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Scientific Publications

General Sequence Injection Sequence Paraphernalia Topics Year, Country & WebLink Short Summary Conclusion Recommendation
Before Administration Selecting Cooker Cooker Sharing cookers
  • The sharing of injection paraphernalia (including cookers and cottons) and washwater for rinsing used needle/syringes and dissolving drugs could be potential sources for secondary transmission of HIV-1. Laboratory rinses were made from needle/syringes, cottons, and cookers obtained from shooting galleries, and washwaters were obtained from shooting galleries in Miami. 
  • We detected gag and envelope gene DNA, respectively, in three (27%) and four (36%) of 11 cottons, in six (46%) and seven (54%) of 13 cookers, and in five (38%) of 13 and in 10 (67%) of 15 washwaters from shooting galleries.

These results indicate that HIV-1 might be present in contaminated cottons, cookers, and washwaters. Reduction of risks of exposure to HIV-1 among IDUs may require modification of behaviors that are ancillary to the act of injection, such as the use of common cookers, cottons, and washwater.

Cookers should not be shared.

Before Administration Selecting Cooker Cooker Proportion of Cooker Sharing

Our objective was to examine factors associated with distributive injection equipment sharing and how NSPs can help reduce distributive sharing among IDUs. Our findings show that more IDUs give away cookers than needles or other injection equipment.

More IDUs reported distributive sharing of cookers (45%) than needles (36%) or other types of equipment (water 36%; filters 29%; swabs 8%). Regression analyses revealed the following factors associated with:
  • distributing used cookers: a history of cocaine/crack injection, an Addiction Severity Index (ASI) score indicative of a mental health problem, and older than 30 years of age. 
  • giving away used water included: male, injected methadone, injected other stimulants and moved 3+ times in the past 6 months. 
  • giving away used filters included: injected cocaine/crack or stayed overnight on the street or other public place. Factors associated with giving away swabs included: an ASI mental health score indicative of a mental health problem, and HCV negative status.

Targeting prevention efforts to reduce equipment sharing in general, and cookers in particular is warranted to reduce use of contaminated equipment and viral transmission.

Before Administration Adding Acidifier Citric/Ascorbic Acid Effect of Acids on the Survival of HIV
  • Injected drugs are acidic, HIV-1 is known to be labile to acids, but its susceptibility to acids in the conditions in which illicit drugs are injected is unknown. 
  • We have combined data from ethnographic studies of injection drug use practices with laboratory virology to replicate and evaluate the effects of exposure to acids on HIV-1 viability. 
  • Short exposures to acids significantly reduced the likelihood of recovering viable HIV-1 once pH is reduced to 2.3, but acidic solutions did not totally eliminate infectious HIV-1 that might contaminate syringes or solutions being injected, even at the lowest pH tested (pH 1.7).
  • Acidification of drugs, which is required for dissolving free-base formulations of drugs, can significantly reduce but not eliminate the likelihood that syringes previously used by HIV-1-infected injection drug users infect the next injector.
  • Methamphetamines, which are manufactured under extremely acidic pHs, are unlikely to harbor viable HIV if stored or sold in contaminated injection equipment.
  • Acidification can significantly reduce but not eliminate the likelihood of HIV-1 transmission.
  • Methamphetamines are unlikely to harbor viable HIV.
Before Administration Adding Acidifier Citric/Ascorbic Acid Acidifier Introduction and Impact on IDU Attendance

We examined whether the introduction of citrate in SEPs has altered the number of heroin/crack injectors accessing SEPs, the frequency at which heroin/crack injectors visited SEPs and the number of syringes dispensed. Neither new (first seen in either six months period) nor established clients visited SEPs more frequently post citrate.

The introduction of citrate did not negatively affect SEP attendance. Longitudinal attenders' visited SEPs more frequently post citrate, providing staff with greater opportunity for intervention and referral.

Introduction of acidifier increase clients’ frequency visit.

Before Administration Heating and Dissolving Lighter Heating temperature, duration, and inactivation of HIV-1

In response to concerns about risk of HIV-1 transmission from drug injection paraphernalia such as cookers, ethnographic methods were used to develop a descriptive typology of the paraphernalia and practices used to prepare and inject illegal drugs. Observational data were then applied in laboratory studies in which a quantitative HIV-1 microculture assay was used to measure the recovery of infectious HIV-1 in cookers.

