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Archival Content: 1999-2005

HIV Prevention Among Drug Users:
A Resource Book for Community Planners & Program Managers

HIV Behavioral Risks Among Drug Users

Drug users face multiple opportunities for HIV exposure through their drug use, sexual, and social behaviors. Understanding these behaviors will allow prevention planners and managers to identify reliable information related to the behaviors, current populations who are at high risk for HIV infection, and populations who are most in need of prevention interventions. Table 2.1 lists these practices and behaviors.

Table 2.1: High-Risk Practices and Behaviors Among Drug Users
Injection Drug-use Practices*

Type of drug injected

  • speedball (heroin and cocaine combined; highest correlation with HIV transmission)
  • heroin
  • cocaine (frequency of injection)

Sharing of equipment

  • direct sharing of syringe
  • indirect sharing
    • Sharing water, cooker, or cotton
    • Using used syringe plunger to stir drug solution
    • Backloading, frontloading
    • Recycling used cottons to extract residual drugs
    • Using unclean rinse water to mix with drug
    • Using dirty syringe to draw up water or measure shared drugs
    • Returning a portion of the drug solution to the cooker from a used syringe
    • Sharing unknowingly (IDU partner or spouse loans out works to another IDU)

  • using crack as well as injecting drugs
Non-injection Drug Practices

Multiple sexual risk behaviors (see below)

Sexual Behaviors

Unprotected sex

  • receptive anal intercourse
  • insertive anal intercourse
  • vaginal intercourse
  • oral sex

Multiple partners
Trades of sex, money, and drugs
Lack of treatment for STDs (especially ulcerative lesions)

*NOTE:These practices are defined and described more fully later in PART 2 in the section entitled "Direct and Indirect Transmission of HIV Risk Through Sharing of Injection Equipment" and in the BOX on "Drug Use Practices and Risk for HIV Transmission."

Injection Drug Use Practices

Injection drug users are the second largest subgroup of persons with AIDS in this country (CDC, 1996). Several factors contribute to the IDU's level of risk. These include the type of drug injected, frequency of injection, availability of sterile injecting equipment, method of preparing the drug for injection, and the location chosen for the process. Because each one of these behaviors also presents an opportunity for intervention, it is essential to understand the full constellation of specific injection drug-using behaviors if planning groups are to support successful interventions. For example, if IDUs inject with sterile syringes and do not share equipment, their risk of drug-related HIV infection is low. However, IDUs who use bleach to clean their syringes still incur risk if they continue to use virus-contaminated rinse water in the drug solution. The following section provides a general overview of HIV transmission risks associated with drug use, a discussion of the processes of procuring, mixing, and injecting drugs, and a discussion of high-risk sexual behaviors common among drug users.

Figure 2.1: Equipment Used to Prepare and Inject DrugsDirect and Indirect Transmission of HIV Through Sharing of Injection Equipment

Injecting a drug like cocaine or heroin requires several pieces of equipment that are commonly referred to as a "set of works." Figure 2.1 displays some of the most frequently used components for preparing and injecting drugs. Exhibit D discusses these components in detail.

Through the shared use of drug equipment, HIV can be transmitted from an infected IDU to an uninfected person either "directly" or "indirectly." Transmission may occur directly when someone injects a drug with a syringe that another person has used and contaminated with HIV. Indirect transmission happens when the drug solution in a syringe is contaminated in the process of mixing or distribution.

Exhibit D: Drug Use Practices and Risk for HIV Transmission

Using a Drug Runner

IDUs often pool their money and make a single drug purchase in an effort to offset the cost of heroin or cocaine and to avoid the risk of arrest and/or imprisonment in buying these drugs. A drug "runner" who purchases drugs for a group of users may become a direct or indirect link for the transmission of HIV to different groups of IDUs. Runners may travel to outside communities or unfamiliar contact groups to negotiate a drug purchase. On these buying "runs," they may also take part in risky activities, such as testing ("tasting") drugs, using borrowed injection equipment, or having casual sex with those they come into contact with.

