Drug use and risk of bloodborne infections: a survey of female prisoners in British Columbia

BACKGROUND: Clinicians working in a women's prison in British Columbia observed hepatitis C sero-conversion among inmates, prompting this study to determine: the characteristics of women who do and do not report illicit drug use in prison; patterns of drug use inside prison; factors associated with illicit drug use that might contribute to bloodborne transmission inside prison. METHODS: A cross-sectional observational data set was created using an anonymous 61-item self-administered survey. RESULTS: Eighty-three percent (104/126) of eligible inmates participated. Seventy-four percent (77/104) reported their current prison sentence was related to illicit drug use and 25% (26/104) reported their ethnicity as Aboriginal. Ninety-three percent (97/104) reported a prior history of illicit drug use, of whom 70% (68/97) reported a history of injection drug use. Thirty-six percent (37/104) reported illicit drug use in prison, and 21% (22/104) reported injection drug use in prison. Fifty-two percent (54/104) reported hepatitis C sero-positivity, and 8% (8/104) reported HIV sero-positivity. Of the 22 women who reported prison injection drug use, 91% (20/22) reported hepatitis C infection and 86% (19/22) reported injecting with shared needles inside prison, with or without bleach cleaning. Women were more likely to report illicit drug use in prison if they had had illegal sources of income prior to incarceration (p=0.0081, OR 3.19), had previously injected drugs (p=0.036, OR 2.97), and had first injected drugs at a friend's house (p=0.066, OR 2.70). INTERPRETATION: The majority of women reporting prison injection drug use also reported hepatitis C sero-positivity and shared needle use. Canadian prisons are risk situations for transmission of bloodborne pathogens, and provide opportunities for harm reduction strategies.     

The prevalence and the risk behaviours associated with the transmission of hepatitis C virus in Australian correctional facilities

This study measured the prevalence and the risk factors associated with HCV antibody-positive prisoners. A total of 630 prisoners completed a questionnaire about risk behaviours associated with HCV transmission and were tested for HCV antibody from a blood test. Of these 362 (57.5%) prisoners were HCV antibody positive. A total of 436 (68.8%) prisoners reported ever injecting drugs and 332 reported injecting drugs in prison. HCV-positive prisoners were more likely to have injected drugs (OR 29.9) and to have injected drugs in prison during their current incarceration (OR 3.0). Tattooing was an independent risk factor for being HCV positive (OR 2.7). This is the first study conducted on prisoners that has identified having a tattoo in prison as a risk factor for HCV. Injecting drugs whilst in prison during this incarceration was also a risk factor for HCV. Our results show prisoners who injected drugs outside of prison continue to inject in prison but in a less safe manner.     

Transmission of Hepatitis C Virus among Prisoners,Australia, 2005–2012

Hepatitis C virus (HCV) is predominantly transmitted between persons who inject drugs. For this population, global prevalence of HCV infection is high and incarceration is common and an independent risk factor for HCV acquisition. To explore HCV transmission dynamics in incarcerated populations, we integrated virus sequences with risk behavior and spatiotemporal data and analyzed transmission clusters among prisoners in Australia. We detected 3 clusters of recent HCV transmission consisting of 4 likely in-custody transmission events involving source/recipient pairs located in the same prison at the same time. Of these 4 events, 3 were associated with drug injecting and equipment sharing. Despite a large population of prisoners with chronic HCV, recent transmission events were identified in the prison setting. This ongoing HCV transmission among high-risk prisoners argues for expansion of prevention programs to reduce HCV transmission in prisons.     

