The Relationship Between Polysubstance Injection Drug Use, HIV Risk Behaviors, and Interest in Pre-Exposure Prophylaxis (PrEP) Among People Who Inject Drugs in Rural West Virginia.

OBJECTIVE: The opioid crisis has increased risks for injection drug use (IDU)-associated HIV outbreaks throughout the United States. Polysubstance use and syringe sharing are common among rural people who inject drugs (PWID). However, little is known about how polysubstance IDU affects engagement in HIV prevention efforts among non-urban PWID. This study assesses the associations between profiles of polysubstance injection, injection-related HIV risk, acquiring syringes from a syringe services program (SSP), HIV testing, and pre-exposure prophylaxis (PrEP) awareness and interest among PWID in rural Appalachia. METHOD: We used survey data from 392 respondents in Cabell County, West Virginia who had injected drugs in the past 6 months. We conducted a latent class analysis using seven measures of IDU and tested for associations with injection-related HIV risk, receiving syringes from an SSP, having been tested for HIV, and PrEP awareness and interest. RESULTS: We identified three classes of polysubstance IDU in our sample: polysubstance use, heroin and crystal methamphetamine use, and crystal methamphetamine and buprenorphine/suboxone use. The polysubstance use class had the highest injection-related HIV risk (81.8% at risk), high syringe acquisition at an SSP (67.7%), and highest rate of HIV testing (60.0%). PrEP awareness was low across the sample (30.0%), but most PWID expressed interest in using PrEP (57.7%). CONCLUSIONS: Patterns of polysubstance IDU have unique relationships with key HIV risk factors and protective behaviors. The expansion of harm reduction services in rural settings is warranted to prevent incident HIV infections.

Opioid withdrawal symptoms, frequency, and pain characteristics as correlates of health risk among people who inject drugs.

OBJECTIVE: Opioid withdrawal symptoms are widely understood to contribute to health risk but have rarely been measured in community samples of opioid using people who inject drugs (PWID). METHODS: Using targeted sampling methods, 814 PWID who reported regular opioid use (at least 12 uses in the last 30 days) were recruited and interviewed about demographics, drug use, health risk, and withdrawal symptoms, frequency, and pain. Multivariable regression models were developed to examine factors associated with any opioid withdrawal, withdrawal frequency, pain severity, and two important health risks (receptive syringe sharing and non-fatal overdose). RESULTS: Opioid withdrawal symptoms were reported by 85 % of participants in the last 6 months, with 29 % reporting at least monthly withdrawal symptoms and 35 % reporting at least weekly withdrawal symptoms. Very or extremely painful symptoms were reported by 57 %. In separate models, we found any opioid withdrawal (adjusted odds ratio [AOR] = 2.75, 95 % confidence interval [CI] = 1.52, 5.00) and weekly or more opioid withdrawal frequency (AOR = 1.94; 95 % CI = 1.26, 3.00) (as compared to less than monthly) to be independently associated with receptive syringe sharing while controlling for confounders. Any opioid withdrawal (AOR = 1.71; 95 % CI = 1.04, 2.81) was independently associated with nonfatal overdose while controlling for confounders. In a separate model, weekly or more withdrawal frequency (AOR = 1.69; 95 % CI = 1.12, 2.55) and extreme or very painful withdrawal symptoms (AOR = 1.53; 95 % CI = 1.08, 2.16) were associated with nonfatal overdose as well. CONCLUSIONS: Withdrawal symptoms among PWID increase health risk. Treatment of withdrawal symptoms is urgently needed and should include buprenorphine dispensing.

Outcome evaluation of a "common factors" approach to develop culturally tailored HIV prevention interventions for people who inject drugs.

