The role of "long-term" and "new" injectors in a declining HIV/AIDS epidemic in Rio de Janeiro, Brazil

Recent increases in crack injection and associated risk factors among people who inject psychoactive drugs in England and Wales

BACKGROUND

Crack use is higher in the United Kingdom (UK) than other European countries. Crack is a stimulant with a short half-life, requiring frequent injection to maintain its euphoric effects, thus increasing the risk of blood borne viruses (BBVs) and skin and soft tissue infections (SSTIs). We assessed trends in the prevalence of current crack injection among people who inject drugs (PWID) and investigated harms and other factors associated with its use.

METHODS

We used data from the annual Unlinked Anonymous Monitoring Survey of PWID, which recruits people who have ever injected psychoactive drugs through specialist services. Participants provide a biological sample and self-complete a questionnaire. We included participants from England and Wales who had injected in the past month. We examined trends in crack injection over time (2011-2021) and factors associated with crack injection using multivariable logistic regression (2019-2021).

RESULTS

The proportion of people self-reporting crack injection in the past month almost doubled between 2011-2020/21, from 34 % (416/1237) to 57 % (483/850). Crack injection was more frequently reported by males than females (adjusted odds ratio 1.46, 95 % confidence interval: 1.15-1.87) and injected alongside heroin (6.67, 4.06-10.97) more frequently than alone. Crack injection was independently associated with injecting equipment sharing (1.64, 1.30-2.07), groin injection (2.03, 1.60-2.56) in the past month, overdosing in the past year (1.90, 1.42-2.53), homelessness in the past year (1.42, 1.14-1.77) and ever having hepatitis C infection (1.64, 1.31-2.06).

CONCLUSION

Crack injection has increased significantly over the past decade in England and Wales. People injecting crack are more likely to engage in behaviours that increase the risk of BBV and SSTI acquisition, such as needle/syringe sharing, groin injection and polydrug use. Harm reduction and drug treatment services should adapt to support the needs of this growing population of people injecting stimulants.

Characteristics associated with HIV and hepatitis C seroprevalence among sexual and injecting partners of HIV positive persons who inject drugs in Nairobi and coastal Kenya

Background

Persons who inject drugs (PWID) have higher HIV and hepatitis C virus (HCV) seroprevalence than the general population in many parts of sub-Saharan Africa (SSA). The seroprevalences of HIV and HCV are also higher in coastal Kenya than in Nairobi. Understanding drivers of regional HIV and HCV variation among PWID in Kenya may inform population-specific prevention interventions.

Methods

Using a cross-sectional study, we defined HIV and HCV seroprevalence among persons identified as sexual or injecting partners of HIV positive PWID in two regions of Kenya and used logistic regression to identify demographic and behavioral characteristics associated with higher seroprevalence.

Results

Among 2386 partners, 469 (19.7%) tested HIV positive and 297(12.4%) tested HCV antibody positive. Partners on the Coast were more likely to live with HIV (seroprevalences: Coast = 23.8%, Nairobi = 17.1%; p < 0.001) and be HCV antibody positive (seroprevalences: Coast = 17.0%, Nairobi = 8.6%; p < 0.001). After adjusting for sex, age, and years injecting and accounting for clustering by site, the higher prevalence of both diseases in the Coast remained significant for HIV (OR 1.68, 95% CI 1.13–2.51) but not for HCV (OR 1.72, 95% CI 0.84–3.74). Compared to those recruited in Nairobi, partners on the Coast were older (Coast = 35 years, Nairobi = 31 years; p < 0.001), more likely to be male (Coast = 77.6%, Nairobi = 61.7%; p < 0.001), to have paid (Coast = 59.2%, Nairobi = 32.8%; p < 0.001) or received (Coast = 44.2%, Nairobi 35.4%; p < 0.001) money for sex, or to have had sex with someone they knew to be HIV positive (Coast 22.0%, Nairobi 10.8%; p < 0.001). Partners who had injected for five or more years had 1.48 times greater odds (95% CI 1.20–1.82) of living with HIV compared to partners who injected less than 5 years and more than twice the odds of HCV (95% CI 1.84–4.11).

Conclusion

HIV and HCV seroprevalence among sexual and injecting partners of PWID was, respectively, 5 times and > 12 times greater than is reported among the general population in Kenya (4% and < 1%, respectively). Providing resources and education will be crucial to reduce exposure and to maintain the lower needle and equipment sharing that we observed compared to other studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07036-8.

