups. The findings in the current study suggest community-based strategies, including the monitoring of stigma and discrimination, and designing and implementing stigma reduction interventions, are greatly needed to reduce inequities and increase acceptance of persons with HIV.

Individual and neighborhood correlates of membership in drug using networks with a higher prevalence of HIV in New York City (2006-2009)

PURPOSE

To identify individual- and neighborhood-level correlates of membership within high HIV prevalence drug networks.

METHODS

We recruited 378 New York City drug users via respondent-driven sampling (2006-2009). Individual-level characteristics and recruiter-recruit relationships were ascertained and merged with 2000 tract-level U.S. Census data. Descriptive statistics and population average models were used to identify correlates of membership in high HIV prevalence drug networks (>10.54% vs. <10.54% HIV).

RESULTS

Individuals in high HIV prevalence drug networks were more likely to be recruited in neighborhoods with greater inequality (adjusted odds ratio [AOR], 5.85; 95% confidence interval [CI], 1.40-24.42), higher valued owner-occupied housing (AOR, 1.48; 95% CI, 1.14-1.92), and a higher proportion of Latinos (AOR, 1.83; 95% CI, 1.19-2.80). They reported more crack use (AOR, 7.23; 95% CI, 2.43-21.55), exchange sex (AOR, 1.82; 95% CI, 1.03-3.23), and recent drug treatment enrollment (AOR, 1.62; 95% CI, 1.05-2.50) and were less likely to report cocaine use (AOR, 0.40; 95% CI, 0.20-0.79) and recent homelessness (AOR, 0.32; 95% CI, 0.17-0.57).

CONCLUSIONS

The relationship between exchange sex, crack use, and membership within high HIV prevalence drug networks may suggest an ideal HIV risk target population for intervention. Coupling network-based interventions with those adding risk-reduction and HIV testing/care/adherence counseling services to the standard of care in drug treatment programs should be explored in neighborhoods with increased inequality, higher valued owner-occupied housing, and a greater proportion of Latinos.

Inebriation, drinking motivations and sexual risk taking among sexually transmitted disease clinic patients in St. Petersburg, Russia

We investigated whether inebriation was associated with having non-main partners and unprotected sex with non-main partners and whether drinking motivations were associated with sexual risk behaviors among patients attending an STD clinic in St Petersburg, Russia. A cross-sectional behavior survey was applied to 362 participants between 2008 and 2009. Multivariate logistic regression was used for analysis. At-risk drinking per Alcohol Use Disorders Identification Test (AUDIT-C) criteria (OR 2.5, 95% CI 1.4–4.4) was independently associated with having non-main sexual partners. Inebriation (OR 3.2, 95% CI 1.3–8.1) but not at-risk drinking or drinking prior to sex was associated with unprotected sex with non-main partners. Among drinkers, the consumption of alcohol to facilitate sexual encounters (OR 2.7, 95% CI 1.6–4.5) was associated with having non-main sexual partners. HIV prevention programs in Russia must address inebriation in addition to conventional patterns of problem drinking such as those measured by AUDIT-C and consider individuals’ motivations to drink that lead to sexual risk taking.

Geographic information system-based screening for TB, HIV, and syphilis (GIS-THIS): a cross-sectional study

OBJECTIVE

To determine the feasibility and case detection rate of a geographic information systems (GIS)-based integrated community screening strategy for tuberculosis, syphilis, and human immunodeficiency virus (HIV).

DESIGN

Prospective cross-sectional study of all participants presenting to geographic hot spot screenings in Wake County, North Carolina.

METHODS

The residences of tuberculosis, HIV, and syphilis cases incident between 1/1/05-12/31/07 were mapped. Areas with high densities of all 3 diseases were designated "hot spots." Combined screening for tuberculosis, HIV, and syphilis were conducted at the hot spots; participants with positive tests were referred to the health department.