BACKGROUND: Current models of HIV prevention intervention dissemination involve packaging interventions developed in one context and training providers to implement that specific intervention with fidelity. Providers rarely implement these programs with fidelity due to perceived incompatibility, resource constraints, and preference for locally-generated solutions. Moreover, such interventions may not reflect local drug markets and drug use practices that contribute to HIV risk. PURPOSE: This paper examines whether provider-developed interventions based on common factors of effective, evidence-based behavioral interventions led to reduction in drug-related HIV risk behaviors at four study sites in Ukraine. METHODS: We trained staff from eight nongovernmental organizations (NGOs) to develop HIV prevention interventions based on a common factors approach. We then selected four NGOs to participate in an outcome evaluation. Each NGO conducted its intervention for at least N = 130 participants, with baseline and 3-month follow-up assessments. RESULTS: At three sites, we observed reductions in the prevalence of both any risk in drug acquisition and any risk in drug injection. At the fourth site, prevalence of any risk in drug injection decreased substantially, but the prevalence of any risk in drug acquisition essentially stayed unchanged. CONCLUSIONS: The common factors approach has some evidence of efficacy in implementation, but further research is needed to assess its effectiveness in reducing HIV risk behaviors and transmission. Behavioral interventions to reduce HIV risk developed using the common factors approach could become an important part of the HIV response in low resource settings where capacity building remains a high priority.

Hepatitis C viral infection and imprisonment among Aboriginal and Torres Strait Islander and non-Indigenous people who inject drugs.

INTRODUCTION AND AIMS: An understanding of the relationship between hepatitis C viral (HCV) infection and contextual factors such as imprisonment may contribute to the development of targeted treatment and prevention programs. We examine the associations of imprisonment and drug dependence with lifetime exposure to HCV, and whether these associations differ for Aboriginal and Torres Strait Islander and non-Indigenous people who inject drugs. DESIGN AND METHODS: Respondent-driven sampling was used in major cities and 'peer recruitment' in regional towns of Queensland to obtain a community sample of people who injected drugs, which comprised 243 Indigenous and 227 non-Indigenous participants who had ever been tested for HCV. Data are cross-sectional. Two binary Poisson models were developed to examine associations for variables relating to imprisonment, Indigeneity and drug use history. RESULTS: Sharing needles and syringes in prison (adjusted risk ratio 1.25, 95% confidence interval 1.02-1.53) remained significantly associated with HCV infection after adjustment for Indigeneity, injecting drug use history and drug dependence. Opioid dependence and concurrent dependence on opioids and methamphetamine was also independently associated with HCV infection. DISCUSSION AND CONCLUSIONS: Sharing needles and syringes in prison is linked with HCV infection, for both Aboriginal and Torres Strait Islander and non-Indigenous people who inject drugs. Further development of treatment and prevention programs in prisons is required, with consideration of the role of opioid and methamphetamine dependence in HCV exposure.

HIV among people who inject drugs in Hungary.

BACKGROUND: Before 2014 (the year of closure of the two largest needle exchange programs in Hungary, which halved the number of available syringes in the country despite increased injecting risk practices) no HIV was reportedly acquired in Hungary among people who inject drugs (PWIDs) who were not also men who had sex with other men (MSM). In 2014, one and in 2015 two non-MSM PWIDs were newly diagnosed with HIV who supposedly became infected in Hungary, and both incident HIV cases in 2015 were diagnosed in the AIDS stage. In addition, two new (albeit supposedly imported) non-MSM PWID cases were also registered in the first three quarters of 2016, one of which subsequently was diagnosed with and then died of AIDS. At the same time, the prevalence of HCV doubled among PWIDs (from 24% to 49% in Hungary and from 34% to 61% in Budapest). CASE PRESENTATION: The case that we discuss in this paper is a male PWID, who was diagnosed with HIV and AIDS in May of 2015 and then died of AIDS the next month. His HIV infection status was detected with delay, and then appeared in the official statistics as an incident PWID HIV case and an incident PWID AIDS case, but not as an incident PWID AIDS death. No contact tracing followed, even though it would have been relatively easy considering the circumstances. To our knowledge, no HIV post-exposure protocol exists in hospitals, in case of HIV exposure due to an eventual needle-stick injury. CONCLUSIONS: Our paper draws attention to recently published HIV and AIDS surveillance data, and shows the failure of the system. While sounding the alarm based on three newly detected PWID HIV cases in the past 2 years may be premature, there are definitely serious problems in the HIV detection and tracing system among PWIDs in Hungary.

Trends in HIV and HCV Risk Behaviors and Prevalent Infection Among People Who Inject Drugs in New York City, 2005-2012.