Comparing Injecting Risk Behaviors of Long-Term Injectors with New Injectors in Tehran, Iran

BACKGROUND

Global estimates suggest there are 15.6 million people who inject drugs (PWID) of whom 17.8% are living with HIV.Few studies have characterized newly-onset injectors with long-term injectors and its association with injecting risk behaviors.

OBJECTIVES

We examined the relationship between length of injection and risk behaviors among people who inject drugs (PWID) in Tehran, Iran.

METHODS

A cross-sectional study was conducted among PWID, from March to August 2016 in Tehran, Iran. PWID were recruited by convenience and snowball sampling from five Drop-in Centers (DIC) located in the south of Tehran. Our primary independent variable was length of injecting career, defined as the number of months since injecting initiation. Those defined as new injectors (were injecting for less than 18 months), and long-term injectors (as injecting drugs for more than 18 months). We reported the adjusted odds ratio (aOR) point estimate and 95% confidence interval (CI95%) as the effect measure. The level of significance used in multiple logistic regression model was 0.05. We used STATA v. 11 for all analyzes.

RESULTS

The analytical sample comprised of 500 participants (100% male). Mean (±SD) age of PWID with a length of injection history was 31.2 ± 7.2 years. Overall, 270 (54%) (CI95%: 49.6%, 58.4%) of participants were long-term injectors. The average age of drug use initiation among long-term injectors group was lower as compared to new injectors group (31.2 vs. 29.4, p < 0.001). The odds of distributive syringe sharing among new injectors were two times higher than long-term injectors (AOR = 2.1, 95% CI 1.4-4.7). The odds of receptive syringe sharing were lower among new injectors group (AOR = 0.7, CI95% 0.2-0.87), compared to long-term injectors. New injectors had higher odds of reusing their own syringes (OR = 2.8, 95% CI: 1.4-5.7; p = 0.01).

CONCLUSIONS

Improvements in harm reduction service provision can occur through taregted risk reduction education for new injectors focusing on reducing distributive syringe sharing among them.

Impact of length of injecting career on HIV incidence among people who inject drugs

We examined the relationship between duration of injecting career and HIV seroconversion among people who inject drugs (PWID) in Vancouver, Canada. Data were derived from HIV-negative PWID enrolled in a prospective cohort study. We employed Kaplan-Meier methods and Cox regression to investigate the effect of length of time since injection drug use initiation on time to HIV seroconversion. In multivariable Cox analysis, duration of injecting career was negatively associated with time to HIV seroconversion (adjusted hazard ratio=0.82; 95% confidence interval [CI]: 0.69-0.97). Our findings highlight the need for interventions that target individuals who participate in high-risk drug use behaviors.

High Prevalence and Incidence of HIV and HCV Among New Injecting Drug Users With a Large Proportion of Migrants--Is Prevention Failing?

OBJECTIVES

The aim of this study was to assess differences in the prevalence of HIV and HCV infection and associated risk factors between new (injecting for ≤5 years) and long-term injectors and to estimate HIV/HCV incidence among new injectors.

METHODS

Cross-sectional study among people who inject drugs (PWID) who attended harm reduction centers in Catalonia in 2010-11. Anonymous questionnaires and oral fluid samples were collected. Poisson regression models were applied to determine the association between HIV/HCV infection and risk factors.

RESULTS

Of the 761 participants, 21.4% were new injectors. New injectors were younger than long-term injectors (mean age = 31.6 vs. 37.8) and were more likely to be immigrants (59.0% vs. 33.4%). HIV and HCV prevalence was 20.6% and 59.4% among new injectors, and estimated HIV and HCV incidence 8.7 and 25.1 /100 person-years, respectively. Among new injectors, HIV infection was associated with homelessness (PR = 3.10) and reporting a previous sexually transmitted infection (PR = 1.79). Reporting front/backloading (PR = 1.33) and daily injection (PR = 1.35) were risk-factors for HCV infection. For long-term injectors, HIV risk factors were: having shared syringes (PR = 1.85), having injected cocaine (PR = 1.38), reporting front/backloading (PR = 1.30) and ever having been in prison (PR = 2.03).

CONCLUSION

A large proportion of PWID in Catalonia are new injectors, a subgroup with a high level of both sexual and parenteral exposure and a high incidence rate of HIV/ HCV infections. It is important to improve early diagnosis of these infections among this group, in particular among migrants. To identify and address risk factors for homelessness PWID should be a priority.