If drug buyers pay the runner with a portion of the drugs bought, the runner may subsequently inject with other members of the group once the drug has been distributed and prepared. The runner may become infected through this process and, in turn, infect others within this own network of IDUs and sex partners. If already infected with HIV, runners may transmit the virus through syringe sharing or sexual activity with members of different groups.

Using Contaminated Syringes and Drug Preparation Equipment Bottle Top

Injection drugs are usually sold in dry powder form, which must be mixed with water and sometimes heated before being injected. This is typically done in a spoon or a bottle cap, called the "cooker." The drug and water solution is then drawn into a syringe through a filter or a "cotton," which prevents small particles in the solution from clogging the syringe.

IDUs usually inject the drug into a vein in their arm or hand. The arm veins of long-time users often are damaged from repeated injections; when this is the case, veins in other parts of their body are used. Before injecting, the IDU must first determine whether the needle has been inserted into a vein. To do so, he or she pulls back the syringe plunger to see if blood enters the syringe. This is called "registering."

If blood registers in the syringe, the needle is in a vein. Registering contaminates the entire syringe: needle, hub, barrel, and plunger (Normand et al., 1995).


Once the user inserts the needle into a suitable vein, the drug is injected directly into it. To ensure injecting all of the drug, the IDU may pull the plunger back several times, drawing blood into the syringe each time, and then re-injecting it into the vein. This technique, called "booting," results in a higher volume of residual blood in the syringe (Normand et al., 1995).

HIV survives in the residual blood in used syringes, even if the syringe has been rinsed with water. This was demonstrated in a 1990 study, in which used needles were tested for HIV. Of the needles with visible blood, 20 percent tested seropositive; of those with no visible blood, just over five percent were seropositive (Chitwood et al., 1990). A follow-up study in 1992 found that over half of the syringes with visible blood were HIV positive (McCoy et al., 1994).

After injecting the drug, the user rinses the syringe with water to prevent the clotting of any blood remaining in the syringe. Not only does this not disinfect the syringe of HIV or hepatitis viruses, it also contaminates the rinse water. Drug injection may take place in locations with little access to water, so rinse water may be infrequently changed, and therefore, become increasingly contaminated with eachcup use. "Moreover, rinse water is commonly used not only for rinsing, but also for the mixing of the drug solution to be injected....It is the injection of this contaminated water that poses the greatest threat for HIV transmission, especially in the case of cocaine injection, because cocaine is water soluble and does not always require heating in a cooker to be dissolved" (Normand et al., 1995, p. 27).

The injection of cocaine presents greater risk to the IDU than injection of other drugs or of heroin alone. Cocaine injectors require more injections per day, multiplying the number of opportunities for HIV exposure (depending on injection practices) over those faced by heroin users. The injection of speedball also has been highly correlated with HIV infection (Battjes et al., 1994). In one study, speedball users were one-and-a-half times more likely to be seropositive than were those injecting heroin (Koblin et al.,1990). Another study found that the techniques used for loading syringes with speedball doubled the risk for HIV infection for the IDU (Inciardi et al., 1991).

Direct sharing

Even with the advent of AIDS, the use of drug injection equipment by more than one person (multiperson use, or "sharing") continues to be practiced among injection drug users (Koblin et al., 1990; Mandell et al., 1994; Battjes et al., 1994). Sharing syringes occurs among IDU partners and people who regularly inject drugs together (drug networks) (Hartel, 1994; Williams et al., 1995). Anonymous, sequential sharing also can occur at "shooting galleries,"1 where syringes are rented out to one person after another without being disinfected (Murphy et al, 1991).2 Other factors also influence whether or not injection equipment will be shared by IDUs (see Table 2.2).