BACKGROUND: We assess trends in HIV and hepatitis C virus (HCV) risk behaviors and prevalent infection among people who inject drugs (PWID) in New York City (NYC). METHODS: PWID in NYC were sampled using respondent-driven sampling in 2005, 2009, and 2012 (serial cross sections) for the Centers for Disease Control and Prevention-sponsored National HIV Behavioral Surveillance study. Participants were interviewed about their current (≤12 months) risk behaviors and tested for HIV and HCV. The crude and adjusted risk ratio (RR) and 95% confidence interval (95% CI) for linear time trends were estimated using generalized estimating equations regression with a modified Poisson model. RESULTS: The sample comprised 500, 514, and 525 participants in 2005, 2009, and 2012, respectively. Significant (P < 0.05) linear trends in risk behaviors included a decline in unsafe syringe sources (60.8%, 31.3%, 46.7%; RR = 0.86, 95% CI: 0.81 to 0.92), an increase in all syringes from syringe exchanges or pharmacies (35.4%, 67.5%, 50.3%; RR = 1.15, 95% CI: 1.09 to 1.22), and an increase in condomless vaginal or anal sex (53.6%, 71.2%, 70.3%; RR = 1.14, 95% CI: 1.09 to 1.19). Receptive syringe sharing (21.4%, 27.0%, 25.1%), sharing drug preparation equipment (45.4%, 43.4%, 46.7%), and having ≥2 sex partners (51.2%, 44.0%, 50.7%) were stable. Although HIV seroprevalence declined (18.1%, 12.5%, 12.2%), HCV seroprevalence was high (68.2%, 75.8%, 67.1%). In multivariate analysis, adjusting for sample characteristics significantly associated with time, linear time trends remained significant, and the decline in HIV seroprevalence gained significance (adjusted RR = 0.76, 95% CI: 0.64 to 0.91, P = 0.003). CONCLUSIONS: This trend analysis suggests declining HIV prevalence among NYC PWID. However, HCV seroprevalence was high and risk behaviors were considerable. Longitudinal surveillance of HIV and HCV risk behaviors and infections is needed to monitor trends and for ongoing data-informed prevention among PWID.

The effects of needle-sharing and opioid substitution therapy on incidence of hepatitis C virus infection and reinfection in people who inject drugs.

Although high hepatitis C virus (HCV) prevalence has been observed in people who inject drugs (PWID) for decades, research suggests incidence is falling. We examined whether PWIDs' use of opioid substitution therapy (OST) and their needle-and-syringe sharing behaviour explained HCV incidence. We assessed HCV incidence in 235 PWID in Melbourne, Australia, and performed discrete-time survival with needle-sharing and OST status as independent variables. HCV infection, reinfection and combined infection/reinfection incidences were 7·6 [95% confidence interval (CI) 4·8-11·9], 12·4 (95% CI 9·1-17·0) and 9·7 (95% CI 7·4-12·6) per 100 person-years, respectively. Needle-sharing was significantly associated with higher incidence of naive HCV infection [hazard ratio (HR) 4·9, 95% CI 1·3-17·7] but not reinfection (HR 1·85, 95% CI 0·79-4·32); however, a cross-model test suggested this difference was sample specific. Past month use of OST had non-significant protective effects against naive HCV infection and reinfection. Our data confirm previous evidence of greatly reduced HCV incidence in PWID, but not the significant protective effect of OST on HCV incidence detected in recent studies. Our findings reinforce the need for greater access to HCV testing and prevention services to accelerate the decline in incidence, and HCV treatment, management and support to limit reinfection.

Reduction in Needle Sharing Among Seattle-Area Injection Drug Users Across 4 Surveys, 1994-2013.

OBJECTIVES: We evaluated time trends in sharing needles and other injection equipment from 1994 to 2013 among injection drug users in the Seattle, Washington area. METHODS: We combined data from 4 sources: the Risk Activity Variables, Epidemiology, and Network (RAVEN) study, recruited from institutional settings; the Kiwi study, recruited from jails; National HIV Behavioral Surveillance system (NHBS) surveys, which used respondent-driven sampling; and surveys at needle-exchange sites. RESULTS: Levels of needle sharing were higher in the earlier studies: RAVEN, 1994 to 1997 (43%) and Kiwi, 1998 to 2002 (61%). In the NHBS surveys, the initial level of 44% in 2005 declined to 31% in the period 2009 to 2012. Across needle-exchange surveys (2009-2013) the level was 21%. There was a parallel reduction in sharing other injection equipment. These trends persisted after control for sociodemographic and risk-associated variables. There was a contemporaneous increase in the number of needles distributed by local needle exchanges and a decline in the number of reported HIV cases among injection drug users. CONCLUSIONS: The apparent long-term reduction in sharing injection equipment suggests substantial success in public health efforts to reduce the sharing of injection equipment.