Assessing the HIV-1 Epidemic in Brazilian Drug Users: A Molecular Epidemiology Approach

Person who inject illicit substances have an important role in HIV-1 blood and sexual transmission and together with person who uses heavy non-injecting drugs may have less than optimal adherence to anti-retroviral treatment and eventually could transmit resistant HIV variants. Unfortunately, molecular biology data on such key population remain fragmentary in most low and middle-income countries. The aim of the present study was to assess HIV infection rates, evaluate HIV-1 genetic diversity, drug resistance, and to identify HIV transmission clusters in heavy drug users (DUs). For this purpose, DUs were recruited in the context of a Respondent-Driven Sampling (RDS) study in different Brazilian cities during 2009. Overall, 2,812 individuals were tested for HIV, and 168 (6%) of them were positive, of which 19 (11.3%) were classified as recent seroconverters, corresponding to an estimated incidence rate of 1.58%/year (95% CI 0.92–2.43%). Neighbor joining phylogenetic trees from env and pol regions and bootscan analyses were employed to subtype the virus from132 HIV-1-infected individuals. HIV-1 subtype B was prevalent in most of the cities under analysis, followed by BF recombinants (9%-35%). HIV-1 subtype C was the most prevalent in Curitiba (46%) and Itajaí (86%) and was also detected in Brasília (9%) and Campo Grande (20%). Pure HIV-1F infections were detected in Rio de Janeiro (9%), Recife (6%), Salvador (6%) and Brasília (9%). Clusters of HIV transmission were assessed by Maximum likelihood analyses and were cross-compared with the RDS network structure. Drug resistance mutations were verified in 12.2% of DUs. Our findings reinforce the importance of the permanent HIV-1 surveillance in distinct Brazilian cities due to viral resistance and increasing subtype heterogeneity all over Brazil, with relevant implications in terms of treatment monitoring, prophylaxis and vaccine development.

HIV and incarceration: prisons and detention

The high prevalence of HIV infection among prisoners and pre-trial detainees, combined with overcrowding and sub-standard living conditions sometimes amounting to inhuman or degrading treatment in violation of international law, make prisons and other detention centres a high risk environment for the transmission of HIV. Ultimately, this contributes to HIV epidemics in the communities to which prisoners return upon their release. We reviewed the evidence regarding HIV prevalence, risk behaviours and transmission in prisons. We also reviewed evidence of the effectiveness of interventions and approaches to reduce the risk behaviours and, consequently, HIV transmission in prisons. A large number of studies report high levels of risk behaviour in prisons, and HIV transmission has been documented. There is a large body of evidence from countries around the world of what prison systems can do to prevent HIV transmission. In particular, condom distribution programmes, accompanied by measures to prevent the occurrence of rape and other forms of non-consensual sex, needle and syringe programmes and opioid substitution therapies, have proven effective at reducing HIV risk behaviours in a wide range of prison environments without resulting in negative consequences for the health of prison staff or prisoners.The introduction of these programmes in prisons is therefore warranted as part of comprehensive programmes to address HIV in prisons, including HIV education, voluntary HIV testing and counselling, and provision of antiretroviral treatment for HIV-positive prisoners. In addition, however, action to reduce overcrowding and improve conditions in detention is urgently needed.

Prevalence and correlates of needle-sharing among new and long-term injection drug users in southwest China

Three community-based surveys recruited 4,310 injection drug users (IDUs) in China from 2004 to 2006. Of the participants, 54.4% were ≤ 3-year new IDUs; 63.9% reported injecting more than two times daily; 31.5% shared needles in the last six months; 37.4% shared equipments in the last month; 30.2% reported their regular sex partners injected drugs; and 23.5% had commercial sex, with 52.2% reporting no condom use during last sex. The risky injection practices (sharing needles/equipments and high injection frequency) were less frequent among new IDUs, emphasizing that effective prevention needs to identify and intervene with IDUs early on. The study's limitations are noted.

HIV and risk environment for injecting drug users: the past, present, and future

We systematically reviewed reports about determinants of HIV infection in injecting drug users from 2000 to 2009, classifying findings by type of environmental influence. We then modelled changes in risk environments in regions with severe HIV epidemics associated with injecting drug use. Of 94 studies identified, 25 intentionally examined risk environments. Modelling of HIV epidemics showed substantial heterogeneity in the number of HIV infections that are attributed to injecting drug use and unprotected sex. We estimate that, during 2010-15, HIV prevalence could be reduced by 41% in Odessa (Ukraine), 43% in Karachi (Pakistan), and 30% in Nairobi (Kenya) through a 60% reduction of the unmet need of programmes for opioid substitution, needle exchange, and antiretroviral therapy. Mitigation of patient transition to injecting drugs from non-injecting forms could avert a 98% increase in HIV infections in Karachi; whereas elimination of laws prohibiting opioid substitution with concomitant scale-up could prevent 14% of HIV infections in Nairobi. Optimisation of effectiveness and coverage of interventions is crucial for regions with rapidly growing epidemics. Delineation of environmental risk factors provides a crucial insight into HIV prevention. Evidence-informed, rights-based, combination interventions protecting IDUs' access to HIV prevention and treatment could substantially curtail HIV epidemics.