Prevalence and Correlates of HCV,HVB, and HIV Infection among Prison Inmates and Staff,Hungary

The aim of this national, multicenter, cross-sectional study was to assess the prevalence of hepatitis B (HBV), hepatitis C (HCV), and human immunodeficiency viruses (HIV) among prisoners, and to identify related risk behaviors including injection drug use. Overall, 4,894 inmates from 20 prisons were enrolled. To have a comparison group, prison staff were also asked to take part. Altogether, 1,553 of the 4,894 inmates from seven prisons completed a questionnaire on risk behaviors. According to the survey, 1.5%, 4.9%, and 0.04% of the prisoners were tested positive for HBsAg, anti-HCV and anti-HIV, respectively. These prevalence data are among the lowest reported from prisons worldwide, although comparable to the Central European data. The prevalence of HBV, HCV, and HIV in the Hungarian prison staff was low (0.38%, 0.47%, and 0%, respectively). The rate of HCV infection was significantly higher among inmates who have ever injected drugs (22.5%) than among inmates who reported they had never injected drugs (1.1%). This first prevalence study of illegal drug injection-related viral infections among Hungarian prisoners points out that ever injecting drugs is the main reason for HCV infection among inmates. The opportunity to reach drug users infected with HCV for treatment underlines the importance of screening programs for blood-borne viruses in prisons.     

Prevalence of HIV, hepatitis B, and hepatitis C antibodies in prisoners in England and Wales: a national survey

Prisoners in eight of the 135 prisons in England and Wales were surveyed in 1997 and 1998 to study the prevalence of and risk factors for transmission of bloodborne viruses in prison. Subjects voluntarily completed a risk factor questionnaire and provided oral fluid specimens for unlinked anonymous testing for the presence of antibodies to HIV, hepatitis C virus (HCV), and the core antigen of hepatitis B virus (HBc). Almost 8% (4778) of the total of 60,561 prisoners were eligible and four fifths (3942) of those eligible took part. Among all those tested (3930) 0.4% (14) were positive for anti-HIV, 8% (308) for anti-HBc, and 7% (293) for anti-HCV (the anti-HBc and anti-HCV prevalences were not adjusted for assay sensitivities of 82% and 80%, respectively). Twenty-four per cent (777/3176) of adult prisoners reported ever having injected drugs, 30% of whom (224/747) reported having injected in prison. Three quarters of those who injected in prison (167/224) shared needles or syringes. Among adult injecting drug users, 0.5% (4/775) had anti-HIV, 31% (240/775) anti-HCV, and 20% (158/775) anti-HBc. The presence of anti-HCV and anti-HBc was associated with injecting inside prison and number of previous times in prison. The results suggest that hepatitis viruses are probably being transmitted in prisons through sharing non-sterile injecting equipment and that a risk of HIV transmission exists. Harm minimisation measures for the 6% of prisoners who continue to inject while in prison should be strengthened.     

Modelling alternative strategies for delivering hepatitis B vaccine in prisons: the impact on the vaccination coverage of the injecting drug user population

Since 2001 hepatitis B vaccination has been offered to prisoners on reception into prisons in England and Wales. However, short campaigns of vaccinating the entire population of individual prisons have achieved high vaccination coverage for limited periods, suggesting that short campaigns may be a preferable way of vaccinating prisoners. A model is used that describes the flow of prisoners through prisons stratified by injecting status to compare a range of vaccination scenarios that describe vaccination on prison reception or via regular short campaigns. Model results suggest that vaccinating on prison reception can capture a greater proportion of the injecting drug user (IDU) population than the comparable campaign scenarios (63% vs. 55.6% respectively). Vaccination on prison reception is also more efficient at capturing IDUs for vaccination than vaccination via a campaign, although vaccination via campaigns may have a role with some infections for overall control.     