RESULTS AND CONCLUSIONS

Participants (N = 247) reported high-risk characteristics: 67% previously incarcerated, 40% had lived in a homeless shelter, and 29% had a history of crack cocaine use. However, 34% reported never having been tested for HIV, and 41% did not recall prior tuberculin skin testing. Screening identified 3% (8/240) of participants with HIV infection, 1% (3/239) with untreated syphilis, and 15% (36/234) with latent tuberculosis infection. Of the eight persons with HIV, one was newly diagnosed and co-infected with latent tuberculosis; he was treated for latent TB and linked to an HIV provider. Two other HIV-positive persons had fallen out of care, and as a result of the study were linked back into HIV clinics. Of 27 persons with latent tuberculosis offered therapy, nine initiated and three completed treatment. GIS-based screening can effectively penetrate populations with high disease burden and poor healthcare access. Linkage to care remains challenging and will require creative interventions to impact morbidity.

Partner violence perpetration and victimization and HIV risk behaviors in St. Petersburg, Russia

Whether intimate partner violence (IPV) perpetration and victimization are associated with human immunodeficiency virus (HIV) risk behaviors is seldom investigated in Russia. The present study hypothesized that patients from a sexually transmitted infection center in Russia who perpetrated IPV or were victims of IPV would be more likely to have HIV risk behaviors including injection drug use, multiple partners, and inconsistent condom use than those who were not involved with IPV. We used a self-administered questionnaire to collect information from 381 patients on demographics, health status, injection drug use, sexual behaviors, and violence involving sexual partners between 2008 and 2009. After including sociodemographics, lifetime IPV perpetration was significantly associated with having had multiple sexual partners among male patients (odds ratio [OR] = 2.61, p < .05). IPV victimization was significantly associated with injection drug use among male and female patients (OR = 5.22, p < .05) and with inconsistent condom use among female patients (OR = 8.93, p < .05). IPV perpetration and victimization were common among male and female study participants and were associated with greater HIV risk behaviors. HIV prevention programs in Russia should address the risks associated with IPV among people at risk for HIV.

Double jeopardy--drug and sex risks among Russian women who inject drugs: initial feasibility and efficacy results of a small randomized controlled trial

BACKGROUND

With HIV prevalence estimated at 20% among female injecting drug users (IDUs) in St. Petersburg, Russia, there is a critical need to address the HIV risks of this at-risk population. This study characterized HIV risks associated with injecting drug use and sex behaviors and assessed the initial feasibility and efficacy of an adapted Woman-Focused intervention, the Women's CoOp, relative to a Nutrition control to reduce HIV risk behaviors among female IDUs in an inpatient detoxification drug treatment setting.

METHOD

Women (N = 100) were randomized into one of two one-hour long intervention conditions--the Woman-Focused intervention (n = 51) or a time and attention-matched Nutrition control condition (n = 49).

RESULTS

The results showed that 57% of the participants had been told that they were HIV-positive. At 3-month follow-up, both groups showed reduced levels of injecting frequency. However, participants in the Woman-Focused intervention reported, on average, a lower frequency of partner impairment at last sex act and a lower average number of unprotected vaginal sex acts with their main sex partner than the Nutrition condition.

CONCLUSION

The findings suggest that improvements in sexual risk reduction are possible for these at-risk women and that more comprehensive treatment is needed to address HIV and drug risks in this vulnerable population.

Estimates of HIV incidence among drug users in St. Petersburg, Russia: continued growth of a rapidly expanding epidemic

BACKGROUND

Russia has one of the world's fastest growing HIV epidemics and it has been largely concentrated among injection drug users (IDU). St Petersburg, Russia's second largest city, is one of the country's regions that has been most affected by the HIV epidemic. To monitor the current epidemic situation, we sought to estimate recent HIV incidence among IDU in St Petersburg.

METHODS

In a cross-sectional study of 691 IDU recruited during 2005-08, HIV incidence was estimated by two methods: a retrospective cohort analysis and BED capture enzyme immunoassay (EIA) results. Socio-demographic and behavioural correlates of incident infections and spatial patterns were examined.