HIV prevalence among female sex workers, drug users and men who have sex with men in Brazil: a systematic review and meta-analysis

Background

The Brazilian response towards AIDS epidemic is well known, but the absence of a systematic review of vulnerable populations ─ men who have sex with men (MSM), female sex workers (FSW), and drug users (DU) remains a main gap in the available literature. Our goal was to conduct a systematic review and meta-analysis of studies assessing HIV prevalence among MSM, FSW and DU, calculating a combined pooled prevalence and summarizing factors associated the pooled prevalence for each group.

Methods

Nine electronic databases (MEDLINE via PubMed, EMBASE, Cochrane CENTRAL, AIDSLINE, AMED, CINAHL, TOXNET, SciELO, and ISI-Web of Science) were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1999 to 2009. To be included in the review, studies had to measure HIV prevalence and/or incidence as the primary outcome among at least one specific population under analysis.

Results

The studies targeting the three populations analyzed mostly young participants aged 30 years or less. Among FSW, eight studies were selected (3,625 participants), consistently identifying higher condom use with sexual clients than with occasional and stable partners. The combined HIV prevalence for FSW was 6.2 (95% CI: 4.4-8.3). Ten studies targeting MSM were identified (6,475 participants). Unprotected anal intercourse was commonly reported on those studies, but with great variability according to the nature of the relationship - stable vs. occasional sex partners - and sexual practice - receptive vs. insertive anal sex. Pooled HIV prevalence for MSM was 13.6 (95% CI: 8.2-20.2). Twenty nine studies targeting DU were identified (13,063 participants). Those studies consistently identified injection drug use and syringe/needle sharing as key predictors of HIV-infection, as well as engagement in sex work and male-to-male sex. The combined HIV prevalence across studies targeting DU was 23.1 (95% CI: 16.7-30.2).

Conclusions

FSW, MSM and DU from Brazil have a much risk of acquiring HIV infection compared to the general population, among which HIV prevalence has been relatively low (~0.6%). Those vulnerable populations should be targeted by focused prevention strategies that provide accurate information, counseling and testing, as well as concrete means to foster behavior change (e.g. access to condoms, drug abuse treatment, and clean syringes in the case of active injecting drug users), tailored to gender and culture-specific needs. Programs that provide these services need to be implemented on public health services throughout the country, in order to decrease the vulnerability of those populations to HIV infection.

Binge use and sex and drug use behaviors among HIV(-), heterosexual methamphetamine users in San Diego

This study identified sociodemographic factors, drug using practices, sexual behaviors, and motivational factors associated with binge (a period of uninterrupted) methamphetamine (MA) use among heterosexual MA users.

SAMPLE AND METHOD

The FASTLANE study provided cross-sectional data collected by audio computer-assisted self-interview (ACASI) between June 2001 and August 2004 from 451 HIV-negative MA users in San Diego, California, USA who had engaged in unprotected sex and used MA in the previous two months.

RESULTS

The study sample was 67.8% male, 49.4% Caucasian, 26.8% African-American, and 12.8% Hispanic with a mean age of 36.6 years; 183 (40.5%) reported binge use in the past 2 months. Compared with non-binge users, binge users of MA were more likely to report risky drug use and sex behaviors and differed in motivations to initiate and currently use MA. The final logistic regression model for binge use included more days of MA use in the last month, ever treated for MA use, injection drug use, higher Beck Depression Inventory score, "experimentation" as a motivation for initiating MA use, and engaging in sex marathons while high on MA. HIV prevention efforts should differentiate and address these differences in motivations for MA use and the associated HIV-risk sex and drug use behaviors as key targets for effective intervention.