Prevalence and correlates of alcohol dependence in adult prisoners vary according to Indigenous status

Objective : To estimate the prevalence and identify independent correlates of alcohol dependence among Indigenous and non‐Indigenous adult prisoners in Queensland. Methods : A confidential, cross‐sectional survey of 1,155 adult prisoners (n=274 Indigenous, n=881 non‐Indigenous) in seven adult prisons in Queensland. The usual alcohol consumption in the year before prison was assessed using the Alcohol Use Disorders Identification Test (AUDIT); scores ≥20 are considered consistent with alcohol dependence. Results : Indigenous prisoners were significantly more likely than non‐Indigenous prisoners to report patterns of alcohol consumption consistent with dependence. Separate multivariable analyses revealed different independent correlates of alcohol dependence according to Indigenous status. Among Indigenous prisoners, significant independent correlates of alcohol dependence included income below the poverty line and daily cannabis use before incarceration. Daily heroin use and history of injecting drug use were protective. Among non‐Indigenous prisoners, significant independent correlates included history of mental illness or self harm, and daily tobacco or cannabis use before incarceration. Older age and daily heroin use before incarceration were protective. Conclusions and Implications : The prevalence of risky alcohol use and dependence is high in Australian prisoner populations, particularly among Indigenous prisoners. Risk factors for alcohol dependence differ according to Indigenous status, indicating that separate, culturally appropriate interventions to reduce alcohol‐related harm for Indigenous prisoners may be required.     

Drug use in prisons in Kyrgyzstan: a study about the effect of health promotion among prisoners

In Kyrgyzstan the prevalence of injecting drug behaviour is among the highest found throughout the world. Health promotion training, improved health care and needle/syringe exchange (NSE) programmes have been shown to decrease risk behaviour among injecting drug users. In Kyrgyzstan, an intervention study with training of prison staff and prisoners was performed in one prison. Before and after the training, a random selection of the prisoners answered a questionnaire about drug use, risk behaviour and health care. The survey was carried out in both the intervention prison and in a reference prison. The number of drug users, the use of drugs and risk behaviour were improved significantly within half a year and, especially, the injection and use of drugs decreased in the intervention group. The study clearly shows that increased focus, improved healthcare and training of prisoners and staff on drug use and harm reduction can reduce both use of drugs and risk behaviour.     

Incidence and risk for acute hepatitis C infection during imprisonment in Australia

To determine hepatitis C incidence and the demographic and behavioural predictors in seronegative drug injecting prisoners. Prisoners in New South Wales, Australia who: were aged 18 years and over; reported IDU; had been continuously imprisoned; had a documented negative HCV antibody test result in prison in the last 12 months; provided written informed consent. Subjects were interviewed about their demographic characteristics and detailed risk factors for transmission prior to, and since, imprisonment. A blood sample was collected to screen for HCV antibodies by ELISA and RNA by PCR. Of 253 inmates recruited, 120 were continuously imprisoned and included in this analysis. Sixteen acquired HCV infection indicating an incidence of 34.2 per 100 person years (CI: 19.6–55.6). Risk factors for transmission included prior imprisonment, methadone treatment and greater than 10 years of education. Although the frequency of injecting was reduced in prison, 33.6% continued to inject drugs, most commonly methamphetamine, and 90% of these reported sharing injecting equipment. Prison inmates were at high risk of HCV infection, despite some reduction in high-risk behaviours and access to prevention services. To prevent HCV transmission in prisons, better prevention strategies are required.     

Reconsidering the public health failings of the criminal justice system: a reflection on the case of Scott Ortiz

Throughout most of the world, the primary response to the health and social impacts of illicit drug use has been to intensify the enforcement of drug laws. The consequences of this policy approach include an unprecedented growth in prison populations and increasing concerns regarding drug-related harms within prisons and without, including increased risk of HIV and hepatitis C (HCV) infection. This has led to calls from public health and prisoner advocacy groups to prison authorities to improve health services available in the community and those available to prisoners. While considerable progress has been made with respect to the growing implementation of HIV and HCV prevention measures within some nations' prisons, the case of Scott Ortiz illuminates a new set of challenges for prisoners and their advocates as judges often have a faulty understanding of public health arguments and data. In this case we see one such instance where a judge acts in ways not rooted in sound public health evidence or practice to produce a perverse outcome that violates both sound medical and judicial objectives.     