RESULTS

In the retrospective cohort analysis, the incidence rate was estimated to be 14.1/100 person-years [95% confidence interval (CI) 10.7-17.6]. Using results of BED EIA and two correction formulas for known misclassification, incidence estimates were 23.9 (95% CI 17.8-30.1) and 25.5 (95% CI 18.9-32.0) per 100 person-years. Independent correlates of being recently infected included current unemployment (P = 0.004) and not having injected drugs in the past 30 days (P = 0.03). HIV incident cases were detected in all but one district in the city, with focal areas of transmission observed to be expanding.

CONCLUSIONS

High HIV incidence among IDU in St Petersburg attests to continued growth of the epidemic. The need for expansion of HIV prevention interventions targeted to vulnerable populations throughout the city is urgent. These results also suggest that the BED EIA may over-estimate incidence even after correction for low specificity.

Sexually transmitted disease core theory: roles of person, place, and time

The authors' purpose was to expand sexually transmitted disease core theory by examining the roles of person, place, and time in differentiating geographic core areas from outbreak areas. The authors mapped yearly census-tract-level syphilis rates for San Francisco, California, based on new primary and secondary syphilis cases reported to the San Francisco City sexually transmitted disease surveillance program between January 1, 1985, and December 31, 2007. SaTScan software (Information Management Services, Inc., Silver Spring, Maryland) was used to identify geographic clusters of significantly elevated syphilis rates over space and time. The authors graphed epidemic curves for 1) core areas, 2) outbreak areas, 3) neither core nor outbreak areas, and 4) noncore areas, where noncore areas included outbreaks, and stratified these curves according to demographic characteristics. Five clusters of significantly elevated primary and secondary syphilis rates were identified. A 5-year threshold was useful for differentiating core clusters from outbreak clusters. Epidemic curves for core areas, outbreak areas, neither core nor outbreak areas, and noncore areas were perfectly synchronized in phase trends and wavelength over time, even when broken down by demographic characteristics. Between epidemics, the occurrence of syphilis affected all demographic groups equally. During an epidemic, a temporary disparity in syphilis occurrence arose and a homogeneous core group of cases could be defined.

Treatment and care for injecting drug users with HIV infection: a review of barriers and ways forward

We review evidence for effectiveness, cost-effectiveness, and coverage of antiretroviral therapy (ART) for injecting drug users (IDUs) infected with HIV, with particular attention to low-income and middle-income countries. In these countries, nearly half (47%) of all IDUs infected with HIV are in five nations--China, Vietnam, Russia, Ukraine, and Malaysia. In all five countries, IDU access to ART is disproportionately low, and systemic and structural obstacles restrict treatment access. IDUs are 67% of cumulative HIV cases in these countries, but only 25% of those receiving ART. Integration of ART with opioid substitution and tuberculosis treatment, increased peer engagement in treatment delivery, and reform of harmful policies--including police use of drug-user registries, detention of drug users in centres offering no evidence-based treatment, and imprisonment for possession of drugs for personal use--are needed to improve ART coverage of IDUs.

Estimation of the number of injection drug users in St. Petersburg, Russia

The conjoined epidemics of HIV and injection drug abuse have progressed rapidly in many parts of the Russian Federation, including the City of St. Petersburg, which now has more cases of HIV than any other region in the country. Official estimates of the number of injection drug users (IDUs), which rely on official registration of IDUs, greatly underestimate their number. We have combined official statistics that register HIV cases and attribute risk to causes including injection drug use with data from a study that collected data from IDUs about their HIV serostatus and their history of HIV testing to estimate the number of IDUs in the city. We conclude that there are 83,118+/-5799 total IDUs. Since many IDUs have not been tested and even some who have been officially tested do not know their serostatus, a first step in countering the growing HIV epidemic among IDUs in St. Petersburg must be expanded access to HIV testing, prevention, and treatment that is targeted to IDUs.