Table 2.2: Factors in Sharing Injection Equipment

Sharing drug equipment is a function of a number of interrelated factors, including:

  • demographic factors of users (e.g., age, gender, length of time using drugs, and drug treatment history)
  • the availability of drug injection equipment in the community
  • perception of the risk of arrest as a result of carrying injection equipment
  • perception of risk of infection from HIV and other infectious diseases
  • the settings in which injection occurs
  • membership in a network of injection drug users
  • the type of drug or drugs used
  • the frequency of injection
Source: Normand et al.,1995

Not all those who inject drugs do so intravenously, however. For example, injecting a drug underneath the skin ("skin popping") is a method commonly employed by those just beginning to experiment with drug injection (Inciardi et al., 1991; Kaplan, 1983). Novices may incorrectly harbor the notion that drug dependence as well as HIV transmission cannot occur by this practice. Beginners rarely have their own injecting equipment, so they frequently share another IDU's syringe.

Indirect sharing

The risks of HIV exposure with indirect sharing arise from the processes of preparing the drug for injection and dividing it among several users. After purchasing drugs, one user in the group may use his or her syringe to draw up rinse water to mix with the drug. A plunger may be used to stir the solution as it heats, and the drug may be distributed by using the measurement markers on a syringe. Drug users are at risk of HIV transmission if the water or the syringe used for distribution has been contaminated with HIV-infected blood. Table 2.3 shows the indirect sharing practices that may occur with injection drug use.

Many IDUs are unaware of the risk of transmitting HIV through sharing practices. In one study, only 7 percent of the IDUs interviewed were aware of the risks of indirect sharing, even though more than 70 percent of the injectors observed were currently involved or had already participated in an AIDS intervention (Koester et al., 1994).

Table 2.3: Indirect Sharing Practices

HIV can be transmitted indirectly among injection drug users by use of previously blood-contaminated equipment in any of the following sharing practices. None of these practices involves direct re-use of a syringe for drug injection by another user.

  • "Backloading," in which drug solution is transferred from one previously blood-contaminated syringe to another. In this case, the plunger is removed from the syringe into which the drug will be transferred. The drug mixture is then squirted into the back of the syringe.
  • "Frontloading," in which the drug solution is transferred from one previously blood-contaminated syringe to another by removing the needle on the syringe receiving the solution, and then squirting the drug into the syringe's hub or barrel. This is now relatively uncommon, since most insulin syringes used by IDUs do not have removable needles.
  • Squirting the drug solution from a previously blood-contaminated syringe into the drug mixing "cooker" or "spoon" and then drawing it into another syringe.
  • Using the plunger from a previously blood-contaminated syringe to mix the drug with water.
  • Drawing up the drug through a cotton filter that has been contaminated with HIV-infected blood.
  • Returning the drug solution from a previously blood-contaminated syringe to the shared cooker or directly to another syringe (this occurs when the user draws up more than his or her allotted share of the drug).
  • "Beating" a used cotton (or several cottons) to retrieve any drug remaining in the cotton.
  • "Kicking out a taste" by putting a part of the drug/water solution from a previously blood-contaminated syringe back into the cooker or into another IDU's syringe so that another or several other IDUs can get some of the drug.
  • Rinsing a used, blood-contaminated syringe in water that other IDUs also use to rinse their own syringes or to dissolve drugs.
  • Drawing up the water for dissolving the drug by using another injectors used, inadequately disinfected syringe.

Source: Koester et al.,1994.

High-Risk Sexual Behavior Among IDUs

Along with the knowledge of practices and risk behaviors related to drug injection, prevention planners and managers need to take into consideration the sexual risk behaviors of drug users. These include unprotected anal, vaginal, or oral sex; multiple partners; trades of money, drugs, and sex; and lack of treatment for STDs, especially those with ulcerative lesions.

Traditionally, most HIV prevention efforts for IDUs have focused primarily on lowering risk of HIV transmission by changing drug injection practices. Less attention, however, has been paid to lowering the sexual risks of HIV transmission among IDUs. In one recent survey of IDUs, at least half reported that they were not sure that condoms are effective in preventing sexual transmission of HIV and less than one-third reported using condoms (Rhodes et al., 1990). Several studies have found a strong correlation between IDUs' unsafe sexual behaviors and their risky injection practices, suggesting that IDUs who engage in one unsafe behavior are more likely to engage in others (Schilling et al., 1991; Vanichseni et al., 1993; Paone et al., 1995). All studies of risk reduction interventions for IDUs that compared changes in injection risk behavior with changes in sexual risk behavior found greater changes in injection risk behavior (Friedman et al., 1993). Overall, condoms have been found to be used more consistently by IDUs in "casual" sexual relationships than in "primary" sexual relationships and with non-injecting sex partners than with injecting sex partners (Friedman et al., 1994).