Emerging Risks Due to New Injecting Patterns in Hungary During Austerity Times.

As a consequence of the massive restructuring of drug availability, heroin injection in Hungary was largely replaced by the injecting of new psychoactive substances (NPS) starting in 2010. In the following years in our sero-prevalence studies we documented higher levels of injecting paraphernalia sharing, daily injection-times, syringe reuse, and HCV prevalence among stimulant injectors, especially among NPS injectors. Despite the increasing demand, in 2012 the number of syringes distributed dropped by 35% due to austerity measures. Effects of drug market changes and the economic recession may have future epidemiological consequences. Study limitations are noted and future needed research is suggested.

Patterns of injection drug use cessation during an expansion of syringe exchange services in a Canadian setting.

BACKGROUND: Needle and syringe programmes (NSPs) have been shown to reduce HIV risk among people who inject drugs (IDUs). However, concerns remain that NSPs delay injecting cessation. METHODS: Individuals reporting injection drug use in the past six months in the greater Vancouver area were enrolled in the Vancouver Injection Drug Users Study (VIDUS). Annual estimates of the proportion of IDU reporting injecting cessation were generated. Generalized estimating equation (GEE) analysis was used to assess factors associated with injecting cessation during a period of NSP expansion. RESULTS: Between May 1996 and December 2010, the number of NSP sites in Vancouver increased from 1 to 29 (P<0.001). The estimated proportion of participants (n=2710) reporting cessation increased from 2.4% (95% confidence interval [CI]: 0.0-7.0%) in 1996 to 47.9% (95% CI: 46.8-48.9%) in 2010 (P<0.001). In a multivariate GEE analysis, the authors observed an association between increasing calendar year and increased likelihood of injecting cessation (Adjusted Odds Ratio=1.17, 95% CI: 1.15, 1.19, P<0.001). CONCLUSION: The proportion of IDU reporting injecting cessation increased during a period of NSP expansion, implying that increased NSP availability did not delay injection cessation. These results should help inform community decisions on whether to implement NSPs.

Needle and syringe distribution trends in Western Australia, 1990 to 2009.

INTRODUCTION AND AIMS: To describe needle and syringe distribution trends of needle and syringe programs (NSP) between 1990 and 2009 in Western Australia, and explore contributing factors within the national and state strategic and legislative environment. DESIGN AND METHODS: The number of needles and syringes distributed by each of the four NSP types [needle and syringe exchange program (NSEP); health service; pharmacy; vending machine] between 1990 and 2009 were stratified by time period and geographic location using Microsoft Excel. RESULTS: Total needle and syringe distribution over the 20-year period increased by eight-fold. Regional areas experienced the highest growth: 20-fold increase compared with seven-fold increase in metropolitan areas. The proportion of needles and syringes distributed through NSEPs increased from 33% to 62% between 1990 and 2009, and through health services increased from 3% to 8% between 1994 and 2009. The proportion distributed through pharmacies decreased from 67% to 28% between 1990 and 2009, and through vending machines from 7% to 1.3% between 1992 and 2009. National and state HIV and hepatitis C strategies guided NSP provision at an early stage, and expedited legislative amendments to allow for the operation of approved NSPs. DISCUSSION AND CONCLUSIONS: The majority of growth occurred through the NSEPs and health service NSPs, which are publicly funded NSPs and provide injecting equipment either on 'exchange' or free-of-charge respectively. The Health Department of Western Australia recognises the increasing reliance on publicly funded NSPs and the need to continue this cost-effective public health program.

A profile on HIV prevalence and risk behaviors among injecting drug users in Nigeria: should we be alarmed?