Distribution of CCR5 genotypes and HLA Class I B alleles in HIV-1 infected and uninfected injecting drug users from Rio de Janeiro, Brazil

Host genetic factors play an important role in the HIV epidemic dynamics, and have been considered in studies assessing susceptibility/resistance to HIV-1 infection as well as clinical evolution. Class I and Class II HLA alleles have been associated with the heterogeneity of HIV-1 infection susceptibility, as protective or risk factors for HIV-1 transmission. Moreover, a 32-base pair deletion in the HIV-1 CCR5 gene-coding region confers resistance to HIV-1 infection in homozygous individuals for the deleted allele. In this study, DNA samples from HIV-1 infected and uninfected injecting drug users (IDUs) from Rio de Janeiro were PCR amplified to determine CCR5 genotypes based on the presence of the CCR5Delta32 mutation and typed for the HLA-B locus, in an attempt to assess possible associations between these genetic factors and susceptibility/resistance to HIV-1 infection. The distribution of CCR5 genotypes between the two IDU groups did not differ. The homozygous mutant genotype Delta32/Delta32 was not found in this study. Except for HLA-B*45 (4.0% vs. 3.0%; p=0.04) and for B*51 (12.1% vs. 4.4%; p=0.002), no statistically significant differences were made evident when analyzing the frequencies of each HLA-B allele between Caucasian and non-Caucasian IDUs. The most frequent HLA-B alleles were B*15; B*35; B*44 and B*51. Although some differences in the allele frequencies could be observed between the two IDU groups, none of these was statistically significant. Therefore, no putative association between these genetic markers and susceptibility/resistance to HIV-1 infection could be made evident in the present study. So far, the assessment of genetic markers among the IDU population has been restricted to North American, European, and Asian studies and this report represents a pioneer descriptive study of the distribution of CCR5 genotypes and HLA-B alleles in Rio de Janeiro, Brazil.

Comparison of injecting drug users who obtain syringes from pharmacies and syringe exchange programs in Tallinn, Estonia

BACKGROUND

Both syringe exchange programs (SEPs) and pharmacy sales of syringes are available in Estonia, though the current high incidence and high prevalence of HIV among injection drug users (IDUs) in Tallinn, Estonia requires large-scale implementation of additional harm reduction programs as a matter of great urgency. The aims of this report were to compare risk behavior and HIV infection and to assess the prevention needs among IDUs who primarily use pharmacies as their source of sterile syringes with IDUs who primarily use SEPs in Tallinn.

METHODS

A cross-sectional study using respondent-driven sampling was used to recruit 350 IDUs for an interviewer-administered survey and HIV testing. IDUs were categorized into two groups based on their self-reported main source for syringes within the last six months. Odds ratios with 95% CI were used to compare characteristics and risk factors between the groups.

RESULTS

The main sources of sterile needles for injection drug users were SEP/SEP outreach (59%) and pharmacies (41%). There were no differences in age, age at injection drug use initiation, the main drug used or experiencing overdoses. Those IDUs using pharmacies as a main source of sterile needles had lower odds for being infected with either HIV (AOR 0.54 95% CI 0.33-0.87) or HCV (AOR 0.10 95% CI 0.02-0.50), had close to twice the odds of reporting more than one sexual partner within the previous 12 months (AOR 1.88 95% CI 1.17-3.04) and engaging in casual sexual relationships (AOR 2.09 95% CI 1.24-3.53) in the last six months.

CONCLUSION

The data suggest that the pharmacy users were at a less "advanced" stage of their injection career and had lower HIV prevalence than SEP users. This suggests that pharmacies could be utilized as a site for providing additional HIV prevention messages, services for IDUs and in linking IDUs with existing harm reduction services.

Interventions to reduce HIV transmission related to injecting drug use in prison

The high prevalence of HIV infection and drug dependence among prisoners, combined with the sharing of injecting drug equipment, make prisons a high-risk environment for the transmission of HIV. Ultimately, this contributes to HIV epidemics in the communities to which prisoners return on their release. We reviewed the effectiveness of interventions to reduce injecting drug use risk behaviours and, consequently, HIV transmission in prisons. Many studies reported high levels of injecting drug use in prisons, and HIV transmission has been documented. There is increasing evidence of what prison systems can do to prevent HIV transmission related to injecting drug use. In particular, needle and syringe programmes and opioid substitution therapies have proven effective at reducing HIV risk behaviours in a wide range of prison environments, without resulting in negative consequences for the health of prison staff or prisoners. The introduction of these programmes in countries with an existing or emergent epidemic of HIV infection among injecting drug users is therefore warranted, as part of comprehensive programmes to address HIV in prisons.

Epidemiological and genetic analyses of Hepatitis C virus transmission among young/short- and long-term injecting drug users from Rio de Janeiro, Brazil

BACKGROUND

Injecting drug users (IDU) have a key role in Hepatitis C Virus (HCV) epidemiology. Young/short-term IDUs constitute a target group for preventive/harm reduction interventions.