Injecting equipment sharing in Russian drug injecting dyads

In this study, we investigated how individual attributes, dyad characteristics and social network characteristics may influence engaging in receptive syringe sharing, distributive syringe sharing and sharing cookers in injecting partnerships of IDUs in St Petersburg, Russia. We found that all three levels were associated with injecting equipment sharing, and that dyad characteristics were modified by characteristics of the social network. Self-reported HIV discordance and male gender concordance played a role in the risk of equipment sharing. Dyad interventions may not be sufficient to reduce injecting risk in IDU partnerships, but a combination of dyad and network interventions that target both IDU partnerships and the entire IDU population may be more appropriate to address injecting risk among IDUs.

Drug choice, spatial distribution, HIV risk, and HIV prevalence among injection drug users in St. Petersburg, Russia

Background

The HIV epidemic in Russia has been driven by the unsafe injection of drugs, predominantly heroin and the ephedrine derived psychostimulants. Understanding differences in HIV risk behaviors among injectors associated with different substances has important implications for prevention programs.

Methods

We examined behaviors associated with HIV risk among 900 IDUs who inject heroin, psychostimulants, or multiple substances in 2002. Study participants completed screening questionnaires that provided data on sociodemographics, drug use, place of residence and injection- and sex-related HIV risk behaviors. HIV testing was performed and prevalence was modeled using general estimating equation (GEE) analysis. Individuals were clustered by neighborhood and disaggregated into three drug use categories: Heroin Only Users, Stimulant Only Users, and Mixed Drug Users.

Results

Among Heroin Only Users, younger age, front/backloading of syringes, sharing cotton and cookers were all significant predictors of HIV infection. In contrast, sharing needles and rinse water were significant among the Stimulant Only Users. The Mixed Drug Use group was similar to the Heroin Only Users with age, front/back loading, and sharing cotton significantly associated with HIV infection. These differences became apparent only when neighborhood of residence was included in models run using GEE.

Conclusion

The type of drug injected was associated with distinct behavioral risks. Risks specific to Stimulant Only Users appeared related to direct syringe sharing. The risks specific to the other two groups are common to the process of sharing drugs in preparation to injecting. Across the board, IDUs could profit from prevention education that emphasizes both access to clean syringes and preparing and apportioning drug with these clean syringes. However, attention to neighborhood differences might improve the intervention impact for injectors who favor different drugs.

Vaccines for cocaine abuse

Treatments for cocaine abuse have been disappointingly ineffective, especially in comparison with those for some other abused substances. A new approach, using vaccination to elicit specific antibodies to block the access of cocaine to the brain, has shown considerable promise in animal models, and more recently in human trials. The mechanism of action for the antibody effect on cocaine is very likely to be the straightforward and intuitive result of the binding of the drug in circulation by antibodies, thereby reducing its entry into the central nervous system and thus its pharmacological effects. The effectiveness of such antibodies on drug pharmacodynamics is a function of both the quantitative and the qualitative properties of the antibodies, and this combination will determine the success of the clinical applications of anti-cocaine vaccines in helping addicts discontinue cocaine abuse. This review will discuss these issues and present the current developmental status of cocaine conjugate vaccines.

Substance abuse vaccines

Conventional substance-abuse treatments have only had limited success for drugs such as cocaine, nicotine, methamphetamine, and phencyclidine. New approaches, including vaccination to block the effects of these drugs on the brain, are in advanced stages of development. Although several potential mechanisms for the effects of antidrug vaccines have been suggested, the most straightforward and intuitive mechanism involves binding of the drug by antibodies in the bloodstream, thereby blocking entry and/or reducing the rate of entry of the drug into the central nervous system. The benefits of such antibodies on drug pharmacodynamics will be influenced by both the quantitative and the qualitative properties of the antibodies. The sum of these effects will determine the success of the clinical applications of antidrug vaccines in addiction medicine. This review will discuss these issues and present the current status of vaccine development for nicotine, cocaine, methamphetamine, phencyclidine, and morphine.