Increasing hepatitis B vaccine coverage in prisons in England and Wales

The most frequently reported risk factor for hepatitis B infection in England and Wales is injecting drug use (38%). Since approximately 61% of injecting drug users (IDUs) had been imprisoned and less than 40% had received hepatitis B vaccine, a prison based hepatitis B vaccination programme was set up in 2001. At the 42 establishments participating in this study, all prisoners were offered vaccine at reception. Prisoners over 18 years were vaccinated using the 0, 7 and 21 days schedule and those under 18 years, using the 0, 1 and 2 months schedule. As far as possible a fourth dose was given to all after 12 months. In 2003, 14,163 prisoners received at least one dose of vaccine and altogether 26,265 doses were administered. A further 1111 prisoners reported they had already been vaccinated against hepatitis B. The median vaccine coverage rate was 17% (range 0-94%). Despite low coverage levels, the vaccination programme in prisons can be said to have vaccinated a sizable number of young, male prisoners, a group that have previously been shown to be at high risk of infection. The prisons which achieved vaccine coverage levels over 50% had designated nursing staff who ran the vaccination clinics.     

Incarceration and High-Risk Sex Partnerships among Men in the United States

Incarceration is associated with multiple and concurrent partnerships, which are determinants of sexually transmitted infections (STI), including HIV. The associations between incarceration and high-risk sex partnerships may exist, in part, because incarceration disrupts stable sex partnerships, some of which are protective against high-risk sex partnerships. When investigating STI/HIV risk among those with incarceration histories, it is important to consider the potential role of drug use as a factor contributing to sexual risk behavior. First, incarceration’s influence on sexual risk taking may be further heightened by drug-related effects on sexual behavior. Second, drug users may have fewer economic and social resources to manage the disruption of incarceration than nonusers of drugs, leaving this group particularly vulnerable to the disruptive effects of incarceration on sexual risk behavior. Using the 2002 National Survey of Family Growth, we conducted multivariable analyses to estimate associations between incarceration in the past 12 months and engagement in multiple partnerships, concurrent partnerships, and unprotected sex in the past 12 months, stratified by status of illicit drug use (defined as use of cocaine, crack, or injection drugs in the past 12 months), among adult men in the US. Illicit drug users were much more likely than nonusers of illicit drugs to have had concurrent partnerships (16% and 6%), multiple partnerships (45% and 18%), and unprotected sex (32% and 19%). Analyses adjusting for age, race, educational attainment, poverty status, marital status, cohabitation status, and age at first sex indicated that incarceration was associated with concurrent partnerships among nonusers of illicit drugs (adjusted prevalence ratio (aPR) 1.55, 95% confidence interval (CI) 1.06–2.22) and illicit drug users (aPR 2.14, 95% CI 1.07–4.29). While incarceration was also associated with multiple partnerships and unprotected sex among nonusers of illicit drugs (multiple partnerships: aPR 1.66, 95% CI 1.43–1.93; unprotected sex: aPR 1.99, 95% CI 1.45–2.72), incarceration was not associated with these behaviors among illicit drug users (multiple partnerships: aPR 1.03, 95% CI 0.79–1.35; unprotected sex: aPR 0.73, 95% CI 0.41–1.31); among illicit drug users, multiple partnerships and unprotected sex were common irrespective of incarceration history. These findings support the need for correctional facility- and community-based STI/HIV prevention efforts including STI/HIV education, testing, and care for current and former prisoners with and without drug use histories. Men with both illicit drug use and incarceration histories may experience particular vulnerability to STI/HIV, as a result of having disproportionate levels of concurrent partnerships and high levels of unprotected sex. We hypothesize that incarceration works in tandem with drug use and other adverse social and economic factors to increase sexual risk behavior. To establish whether incarceration is causally associated with high-risk sex partnerships and acquisition of STI/HIV, a longitudinal study that accurately measures incarceration, STI/HIV, and illicit drug use should be conducted to disentangle the specific effects of each variable of interest on risk behavior and STI/HIV acquisition.     