HIV-1 survival inside cookers was a function of the temperature achieved during preparation of drug solutions; HIV-1 was inactivated once temperature exceeded, on average, 65ºC. Although different types of cookers, volumes, and heat sources affected survival times, heating cookers 15 seconds or longer reduced viable HIV-1 below detectable levels.

  • Temperature should exceed, on average,  65ºC to inactivated HIV-1.
  • Cookers should be heated 15 seconds or longer to reduced viable HIV-1 below detectable levels.
Before Administration Filtering Cotton Pellet Sharing cookers, cottons, and washwater
  • The sharing of injection paraphernalia (including cookers and cottons) and washwater for rinsing used needle/syringes and dissolving drugs could be potential sources for secondary transmission of HIV-1. Laboratory rinses were made from needle/syringes, cottons, and cookers obtained from shooting galleries, and washwaters were obtained from shooting galleries in Miami. 
  • We detected gag and envelope gene DNA, respectively, in three (27%) and four (36%) of 11 cottons, in six (46%) and seven (54%) of 13 cookers, and in five (38%) of 13 and in 10 (67%) of 15 washwaters from shooting galleries.

These results indicate that HIV-1 might be present in contaminated cottons, cookers, and washwaters. Reduction of risks of exposure to HIV-1 among IDUs may require modification of behaviors that are ancillary to the act of injection, such as the use of common cookers, cottons, and washwater.

Filtering cottons should not be shared.

Before Administration Choosing Syringe Syringe Syringe Re-use Behavior and Housing

Systematic reviews and meta-analyses show that needle exchange programs reduce HIV and HCV transmission for IDUs but far less is known about the injection practices of IDUs enrolled in these programs. This study adopts a mixed methods approach to quantify high-risk injection practice patterns among IDUs enrolled in a needle exchange program and gather qualitative data to understand underlying injection behaviour rationales and patterns.

Univariate analysis showed all respondents reporting at least one high-risk practice within the past month. Multivariate logistic regression analysis using input from the clientele confirmed the importance of housing status as a determinant of injection practices.

The importance of housing status points to the need to combine needle exchange and appropriate housing.

Before Administration Choosing Syringe Low Dead Space Syringe Decreasing HIV Transmission Risk with LDSS

HDSS syringe compared to LDSS carries a larger blood volume being transferred after water rinses. HDSS use could be associated with an increase in transmission risk compared to LDSS.

Indirect evidence suggests that encouraging HDSS users to use LDSS could be an HIV prevention strategy. 

Use low dead-space syringes.

Before Administration Choosing Syringe Low Dead Space Syringe HIV & HCV Transmission and Low/High Dead Space Syringes

This study examines the association between using and sharing high dead-space syringes (HDSSs) - which retain over 1,000 times more blood after rinsing than low dead-space syringes (LDSSs) - and prevalent HIV and hepatitis C virus (HCV) infections among injecting drug users (IDUs).

  • A history of using and sharing an HDSS were significantly more likely to be HIV-positive than participants that had never shared any type of syringe and never used an HDSS.
  • The interaction between a history of syringe-mediated drug sharing and using an HDSS was significantly associated with HCV infection.
Similar to sex risk behaviors, the risks of HIV transmission associated with direct and indirect syringe sharing are influenced by a number of factors, and the protective role of LDSSs may be analogous to the role of male circumcision or antiretroviral therapy.

LDSS should be prefered to HDSS.

Before Administration Choosing Syringe Low Dead Space Syringe Factors Affecting Needle and Syringe Preference, Gender

IDUs, a group at elevated risk for HIV transmission, use syringes manufactured in two styles, one of which (the integral cannula type) retains substantially less blood after intravenous use than the other (the detachable needle type). In this report, we examine some of the factors associated with use of syringes with detachable needles among 500 IDUs in San Antonio, Texas, using data from epidemiological surveys, ethnographic studies, and historical observations.
 