Purchase, Preparation, and Use of Crack

Figure 2.2: Typical Equipment Used to Smoke Crack Powdered cocaine, water, and baking soda are heated, forming a waxy substance known as "crack." Crack is cheaper than other illicit drugs, costing somewhere between $5 and $10 for a small bag of crack "rocks." Typically, a simple glass pipe is filled with one or two "rocks" and then lit. As the crack melts, it vaporizes and makes a crackling sound. The user then inhales the vapor. A water pipe is often used to filter impurities and cool the hot vapor. Figure 2.2 shows two types of pipes commonly used to smoke crack.

The fact that crack is relatively inexpensive, easy to use, and easy to hide makes it extremely popular. However, crack has to be used frequently and repeatedly since its effects are short-lived. As with other forms of cocaine, users can quickly become crack-dependent. Many crack abusers use the substance again and again until their money is gone. Crack users may spend from $50-$500 during a three-to four-day binge, known as a "mission," in which they consume up to 50 rocks of crack each day. During these binges, crack users often do not eat or sleep.

High-Risk Sexual Behavior Among Crack Users

Crack use is associated with high-risk sexual activities as a result of the exchange of sex for crack or money to buy crack. The circumstances under which crack is purchased, prepared, and used can influence the level of these risks. When a crack user is dependent on sex exchange to purchase or use crack, for example, the level of risk for HIV infection increases significantly. Data on the "intersecting epidemics" of crack and HIV are now emerging and help to shed light on these complex behaviors. Case Example 2.1 describes one recent study that explored this linkage in inner-city young adults.

Crack use and the sexual risks of HIV transmission

Considering cocaine's inhibitory effect on sexual functioning, it is still not clear why there is such a close association between crack use and increased sexual activity. Some theories suggest that it is the disinhibiting effect of drug use or the compulsion to use crack that prompts the sexual activity


Case Example 2.1

Intersecting Epidemics: Crack Use and Sexual Risks for HIV Infection

Young adults ages 18-29 were recruited from inner-city neighborhoods in New York, Miami, and San Francisco. The study examined 1,967 participants who were regular smokers or non-smokers of crack cocaine but who had never injected drugs. Overall, 15.7 percent of the crack smokers were positive for HIV antibodies, compared with 5.2 percent of nonsmokers. HIV prevalence was highest among women who used crack in New York (29.6 percent) and Miami (23.0 percent). In San Francisco, seroprevalence was higher among male crack users, but still substantially lower than all East Coast users and non-users.

Crack smokers of both sexes were more likely than nonsmokers to report high-risk sexual practices and a history of STDs. Female crack users were 28 times more likely to have engaged in recent, unprotected sex than were nonusers. Crack smoking appears to lead to the transmission of HIV through its association with high-risk sexual practices. Women who use crack and engage in high-risk sexual practices were found to be at nearly equal risk to that of men who have sex with men.

Edlin et al.,1994.

Three types of sexual exchanges are commonly associated with crack use (Ratner, 1993):

  • Casual exchange: a sexual exchange among crack-using acquaintances within a social setting.
  • Sex-for-money-for-crack-exchange: a commercial exchange in which crack-using prostitutes expect money but will also accept crack for use during the sexual exchange or as a "bonus."
  • Sex-for-crack-or-money-exchange: a sexual exchange made out of desperation by those whose lives are dominated by the compulsion to use crack.