OBJECTIVES

To investigate HCV transmission among young/short-term (ST) and long-term (LT) IDUs, from the perspective of epidemiology and molecular biology.

STUDY DESIGN

Cross-sectional study assessing the prevalence of HCV infection/genotypes, as well as risk behaviours/practices among IDUs from Rio de Janeiro. Phylogenetic analyses were performed and the extent of segregation between sequences was quantified by the Association Index.

RESULTS

ST were more likely to engage into needle-sharing (p=.021) and LT to attend Needle Exchange Programs (p=.006). HCV prevalence was 10.1% vs. 23.4% among initiates and LT, respectively (p<.001). Older age vs. imprisonment and longer duration of IDU career were independent predictors for HCV infection among ST and LT, respectively. Among the latter, NEP attendance was inversely associated with viral infection. HCV3a infections were the most prevalent. A moderate extent of phylogenetic segregation between sequences was found, suggestive of transmission between IDU subgroups.

CONCLUSIONS

The lower HCV prevalence among young/short-term IDUs cannot be viewed with complacency, due to their frequent engagement into direct/indirect sharing practices and the ongoing transmission between IDU subsets. To avert new infections, preventive/harm reduction policies must be tailored to empirical findings.

Trends in HCV prevalence, risk factors and distribution of viral genotypes in injecting drug users: findings from two cross-sectional studies

In the last decade, a declining prevalence of HCV infection has been described in injecting drug users (IDUs) in different countries. This study is the first to assess temporal trends in drug-injecting patterns, HCV infection rates and viral genotype distribution in 770 Brazilian IDUs, recruited by two cross-sectional studies (1994-1997 and 1999-2001). A substantial decline in the prevalence of HCV infection was found over the years (75% in 1994 vs. 20.6% in 2001, P<0.001) that may be a consequence of the significant reduction in the overall frequencies of drug injection and needle-sharing, as well as the participation of IDUs in initiatives aimed at reducing drug-related harm. No trend was found in terms of viral genotype distribution. Despite the favourable scenario, preventive measures must be maintained, especially in vulnerable subgroups such as young or new injectors, where risky behaviours through direct and indirect sharing practices remain common.

High-prevalence and high-estimated incidence of HIV infection among new injecting drug users in Estonia: need for large scale prevention programs

OBJECTIVE

To examine HIV risk behavior and HIV infection among new injectors in Tallinn, Estonia. Design and methods Data from two cross-sectional surveys of injecting drug users (IDUs) recruited from a syringe exchange program (N = 162, Study 1) or using respondent driven sampling (N = 350, Study 2). Behavioral surveys were administered; serum samples were collected for HIV testing. Subjects were categorized into new injectors (injecting < or = 3 years) and long-term injectors (injecting > 3 years).

RESULTS

Twenty-eight of 161 (17%, Study 1) and 73/350 (21%, Study 2) of the study subjects were new injectors. HIV infection was substantial among the newer injectors: HIV prevalence was 50% (Study 1) and 34% (Study 2), and estimated HIV incidence 31/100 PY and 21/100 PY, respectively. In Study 2, new injectors were more likely to be female and ethnic Estonian and less likely to be injecting daily compared with long-term injectors. No significant difference was found among two groups on sharing injecting equipment or reported number of sexual partners.

CONCLUSIONS

A continuing HIV epidemic among new injectors is of critical public health concern. Interventions to prevent initiation into injecting drug use and scaling up HIV prevention programs for IDUs in Estonia are of utmost importance.

Trends in drug resistance mutations in antiretroviral-naïve intravenous drug users of Rio de Janeiro

DNA sequencing of a pol gene fragment from drug-naive injecting drug users samples obtained at two time points of the Brazilian AIDS epidemic (Pre-HAART era: 1994 to early 1997, n = 27; post-HAART era: 1999-2001, n = 38) was undertaken to assess HIV-1 antiretroviral drug resistance mutations and subtyping profiles. Genotypic analysis revealed the presence of PR primary L90M, D30N, M46I, and V82A mutations in 7.9% of the post-HAART group, and a high frequency of secondary mutations (84.2%). Nucleoside RT-associated mutations were observed in 13.2%. In the pre-HAART group, a higher frequency of RT mutations was observed (22.2%) and no PR primary mutations were found, in agreement with the introduction of protease inhibitors (PIs) in therapy during the same period. The identification of 7.9% of drug-naive injecting drug users already bearing RT/PR primary resistance mutations in the post-HAART era group constitutes a major concern in terms of dissemination of drug resistant viruses. The resistance mutations profile of the individuals may reflect the context of antiretroviral treatment in Brazil at the sample collection periods (1994-1997 and 1999-2001). In spite of the differences observed in the drug resistance profiles, similar frequencies of subtype B (63.0 vs. 73.7%), F (22.2 vs. 10.5%), and recombinant B/F (14.8 vs. 15.8%) viruses were found, respectively, in the pre- and post-HAART groups.