Ethnographic data suggested the following perceived benefits with detachable needle syringes :
  • Removing the needle while preparing and drawing up the drug reduces the probability of dulling it by accidentally jamming it into the spoon or cooker. 
  • A drug solution can be drawn into a syringe more rapidly through the larger opening of the cannula than through the much smaller opening of a needle. 
  • If a needle clogs during an injection, it can be replaced easily on a syringe with a detachable needle. In an integral cannula syringe, the plunger must be removed and the solution must be dumped back into a cooker before the needle can be unclogged.
  • Integral cannula syringes were used when they started injecting, 
  • The smaller dead space used substantially less drug. 
  • Overwise, many drug users preferred not to booting because it increases the risk of losing the vein and missing the injection (accidentally moving the tip of the needle out of the vein and injecting some of the solution into tissue), which results in bruising and  possible abcess. 
Needle gauge is another factor that influences. Many IDUs, particularly those who began injecting more recently and still have good veins, prefer the smaller 28 gauge needles because they tend to be less painful to use and do less damage to veins. 
 
Conversely, some IDUs who have been injecting longer and have poor veins may prefer the larger 25 gauge needles because they do not clog as easily, and they can penetrate thick scar tissue without bending. 
In cities where syringes are difficult to obtain prefer the larger gauge needles because they are more durable. Fluid can be drawn into larger gauge needles and expelled much more rapidly than from smaller gauge needles.

Males reported detachable needle use more commonly (43%, OR=1.37) than females (26%).

Harm reductsion programs should take these factors into consideration while selecting paraphernelia to be distributed and promoting low dead space syringes.

During Administration Administrating Syringe Survival of HIV-1 in syringes : effects of temperature

In a previous paper we demonstrated that HIV-1 survival in syringes was strongly associated with the volume of blood remaining and with the duration of storage at room temperature. The current study was performed to determine the effects of storage temperature upon the survival of HIV-1 inside syringes.

  • At 4°C, 50% of all syringes contained viable HIV-1 at 42 days of storage, the longest storage duration tested.
  • At room temperature (20°C), the last day that syringes with 2 mL of infected blood were positive was Day 21, and viable HIV-1 was recovered from 8% of syringe.
  • The last day on which syringes with 20 mL were positive was Day 42, and viable HIV-1 was recovered from 8% of syringes.
  • Above room temperature (27, 32, and 37°C), the likelihood of encountering syringes with viable HIV-1 when periods of storage exceeded 1 week decreased to less than 1%.
     

HIV-1 survives longer at 4°C than at room temperature and longer at at room temperature than above 27°C. Reusage of syringe should be prevented irrespective of the temperature.

During Administration Administrating Syringe Gender and Sexual/Injection Risk Behavior

Female IDUs represent a large proportion of persons infected with HIV in the United States, and women who inject drugs have a high incidence of HBV and HCV infection. Therefore, it is important to understand the role of gender in injection risk behavior and the transmission of blood-borne virus. We compared self-reported risk behavior between 584 males and 260 female participants from cross-sectional baseline data. 

Females were 
  • significantly younger than males and were more likely to engage in needle borrowing, ancillary equipment sharing, and being injected by someone else. 
  • more likely than males to report recent sexual intercourse and to have IDU sex partners. 
  • In logistic regression models for borrowing a used needle and sharing drug preparation equipment, increased risk in females was explained by having an injection partner who was also a sexual partner. 
  • Injecting risk was greater in the young female compared to male IDUs despite equivalent frequency of injecting. 
  • Overlapping sexual and injection partnerships were a key factor in explaining increased injection risk in females. 
  • Females were more likely to be injected by another IDU even after adjusting for years injecting, being in a relationship with another IDU, and other potential confounders.
 
Interventions to reduce sexual and injection practices that put women at risk of contracting hepatitis and HIV should be promoted.
During Administration Administrating Syringe Social Factors Related to Sharing and Gender

The study of social networks has become an increasingly utilized method of examining the relationship between IDUs' social environment and risk of HIV. This study examined relational aspects of two IDUs within a single social network as they relate to sharing syringes. Analyses were performed separately for male and female participants in an effort to understand gender differences in social aspects of syringe sharing. 

Among this sample, women shared syringes with a significantly higher percentage of injecting partners compared to men. 
In separate multilevel logistic regression models, significant variables associated with males' and females' syringe sharing were: 
  • sharing drugs daily with female injecting partners, 
  • injecting partners' provision of drugs 
when indexes' were 
  • withdrawing, 
  • being sexual partners, 
  • and injecting partners' injecting speedballs. 
Factors associated with male injecting dyads sharing of syringes were: being kin, injecting partners' injection of heroin and daily drug use, and drinking alcohol together.