The 2004 Australian prison entrants' blood-borne virus and risk behaviour survey

OBJECTIVES: To assess the prevalence of blood-borne viruses and associated risk factors among prison entrants at seven Australian prisons across four States. DESIGN: Consecutive cross-sectional design. Voluntary confidential testing of all prison entrants for serological markers of human immunodeficiency virus (HIV), hepatitis C (HCV) and hepatitis B (HBV) over 14 consecutive days in May 2004. Demographic data and data related to risks for blood-borne virus transmission, such as sexual activity, body piercing, tattooing, and injecting drug use, were collected. RESULTS: National prevalence for HIV was 1%, hepatitis B core antibody 20%, and hepatitis C antibody 34%. Fifty-nine per cent of participants had a history of injecting drug use. Among injecting drug users, the prevalence of HIV was 1%, hepatitis C antibody 56%, and hepatitis B core antibody 27%. Forty-one per cent of those screened reported a previous incarceration. In the multivariate model, Queensland and Western Australian (WA) prison entrants were significantly less likely to test positive to HCV than those in New South Wales (NSW). Amphetamine was the most commonly injected drug in Queensland, Tasmania and WA. In NSW, heroin was the most common drug injected. In the multivariate analysis a history of injecting drug use, being aged 30 years or more, and a prior incarceration were positively associated with hepatitis C infection. For hepatitis B core antibody, age over 30 years and a history of injecting drug use were associated with an increased risk. CONCLUSIONS: The findings support the view that prisoner populations are vulnerable to blood-borne virus infection, particularly hepatitis B and C. Prisoner populations should be included in routine surveillance programs so as to provide a more representative picture of blood-borne virus epidemiology in Australia.     

Attitudes and practices regarding the use of methadone in US State and federal prisons

In the United States, vigorous enforcement of drug laws and stricter sentencing guidelines over the past 20 years have contributed to an expanded incarcerted population with a high rate of drug use. One in five state prisoners reports a history of injection drug use, and many are opiate dependent. For over 35 years, methadone maintenance therapy has been an effective treatment for opiate dependence; however, its use among opiate-dependent inmates in the United States is limited. In June 2003, we conducted a survey of the medical directors of all 50 US states and the federal prison system to describe their attitudes and practices regarding methadone. Of the 40 respondents, having jurisdiction over 88% (n=1,266,759) of US prisoners, 48% use methadone, predominately for pregnant inmates or for short-term detoxification. Only 8% of respondents refer opiate-dependent inmates to methadone programs upon release. The results highlight the need to destigmatize the use of methadone in the incarcerated setting, expand access to methadone during incarceration, and to improve linkage to methadone treatment for opiate-dependent offenders who return to the community.     

HIV in prison: what are the risks and what can be done?

Prisons are recognised worldwide as important sites for transmission of blood-borne viruses (BBVs). There are two reasons why transmission risks in prison are higher than in the community. First, in most western countries, many prison entrants have histories of injecting drug use, and thus already have high prevalences of BBVs. Second, the lack or under-supply of preventive measures (such as clean needle and syringes or condoms) in most prisons, combined with extreme social conditions, creates extra opportunities for BBV transmission. HIV prevalence in prisoners in more developed countries ranges from 0.2% in Australia to over 10% in some European nations. There are case reports of HIV being transmitted by sharing injecting equipment and sexual activity. Tattooing has been reported as a risk factor for the transmission of BBVs in prison. Access to condoms and needle and syringe programmes in prisons is extremely limited, despite success when they have been introduced. The vast majority of prison inmates are incarcerated for only a few months before returning to the community--thus they are, over the long term, more appropriately regarded as 'citizens' than 'prisoners'. Public health policy must involve all sections of the community, including prison inmates, if we are to reduce transmission of HIV and other BBVs.     