Profile of male Brazilian injecting drug users who have sex with men

This study aims to characterize the profile of male injecting drug users who have sex with other men (MSM IDUs) recruited through a cross-sectional multi-city survey (AjUDE-Brasil II Project) in six Brazilian cities, in 2000-2001. MSM IDUs were compared to other male IDUs using bivariate and multivariate procedures (logistic regression and answer tree analysis with the CHAID algorithm). Among the 709 male IDUs, 187 (26.4%) reported ever having had sex with other men, while only 37 reported sex with other men in the previous six months. MSM IDUs were more likely to be unemployed (OR = 2.3), to have injected tranquilizers (OR = 3.6), and to be HIV-seropositive (OR = 2.1), compared to other male IDUs. Male same-sex relations in this subgroup appear to be associated with strategies to finance drug consuming habits, including sex for drugs with occasional female partners or obtaining injection paraphernalia from occasional sex partners. Further studies should focus on this especially vulnerable subgroup of IDUs, due to the bidirectional and complex interrelationships between their drug injecting habits and sexual risk behaviors.

Syringe exchange programs in Brazil: preliminary assessment of 45 programs

The present study aims to evaluate the current operation of Brazilian syringe exchange programs (SEP). After consulting national and regional networks of people working in projects/programs aiming to reduce drug-related harm, we identified 134 potential participant programs. Unfortunately, only 45 SEPs answered a survey, even after repeated attempts. The survey addressed: coverage, funding, procurement of basic supplies, managerial capacity, and the local political environment. Findings were triangulated with in-depth interviews with key informants. The main findings included: satisfactory adherence to the initiatives and adequate documentation, but deficiencies in terms of coverage and monitoring, and uneven procurement of resources. Program personnel work mostly on a provisional basis, despite the efforts of local coordinators. Most programs are funded by the National STDs/AIDS Program. A comprehensive agenda aiming to improve current operations should include: concerted efforts to improve local and regional databanks, incentives/sanctions toward full accountability of initiatives carried by the programs, and a genuine culture of monitoring and evaluation.

HCV and HIV infection and co-infection: injecting drug use and sexual behavior, AjUDE-Brasil I Project

This study aimed to characterize sexual and drug-use behaviors in injecting drug users (IDUs) in relation to single hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infection and HCV/HIV co-infection. The sample consisted of 272 IDUs enrolled in the AjUDE-Brasil I Project, a cross-sectional multi-center study conducted in five Brazilian cities in 1998. Data were collected with a structured questionnaire using self-reported risk behavior, and HCV and HIV serological status used ELISA on filter paper. IDUs were clustered in four distinct groups: HCV/HIV seronegative; HCV mono-infected; HIV mono-infected; and HCV/HIV co-infected. Active sharing of injecting equipment was associated with HCV infection (p = 0.001). Sexual behavior variables, especially male same-sex sexual relations, were consistently associated with HIV infection. HCV/HIV co-infection was associated with both sexual and drug use variables. It was possible to distinguish different behavioral indicators for HCV and HIV infection and co-infection in this population.

Reconstructing the AIDS epidemic among injection drug users in Brazil

The HIV/AIDS epidemic among injection drug users (IDUs) in Brazil has been unique in terms of temporal and geographical contrasts. This analysis explores these contrasts through the use of multilevel modeling. Standardized AIDS incidence rates among IDUs for Brazilian municipalities (1986-2000) were used as the dependent variable, with a set of social indicators as independent variables (covariates). In some States of the North/Northeast, the epidemic among IDUs has been incipient. The São Paulo epidemic extended to reach a network of municipalities, most of which located far from the capital. More recently, on a smaller scale, a similar extension has been observed in the southernmost States of the country. Both "number of physicians per inhabitant" and "standard distance to the State capital" were found to be associated with AIDS incidence. AIDS cases among IDUs appeared to cluster in wealthier, more developed municipalities. The relative weight of such extensive dissemination in key, heavily populated States prevails in the Brazilian IDU epidemic, defining a central-western-southeastern strip of wealthier middle-sized municipalities and more recently a southern strip of municipalities deeply affected by the epidemic in this population.