OBJECTIVE: Injecting drug use is now recognized as a significant risk factor for HIV in sub-Saharan Africa. We evaluated prevalence and correlates of HIV among injecting drug users (IDUs) in Nigeria. METHODS: A cross sectional design using respondent driven sampling was conducted in six states in 2010. Weighted HIV prevalence and injecting risk behaviors calculated using RDS analytic tool. Logistic regression was used to determine correlates of HIV infection, stratified by state. RESULTS: Total numbers of IDUs ranged from 197 in Lagos to 273 in Cross River and Oyo states. HIV prevalence was highest in Federal Capital Territory (FCT) at 9.3%, Kaduna 5.8%, Oyo 5.1%, Kano 4.9%, CR 3.3% and Lagos 3.0%. Although >90% of participants were male, females had higher HIV prevalence in all states surveyed except FCT (range: 7.4% in CR to 37.7% in Kano). Logistic regression showed that females were significantly more likely to be HIV positive in Kano [OR=33.2, 95% CI: 6.8-160.4], Oyo [AOR=15.9, 95% CI: 3.69-68.51], Lagos [OR=15.5, 95% CI: 2.41-99.5] and Kaduna states [AOR=19.6, 95% CI: 4.4-87.6]. For injecting risk behavior, only receptive sharing was associated with HIV [AOR=7.6, 95% CI: 1.2-48.7] and [AOR=0.2, 95% CI: 0.04-0.92] in Oyo and Kaduna states respectively. CONCLUSIONS: Considerable heterogeneity in the prevalence of HIV and associated risk behaviors exist among IDUs across Nigeria. Females had higher HIV prevalence among IDUs in five of six states, suggesting a need for targeted interventions for this hidden subgroup. Further research is needed to understand HIV transmission dynamics of IDUs in Nigeria. Community-based opioid substitution therapy and needle exchange programs should be implemented without delay.

Latent classes of heroin and cocaine users predict unique HIV/HCV risk factors.

BACKGROUND: Patterns of heroin and cocaine use vary and may be associated with unique risk factors for bloodborne infections. METHODS: Latent class analysis identified sub-populations of 552 heroin and cocaine users in Baltimore, Maryland. Using latent class regression, these classes were analyzed for associations with demographic characteristics, risky behaviors, Hepatitis C, and HIV. RESULTS: Three classes were found: Crack/Nasal-Heroin users (43.5%), Polysubstance users (34.8%), and Heroin Injectors (21.8%). Compared to Polysubstance users, Crack/Nasal-Heroin users were almost 7 times more likely to identify as Black (OR=6.97, 95% CI=4.35-11.2). Sharing needles was over 2.5 times more likely among Polysubstance users than among Heroin Injectors (OR=2.66, 95% CI=1.49-4.75). Crack/Nasal-Heroin users were 2.5 times more likely than Polysubstance users to exchange drugs for sex (OR=2.50, 95% CI=1.22-5.13). Crack/Nasal-Heroin users were less likely than Heroin Injectors to have Hepatitis C (OR=0.10, 95% CI=0.06-0.18), but no significant differences were found for HIV. CONCLUSIONS: Subpopulations of cocaine and heroin users differed in demographic classifications, HIV-risk behaviors, and Hepatitis C infection. All subpopulations included substantial numbers of HIV-positive individuals. Findings provide further evidence that non-injection drug users face significant infectious disease risk.

Individual-level syringe coverage among Needle and Syringe Program attendees in Australia.

BACKGROUND: Harm associated with injecting drug use is a significant public health issue and a major cause of morbidity and mortality, with global estimates of 3 million injectors infected with HIV and 8 million living with chronic hepatitis C virus (HCV) infection. Estimates of program coverage are widely used in the context of HIV prevention and are critical in determining the effectiveness of interventions such as Needle and Syringe Programs (NSPs). METHODS: Data from a national cross-sectional study of NSP attendees in Australia were used to estimate individual-level syringe coverage as a proportion of monthly injections covered by a new syringe. Univariate and multivariate logistic regressions modelled associations between demographics, injecting risk, anti-HIV and HCV prevalence and syringe coverage. The median number of syringes retained per NSP attendee per annum was also estimated. RESULTS: Twenty percent of participants had insufficient new syringes for all injections. Syringe reuse (including reuse of one's own syringe) was independently associated with syringe coverage of <100%. Conversely, procurement of syringes from an NSP was independently associated with syringe coverage ≥100%, with a greater protective effect occurring when NSP utilisation was combined with current engagement in opiate substitution therapy. The median number of syringes retained per participant per annum was 720, equivalent to 2 per day. CONCLUSIONS: While Australian NSP attendees report high syringe coverage by international standards, prevention efforts could be scaled up. Syringe reuse was associated with syringe coverage of <100%, suggesting the utility of reuse as a proxy for individual-level syringe coverage.