Prevention and health education programs should provide appropriate specific actions depending on gender.

During Administration Administrating Syringe Frontloading

To determine whether frontloading (i.e., syringe-mediated drug-sharing) is a risk factor for HIV, HBV and HCV infection among IDU.

Having practised frontloading more than 100 times was significantly associated with HIV infection, and HCV infection, but not with HBV infection. In communities where sterile injection equipment is readily available, and IDU have substantially reduced their overall levels of needle-sharing, the practice of frontloading appears to be a major risk factor for infections by blood-borne viruses among IDU. 

Prevention activities should specifically address frontloading as a risky behaviour.

During Administration Administrating Syringe Backloading and HIV risk factor

In syringe-mediated drug-sharing (backloading), IDUs use their syringes to mix drugs and to give measured shares to other IDUs by squirting drug solution into the syringes of other IDUs. Backloading has been discussed as a potential HIV risk factor, but its role as an HIV transmission route has not been established empirically.

Backloading remained positively and significantly associated with HIV seropositivity in stepwise logistic regression, and in a series of simultaneous logistic models controlling for sociodemographic variables and for sexual and drug risk variables.Backloading can be a route of HIV transmission among IDUs. Many IDUs who avoid other high-risk drug-injection practices may overlook the risk of backloading. HIV prevention programs should warn IDUs against syringe-mediated drug-sharing and work together to develop ways to avoid it.

Avoid backloading.

After Administration Cleaning Equipment Other Sterile Water Sharing washwater from rinsing
  • The sharing of injection paraphernalia (including cookers and cottons) and washwater for rinsing used needle/syringes and dissolving drugs could be potential sources for secondary transmission of HIV-1. Laboratory rinses were made from needle/syringes, cottons, and cookers obtained from shooting galleries, and washwaters were obtained from shooting galleries in Miami. 
  • We detected gag and envelope gene DNA, respectively, in five (38%) of 13 and in 10 (67%) of 15 washwaters from shooting galleries.

These results indicate that HIV-1 might be present in contaminated cottons, cookers, and washwaters. Reduction of risks of exposure to HIV-1 among IDUs may require modification of behaviors that are ancillary to the act of injection, such as the use of common cookers, cottons, and washwater.

Washwater from rinsing should not be shared.

After Administration Cleaning Equipment Bleach Efficiency of bleach against HIV

Bleaching of syringes has been advocated to prevent HIV-1 transmission among injection drug users (IDUs). We applied a sensitive HIV-1 microculture assay to determine the effectiveness of bleach in disinfecting syringes contaminated with HIV-1.

This study demonstrates that in a laboratory environment undiluted bleach is highly effective in reducing the viability of HIV-1 even after minimal contact time. However, 
  • it did not reduce the HIV-1 recovery to zero,
  • 3 washes with water were nearly as effective as 1 rinse with undiluted bleach in reducing the likelihood that contaminated syringes harbored viable HIV-1.

IDUs should be encouraged through harm reduction interventions to clean their syringes, preferably with undiluted bleach. This will not reduce the HIV-1 recovery to zero.

After Administration Cleaning Equipment Bleach Concentrations of bleach on in-vitro HIV-1 replication and potential transmission

The use of bleach as a disinfectant for drug injection equipment was recommended early in the HIV-1/AIDS epidemic. Epidemiological studies have challenged it.

  • However, in vitro HIV-1 coculture studies have shown that a high concentration of bleach is an effective cytotoxic and potentially virucidal agent.
  • But low concentrations of oxidants likely to remain in cleaned equipment despite rinsing have been shown to enhance tissue inflammation, in vivo, as well as HIV-1 replication in vitro.
  • And studies have shown that despite vigorous cleaning, microaggregates of residual blood remained in bleach-cleaned blood-contaminated syringes.
  • Hypothetically, oxidant effects of the residual bleach in the bleach-cleaned syringes could enhance the possibility of infection by remaining HIV-1 contained in a contaminated syringe.

Likelihood of an injection drug user contracting HIV-1 through the sharing of a bleach-cleaned blood-contaminated syringe may be increased by the cotransmission of residual bleach and its localized tissue-inflammatory effects; however, this has not been statistically proven in epidemiological studies.

Bleach is not the ideal mean to prevent HIV transmission possibility in cleaning injection equipment.