A randomized trial of audio computer and in-person interview to assess HIV risk among drug and alcohol users in Rio De Janeiro, Brazil

This study compares drug patterns and prevalence of risk behaviors in a randomized trial using two methods of administration, Audio Computer-Assisted Self-Interview (ACASI) and Interviewer-Administered Questionnaire (IAQ), among drug users seeking treatment in a drug treatment center. We randomized 735 participants: 367 to ACASI and 368 to IAQ. No significant difference in sociodemographic variables were found between subjects in the two arms of the study. Those interviewed by ACASI were more likely to report use on 7 of 10 substances assessed. Rates of reporting of sexual risk behaviors (male-to-male and commercial sex) were higher among participants in the ACASI arm. ACASI seems to be a key resource in improving the reporting of sensitive data in Brazil, as it has been in prior international studies.

Injecting drug users who are (un)aware of their HIV serostatus: findings from the multi-center study AjUDE-Brasil II

This study aimed to characterize the profiles of injecting drug users (IDUs) who were unaware of their HIV serostatus, given the importance of this information for prevention strategies, especially in this vulnerable population, key to the HIV/AIDS dynamic. As part of a cross-sectional multi-city survey, IDUs were interviewed and HIV-tested by the ELISA technique. IDUs were categorized according to knowledge of their own HIV status as either aware or unaware. Means, averages, and proportions were compared between the groups using bi- and multivariate analyses. Of 857 IDUs interviewed, 34.2% were unaware of their HIV serostatus. Those who were unaware were more likely: to have been recruited at sites where the HIV prevalence rate was considered medium (> 10 to 50%; odds ratio = 8.0) or high (> 50%; 4.0); to be illiterate (OR = 4.54); to have no prior HIV test (OR = 2.22); to be male (OR = 1.81); and to have been enrolled more recently in syringe-exchange programs (OR = 1.69). HIV prevention programs should target both individuals at risk and HIV-positive individuals. Programs to expand access to HIV testing are pivotal and should be tailored to specific contexts and populations.

Is human immunodeficiency virus/acquired immunodeficiency syndrome decreasing among Brazilian injection drug users? Recent findings and how to interpret them

We briefly review findings from Brazilian settings where the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic among injection drug users (IDUs) seems to be decreasing, highlighting recent findings from Rio de Janeiro and discussing methodological alternatives. Former analyses using serologic testing algorithm for recent HIV seroconversion have shown that HIV incidence has been low in IDUs recruited by two different surveys carried out in Rio, where low injection frequencies and infection rates have been found among new injectors. The proportion of AIDS cases among IDUs in Rio has been fairly modest, compared to São Paulo and especially to the southernmost states. Notwithstanding, the interpretation of findings from serial surveys constitutes a challenge, magnified in the assessment of HIV spread among IDUs due to the dynamic nature of the drug scenes and limitations of sampling strategies targeting hard-to-reach populations. Assessment of epidemic trends may profit from the triangulation of data, but cannot avert biases associated with sampling errors. Efforts should be made to triangulate data from different sources, besides exploring specific studies from different perspectives. In an attempt to further assess the observed trends, we carried out original analyses using data from Brazilian AIDS databank.

HIV-1 infection among injection and ex-injection drug users from Rio de Janeiro, Brazil: prevalence, estimated incidence and genetic diversity

BACKGROUND AND OBJECTIVES

Due to their behavioral conditions and vulnerability, injection drug users (IDUs) are prone to multiple simultaneous or sequential infections with distinct HIV-1 subtypes and variants, making them a key population for molecular epidemiology surveillance. In the present study, we evaluated HIV-1 infection seroprevalence, genetic diversity and estimated incidence among IDUs and ex-injection drug users (ex-IDUs) from Rio de Janeiro, Brazil.

STUDY DESIGN

Six hundred and eight IDUs and ex-IDUs, recruited between 1999 and 2001, were interviewed and agreed to donate 30 ml of blood. The serologic status for HIV infection was determined by two ELISAs and confirmed by IFA. CD4+ T-cell percentages were assessed by flow cytometry. HIV-1 positive samples were submitted to viral load quantification. DNA samples were PCR amplified and HIV-1 subtypes were determined using env and gag HMA.

RESULTS AND CONCLUSIONS

Forty-eight (7.89%) individuals were seropositive for HIV-1 infection. The seroincidence of HIV-1 infection was estimated as 0.76%. HIV-1 env and gag subtyping identified 29 (69%) samples as belonging to subtype B, 7 (16.7%) to subtype F, and 6 (14.3%) discordant env/gag genomes infections, indicating the circulation of recombinant viruses in this population.