HIV infection among male prisoners in South Australia, 1989 to 1994

Abstract: The prevalence of human immunodeficiency virus (HIV) in male prisoners in South Australia from July 1989 to June 1994 was ascertained from a repeated cross–sectional study. We also compared the criminological and demographic characteristics and histories of drug use of 39 HIV–infected prisoners and a randomly selected sample of 86 uninfected prisoners admitted at the same time. The numbers of HIV–infected prisoners in prison in any month ranged from 4 to 12. Prevalence among the total prison population ranged from 0.4 per cent to 1.4 per cent, and among the subpopulation of injecting drug users from 1.25 per cent to 4.36 per cent. Many HIV–infected prisoners continued after their diagnosis to have lifestyles that resulted in imprisonment. Infected prisoners were significantly older, had spent longer in prison and were more likely to be users of heroin (OR = 13.1) and methadone (OR = 25.4) than controls. Infection with HIV among South Australian prisoners has been continuous since at least the mid–1980s. The recidivism among many of the infected prisoners contributes to the variation in prevalence but also raises concerns about their management. Greater effort to minimise the recidivism of the HIV–infected prisoners could reduce the prevalence of HIV in the prison population. (Aust N Z J Public Health 1997; 21: 572–6)     

Surveillance of HIV infection and related risk behaviour in European prisons. A multicentre pilot study

BACKGROUND: In order to demonstrate the feasibility of human immunodeficiency virus (HIV) infection and related risk behaviour surveillance in European prisons, a multicentre pilot study was undertaken. METHODS: A cross-sectional survey was carried out in six European prisons (France, Germany, Italy, The Netherlands, Scotland and Sweden). Inmates were invited to complete a self-administered and anonymous questionnaire and to give a saliva sample in order to test for HIV antibodies. RESULTS: Eight hundred and forty-seven out of 1,124 inmates participated in the survey (response rate 75%). Saliva from 817 inmates (73%) was collected and processed for HIV antibodies. Twenty-seven per cent reported that they had ever injected drugs and 49% of these reported they had injected whilst in prison. Eighteen per cent of inmates reported that they had been tattooed whilst in prison, which was found to be higher among injecting drug users (IDUs). One and sixteen per cent reported that they had ever had homosexual and heterosexual intercourse in prison respectively. The HIV prevalence among IDUs was 4% (versus 1% among non-IDUs) (p = 0.02). The proportions of inmates previously tested for hepatitis C and vaccinated against hepatitis B were 24 and 16% respectively. CONCLUSION: This survey demonstrates the feasibility of cross-sectional surveys in European prison inmates and highlights the importance of surveillance of HIV prevalence and related risk behaviour among inmates. The continuing high HIV prevalence and potential for HIV spread in prisons should encourage decision makers in implementing or enhancing harm reduction and education programmes and substance abuse treatment services in prison.     

Barriers to retention in methadone maintenance therapy among people who inject drugs in Bangkok,Thailand: a mixed-methods study

Background

Methadone maintenance therapy (MMT) is a mainstay for treating opioid use disorder and preventing and managing HIV among people who inject drugs (PWID). While previous research suggested low dosing of methadone and high rates of discontinuation of MMT among PWID in Thailand, little is known about patients’ lived experiences with MMT in this setting. Therefore, we conducted a mixed-methods study to examine barriers to retention in MMT among PWID in Bangkok, Thailand, with particular attention to methadone dosing.

Methods

Bivariate statistics were used to analyze quantitative survey data collected from methadone-treated PWID between July and October 2011. Qualitative data collected through semi-structured interviews with 16 methadone-treated PWID between July 2011 and June 2012 were analyzed thematically, with a focus on individual-level, social-structural, and environmental barriers to accessing MMT.