After Administration Cleaning Equipment Bleach Impact of different cleaning solutions and concentration

Bleaching of syringes has been advocated to prevent HIV transmission among IDUs. IDUs are reported to use household products to disinfect syringes instead of bleach. To test their disinfection efficacy, we performed syringe-rinsing simulations with a range of agents used by IDUs trying to disinfect their syringes.

  • No viable HIV-1 was recovered from syringes rinsed with bleach diluted 1:10.
  • Bleach stored at 37 degrees C and rubbing alcohol performed better than water and the other liquids tested, but less well than bleach 1:10.
  • Rinsing syringes with the other liquids was similar to rinsing with water alone.
  • Increasing the rinsing volume did not always increase the effect of rinsing, but the addition of a second rinse consistently increased rinsing efficacy.
  • Bleaching remains the most effective disinfectant among those tested. 
  • It is important that IDUs learn the proper techniques for bleach storage and syringe decontamination.
  • Other household products are not effective disinfectants and should be avoided.
After Administration Disposing Equipment Syringe Risk of Transmission via Needlestick

Discarded needle syringes create considerable anxiety within the community, but the extent of needlestick injuries and level of blood-borne virus transmission risk is unclear. We have undertaken a review of studies of blood-borne virus survival as the basis for advice and management of community needlestick injuries.

  • HBV, HCV, and HIV can all survive outside the human body for several weeks, with virus survival influenced by virus titer, volume of blood, ambient temperature, exposure to sunlight and humidity. 
  • HBV has the highest virus titers in untreated individuals and is viable for the most prolonged periods in needle syringes stored at room temperature. 
However, prevalence of HBV and HIV are only 1-2% within the Australian IDU population. In contrast, prevalence of HCV is 50-60% among Australian IDUs and virus survival in needle syringes has been documented for prolonged periods.
There have been no published cases of blood-borne virus transmission following community needlestick injury in Australia.
The risk of blood-borne virus transmission from syringes discarded in community settings appears to be very low.

 Despite this, procedures to systematically follow up individuals following significant needlestick exposures sustained in the community setting should be developed.

After Administration Substituting Methadone Seroprevalence Among IDUs on Methadone Treatment

Opioid drug users on methadone treatment are routinely offered voluntary screening for HIV, HBV and HCV. Data on uptake and outcome of anti-HIV, anti-HBC, and anti-HCV screening among Opioid DUs receiving methadone were obtained from Amsterdam from 2004 to 2008 and Heerlen from 2003 to 2009. Annual screening uptake for HIV, HBV and HCV varied from 34 to 69%, depending on disease and screening site. Of users screened, 2.5% were HIV-positive in Amsterdam and 11% in Heerlen; 26% were HCV-positive in Amsterdam and 61% in Heerlen. Of those screened for HBV, evidence of current or previous infection (anti-HBC) was found among 33% in Amsterdam and 48% in Heerlen. In Amsterdam, 92% were fully vaccinated for HBV versus 45% in Heerlen.

On average, more than half of the ODUs in methadone care were screened for HIV, HBV and HCV.
Screening data indicate that HBV vaccination uptake was rather high.
While the HIV prevalence among these ODUs was relatively low compared to other drug-using populations, the high HCV prevalence among this group underscores the need to expand annual screening and interventions to monitor HIV, HBV and HCV in the opioid drug-using population.

Participation in both NSPs and methadone programs is associated with decreased risk of acquiring HIV and HCV among people who have ever injected drugs. Methadone services should be promoted.

After Administration Safer Sex Male Condom Gender and Sexual Risk Behavior

Female IDUs represent a large proportion of persons infected with HIV in the United States, and women who inject drugs have a high incidence of HBV and HCV infection. Therefore, it is important to understand the role of gender in injection risk behavior and the transmission of blood-borne virus. We compared self-reported risk behavior between 584 males and 260 female participants from cross-sectional baseline data. 

Females were 
  • more likely than males to report recent sexual intercourse and to have IDU sex partners.
  • In logistic regression models for borrowing a used needle and sharing drug preparation equipment, increased risk in females was explained by having an injection partner who was also a sexual partner. 
  • Overlapping sexual and injection partnerships were a key factor in explaining increased injection risk in females. 
  • Females were more likely to be injected by another IDU even after adjusting for years injecting, being in a relationship with another IDU, and other potential confounders. 