Evolución de la necesidad y cobertura de los programas de intercambio de jeringuillas en las prisiones españolas, 1992-2009. Una estimación corregida / Evolution of the need and coverage of syringe exchange programs in Spanish prisons, 1992-2009. A revised estimation

Introducción: El objetivo del presente artículo es subsanar el sesgo incluido en nuestro anterior original presentando una estimación corregida de la necesidad y cobertura de jeringuillas en las prisiones españolas en el período 1992-2009 Material y métodos: La provisión de jeringuillas procede de publicaciones oficiales. La necesidad se estimó aplicando métodos multiplicativos a datos secundarios de varias fuentes. La cobertura se estimó mediante el cociente entre provisión y necesidad, y la diferencia entre dichas magnitudes. Se corrigió el sesgo de estimación de necesidad detectado en el estudio original. Resultados: Los programas de intercambio de jeringuillas en prisión comenzaron en 1997. Su máxima cobertura se alcanzó en 2005, con un 36%, valor muy superior al estimado inicialmente, aunque disminuyó a la mitad en los cuatro años siguientes, con un 17.4% en 2009. Conclusiones: Debe valorarse la notable cobertura que se alcanzó con estos programas en España, pero su evolución más reciente nos lleva a enfatizar la necesidad de ser imaginativos para que las nuevas condiciones epidemiológicas y económicas no lleven a la desaparición de los mismos(AU)

Introduction: The objective of this paper is to amend the bias included in our previous work, presenting a corrected estimation of the need and coverage of syringes/needles in Spanish prisons between 1992 and 2009. Methods: Data on the provision of the needles exchange programs (NEPs) in prison is taken from official publications. The need was calculated by applying multiplicative methods to secondary data from several sources. Coverage was estimated as the quotient between provision and need and the difference between these magnitudes. The detected need estimate bias has been corrected. Results: NEP’s in prisons started in 1997. Their maximum coverage reached 36% in 2005, which is much higher than the initially estimated value. However, it decreased by half in the next four years, reaching 17.4% in 2009. Conclusion: The remarkable coverage reached by these programmes must be valued, but more recent evolution leads us to emphasize the need to be imaginative so that new epidemiological and economic circumstances do not lead to their disappearance(AU)

Evolución de la necesidad y cobertura de los programas de tratamiento con sustitutivos opioides e intercambio de jeringas en las prisiones españolas, 1992-2009 / Evolution of the need and coverage of opioid substitution treatments and needle exchange programmes in Spanish prisons, 1992-2009

Introducción: España es de los pocos países que ha implementado generalizadamente tratamientos con sustitutivos opioides (TSO) y programas de intercambio de jeringas (PIJ) para los consumidores de drogas en prisión. Se analiza la evolución de la necesidad, cobertura y oportunidad temporal de estas intervenciones en España durante 1992-2009. Material y métodos: La provisión de intervenciones procede de publicaciones oficiales. La necesidad se estimó aplicando métodos multiplicativos a datos secundarios de varias fuentes. La cobertura se estimó mediante el cociente entre provisión y necesidad, y la diferencia entre dichas magnitudes. La oportunidad temporal se estimó observando el decalaje entre el acmé de incidencia de consumo, de infección por VIH o de necesidad y las curvas de provisión. Resultados: Los TSO comenzaron en 1992. Su máxima cobertura se alcanzó en 2002 (63.8%), y posteriormente se estabilizó. Los PIJ comenzaron en 1997. Su máxima cobertura se alcanzó en 2006 (20.7%), pero disminuyó a la mitad en dos años. El retraso entre el acmé de las epidemias o de la necesidad y la máxima cobertura de las intervenciones fue de 8-25 años. Conclusiones: La implementación de TSO y PIJ en las prisiones españolas supuso un enorme avance de salud pública, pero el retraso en su implementación y la baja cobertura de los PIJ pueden haber limitado mucho su impacto potencial en la mejora de la salud de los consumidores de drogas en prisión. El descenso de la cobertura de los PIJ a la mitad en los últimos años es especialmente preocupante para la evolución de las epidemias de VIH y hepatitis C(AU)