Results

Among 158 survey participants, a median dosage of methadone was 30 mg/day (interquartile range 20–50). Of these, 15.8% reported having acquired street methadone due to low prescribed dosages of methadone and 19.0% reported recent syringe sharing. Qualitative interview data indicated some methadone provider-related barriers, including discouraging patients from using methadone due to it being a Western medicine, difficulty negotiating higher doses of methadone, and abrupt dose reductions without patient consultation (involving the provision of non-medicated “syrup” in some cases). Social-structural and environmental barriers to optimal MMT access included intense police surveillance of methadone clinics; and frequent incarceration of PWID and a lack of access to methadone in prisons.

Conclusions

Among our sample of methadone-treated PWID, methadone dosages were suboptimal according to the international guidelines. Poor adherence to international guidelines for opioid agonist therapies, aggressive law enforcement, and a lack of methadone in prisons need to be addressed to optimize MMT and reduce harms associated with untreated opioid use disorder in Thailand.

     

Children of prisoners: a growing public health problem

OBJECTIVES: To estimate the number and proportion of children in New South Wales affected by parental incarceration, and to describe the health impact of punitive incarceration on the children of prisoners. METHODS: In 2001, NSW Corrections Health Service conducted a cross-sectional survey of prison inmates randomly selected from each of the 29 prisons in NSW, representing 11% of male and 30% of female inmates in the State. The survey included questions regarding parental status and number of children. A population model was developed, which incorporated increases in the prison population and recidivism, to estimate the number of children under 16 years of age in NSW ever having experienced parental incarceration. RESULTS: In 2001, there were approximately 14,500 children under the age of 16 years in NSW who experienced parental incarceration during the year. It is estimated that in 2001 there were 60,000 children under 16 years in NSW who had ever experienced parental incarceration in their lifetime, representing 4.3% of all children and 20.1% of Indigenous children. CONCLUSIONS: The number of children who have experienced parental incarceration is significant in NSW and across Australia. Indigenous children are much more likely to experience parental incarceration than non-Indigenous children. IMPLICATIONS: Children of prisoners are at high risk of negative health outcomes and are themselves at an increased risk of offending later in life. The needs of these children must be recognised and policies introduced to reduce the adversities they face. The social, politico-legal and economic conditions that are contributing to the continuing rise in incarceration rates must be recognised, and measures must be taken to reduce this trend.     

Methadone maintenance treatment and HIV risk-taking behaviour among injecting drug users in Berlin.

STUDY OBJECTIVE: To determine whether methadone maintenance treatment (MMT) is effective in reducing the levels of HIV risk-taking behaviour (borrowing and lending of injection equipment, irregular condom use) among injecting drug users (IDUs), and to identify independent predictors of the borrowing of used syringes. DESIGN: Cross sectional study of IDUs in MMT and not in MMT, using standardised interviews for collection of sociodemographic and behavioural data, and laboratory tests for detecting HIV antibodies. SETTING AND PARTICIPANTS: The 612 IDUs were recruited at different services for drug users such as treatment centres, walk in agencies, a hospital, and on the streets. MAIN RESULTS: Of all IDUs, 41% had borrowed and 34% had passed on used injection equipment in the previous six months. In univariate analysis, IDUs receiving MMT had injected less frequently and were significantly less likely to borrow and lend syringes. In logistic regression analysis, MMT was protective against the borrowing of syringes (adjusted odds ratio 0.36, 95% confidence interval 0.2, 0.8), but not against syringe lending nor against sexual risk behaviour (i.e., numbers of sex partners, lack of condom use). Important independent predictors of the borrowing of syringes were injecting drug use in prison, use of sedatives, and sex with another IDU in the previous six months. CONCLUSIONS: MMT may play a significant role in reducing the levels of borrowing of syringes among IDUs. However, additional prevention measures are needed which should specifically address sexual risk behaviour and target subgroups of IDUs with high levels of needle sharing, such as IDUs who have been in prison and and those who are sedative users.