Interventions to reduce sexual and injection practices that put women at risk of contracting hepatitis and HIV are needed.

After Administration Safer Sex Male Condom Relationship Characteristics and Condom Use and Sex Partners
Few studies have examined sexual risk behaviors among IDUs in the context of their primary sexual relationships. The aim of this study is to examine characteristics of sexual partners associated with inconsistent condom use among a sample of 703 cocaine and opiate users. The current study examines relationship characteristics between drug users and their sexual partners (n=1003). 
  • Some of the study participants had more than one sexual partner, accounting for the greater number of sexual pairs than study participants. 
  • Study participants reported using multiple drugs (56% injected, 48% sniffed heroin, and 48% smoked crack) and that 70% of their sexual partners also used heroin and/or cocaine. 
  • 40% reported consistent condom use in the past 3 months. 
In multiple logistic regression, characteristics associated with consistent condom use were: 
  • the drug user being HIV infected; 
  • not living with their sexual partners; 
  • and not being financially interdependent. 
Previous research has demonstrated lower rates of condom use with main compared with casual and exchange partners. Primary sexual partners provide a sense of stability and introducing condoms may not be desirable or realistic. 

HIV prevention programs that target drug users should focus on the benefits, such as trust and a sense of security, and risks of not using condoms in primary relationships. Programs should also focus on enhancing communication and negotiation skills through targeting individuals as well as couples.

After Administration Safer Sex Male Condom Gender and Sexual Risk within IDUs

Female were more likely than male IDU :

  • to have had a steady sexual partner (68% versus 45%),
  • to have had an IDU steady sexual partner (47% versus 15%)
  • and to have exchanged sex for money or drugs in the last 6 months (26% versus 2%).


There were no gender differences in injecting risk behaviours. HIV prevalence was 39% in women and 32% in men. HIV prevalence among female IDU who reported having exchange sex for money or drugs was 53.3%. The prevalence of HCV was 67% and 74% in female and male IDU, respectively.

There are differences in sexual risk behaviours between male and female IDU. The higher prevalence of HIV among women than among men, together with a lower prevalence of HCV, provides evidence that sexual transmission of HIV is more important among female IDU.

Prevention and health education programs should provide appropriate specific actions depending on gender.
After Administration Safer Sex Male Condom MSM IDUs and Injecting and Sexual Transmission Risks

Although transmission of HIV among IDUs has been limited since the 1980s, IDUs and MSM have higher HIV and HCV prevalences than the general population. MSM who are also IDUs may therefore have a higher risk of infection than male IDUs who only have sex with women.

MSM-IDUs had a higher prevalence of HIV and of HCV and were about four times more likely to have unprotected sex with multiple partners. Among those who injected in the 4 weeks prior to participation, the MSM-IDUs had a higher level of needle/syringe sharing suggesting elevated risk from injecting and possibly sexual transmission. 

Public health interventions should specifically target at MSM-IDUs.

After Administration Safer Sex Female Condom WSW IDUs, Prevalence, and Transmission Risks

Women injection drug users who have sex with women (WSW IDUs) constitute 20% to 30% of American women IDUs. Compared with other women IDUs, WSW IDUs have higher HIV prevalence and incidence rates and a greater likelihood of engaging in high-risk injection and sexual practices with men. 

Compared with other young women IDUs, WSW IDUs were more likely to have been institutionalized or homeless, to have engaged in riskier behaviors, to have had high-risk sexual and injection networks, and to have been anti–hepatitis B virus–positive. In high-HIV-prevalence sites, they were more likely to have been infected with HIV. These differences cannot be accounted for by their greater involvement in sex work.
WSW IDUs were more likely :

  • To have positive test results for HBV (but not for hepatitis C virus, chlamydia, or gonorrhea) and were more likely to be infected with HIV in high-prevalence.
  • To engage in high-risk behaviors (receptive syringe sharing, sharing rinse water, and sex trading) and reported having more male sexual partners. 
  • To report having unprotected sex with MSM; having sex with an IDU or someone they knew or thought was infected with HIV; and injecting drugs with MSM, WSW IDUs, someone at least 5 years older, and someone who “had hepatitis.” 
  • To have ever injected drugs with MSM in low-HIV-prevalence, but not high-HIV-prevalence, sites.

Prevention and health education programs should provide appropriate specific actions depending on gender and sexual orientation.