Introduction: Spain is one of the few countries to have widely implemented opioid substitution treatments (OST) and needle exchange programmes (NEP) for drug users in prison. We analyze the evolution of the need, coverage and the timeliness of these interventions in Spain between 1992 and 2009. Methods: Data on the provision of interventions is taken from official publications. The need was calculated by applying multiplicative methods to secondary data from several sources. Coverage was estimated as the quotient between provision and need. Temporal opportunity was estimated by observing the gap between the acme of the incidence of consumption, of HIV infection or need and the curve of provision. Results: OST’s began to be implemented in 1992. In 2002 they reached their maximum coverage (63.8%) and subsequently stabilized. NEP’s started in 1997. Their maximum coverage reached 20.7% in 2006, but halved in a period of two years. The delay between the epidemic acme and the need and maximum intervention coverage was of 8-25 years. Conclusions: OST and NEP introduction in Spanish prisons was a great advance, but the delay in their implementation and the low level of NEP coverage could have limited their potential impact on the improvement of the health of incarcerated drug users. The decline of NEP coverage in recent years is a cause of major concern for the evolution of HIV and Hepatitis C epidemics(AU)

Modelling the impact on Hepatitis C transmission of reducing syringe sharing: London case study.

BACKGROUND: Hepatitis C virus (HCV) prevalence and incidence among injecting drug users (IDUs) has increased in London and rest of UK. To inform public health action, mathematical modelling is used to explore the possible impact of strategies to decrease syringe sharing. METHODS: A mathematical model was developed to simulate HCV transmission amongst IDUs in London. Because of parameter uncertainty, numerical search algorithms were used to obtain different model fits to HCV seroprevalence data from London for 2002-03. These simulations were used to explore the likely impact of HCV prevention activities that reduce syringe sharing amongst all IDUs, IDUs that have injected for greater than one year, or IDUs with lower or higher frequencies of syringe sharing. RESULTS: Key differences between model fits centred on how they simulated the high HCV incidence amongst new injectors, either through assuming increased HCV infectivity during acute infection, a large sub-group of high frequency syringe sharers, or increased sharing among new IDUs. Despite parameter uncertainty, the model projections suggest that modest reductions in syringe sharing frequency (<25%) will reduce the HCV seroprevalence in newly initiated IDUs (injecting less than four years) but much larger and sustained reductions (>50%) are required to reduce the HCV seroprevalence in long-term IDUs (injecting more than 8 years). Critically the model also suggested that large reductions in HCV seroprevalence will be achieved only if interventions target all IDUs and reach IDUs within 12 months of injecting. DISCUSSION: Public health interventions must reduce syringe sharing amongst all IDUs, including newly initiated IDUs, and be sustained for many years to reduce HCV infection. More accurate data on key behavioural (sharing frequency) and biological (percentage of infected IDUs that clear infection) parameters is required to improve model projections.

Trends in injection drug use behaviors over 10 years among street youth.

OBJECTIVES: To determine the temporal trends of initiation into injection drug use, current injection, and recent receptive sharing of injection paraphernalia among street youth. DESIGN: Data from two cohort studies conducted between 1995 and 2005 were combined. METHODS: Recruitment was done on an ongoing basis. Interviews were performed semi-annually. Overall and annual drug injection incidence rates were calculated with the person-time method. Poisson regression was used to assess the predictive power of calendar year on incidence rate. Generalized estimating equations (GEE) were used to assess linear trends in current injection among street youth and in recent receptive sharing of syringe and other injection paraphernalia among current injection drug users. RESULTS: By 31 March 2005, 1633 subjects had completed 8875 questionnaires. Most subjects were born in Canada (94%), their mean age at entry was 20 years, 68% were boys and almost half (44%) had injected drugs before recruitment. Among 778 never injectors at entry, 130 subjects initiated injection in 1898 person-years of follow-up (incidence rate: 6.8 per 100 person-years). When controlling for age, calendar year was not a significant predictor of incidence rate. Prevalence of current injection was stable (around 30%). Odds of both sharing behaviors decreased by approximately 10% per year. CONCLUSIONS: In addition to injection paraphernalia sharing reduction efforts, interventions aimed at preventing initiation into injection drug use among high-risk youth are needed.