All three of these types of exchanges present risks of HIV transmission, although to varying degrees.3 Since condom use is rare in these circumstances, women are exposed to the potentially infectious semen of all their male partners, who in turn, are also exposed to the semen of the women's previous male partners. In addition, men who abuse crack often have difficulty ejaculating, which leads to prolonged sexual intercourse and possible breaks and tears in the genital skin and mucosal membranes (Ratner, 1993). These breaks provide opportunities for exposure to potentially infectious genital secretions, blood, and semen. Chronic crack users also can burn their lips and tongue while using hot crack pipes, increasing the risk of HIV transmission during oral sex, an activity frequently performed by both male and female crack users during sexual exchanges for crack or money.

The combination of a strong compulsion to use and the power imbalance that occurs during an exchange of sex for drugs or money presents many challenges to prevention planners and program managers who develop and conduct HIV prevention programs for crack users. In particular, prevention programs need to be designed to reach women crack users who exchange sex for drugs.

Social Contexts That Increase HIV Risk

As discussed, specific behaviors place drug users at risk for HIV infection. However, these behaviors occur between people and often take place in differing settings and under differing social conditions. Drug use often takes place in small groups that meet in apartments, homes, or residential hotel rooms. Still others use drugs at "party houses," consisting of a variety of physical settings where individuals gather to use drugs. Examining the settings and social networks in which drug users interact and influence each other can help program planners and managers understand the social contexts that place drug users at high risk of HIV and can help them select and design more focused and effective HIV prevention interventions.

Injection drug use settings

Some drug-use social settings increase the potential for sharing contaminated equipment or for practicing unsafe sex, and thus influence the risk of HIV transmission. For example, one of the strongest predictors of HIV seroconversion among IDUs is injecting in outdoor settings or abandoned buildings (Friedman et al, 1995). In cities, the most recognized social settings where IDUs gather are "shooting galleries." Shooting galleries, also known as "safe houses" or "get-off houses," can be situated in back rooms, basements, dark hallways, or empty rooms of abandoned buildings in sections of cities where drug use rates are high (Inciardi et al., 1993).

Neighborhood heroin and/or cocaine dealers may operate shooting galleries as a service to customers-providing users, at the cost of just a few dollars, with a nearby location to safely "shoot-up." More often, however, gallery operators are drug users who provide a service for a small fee or a "taste" (sample) of someone else's drugs. For a fee, IDUs rent a set of works and relax while "getting off." After using the syringe and needle, the user generally returns them to a central storage place in the gallery where they are held until someone else rents them. These works also may be passed to another user in the gallery, which may involve an exchange of money, drugs, or sex (Inciardi et al., 1993).

For many IDUs, the use of shooting galleries is commonplace. For users who have no works of their own or their friends or "running partners" have no works, then galleries are their logical recourse. This is also true for those who purchase drugs far from home. In addition, some IDUs prefer local galleries because of the opportunities they provide to socialize with other users (Inciardi et al., 1993).

Crack houses

"Crack houses" are another drug use setting that poses a significant potential risk for HIV. Crack houses are places where users gather not only to purchase and smoke crack, but also to exchange sex for crack or for money to buy crack, or to provide money or drugs for sex (Inciardi et al., 1993). They may also be a place to manufacture or package crack. Crack houses can be located in private houses or apartments, abandoned cars, a vacant building, or a commercial establishment. Depending on the geographical region, crack houses are also known as "hit houses," "smoke houses," and "resorts."

As with shooting galleries, some crack houses charge users admission fees. For additional fees, crack houses may provide crack-smoking equipment, the crack itself as well as other drugs, rooms in which to have sex, and access to sex workers. Crack houses are more likely to be the scene of sex, stealing, bizarre behavior, begging and/or violence than are shooting galleries. Individuals who manage crack houses often recruit chronic crack users, particularly women, to whom they provide crack and sometimes food and shelter, in exchange for the women providing sexual services to male customers (Ratner, 1993).

Other settings

Shooting galleries and crack houses are not the only settings where risky sexual practices and drug use are linked. For instance, the availability of drugs at social and recreational settings, such as bars, massage parlors, social clubs, or through escort services also is frequently linked to risky sexual behavior.

No matter what drugs are used, however, the key component to social settings is the number of drug users in the setting. When social settings bring together multiple individuals who then either inject drugs in a way that transfers HIV-infected blood among them, or have high-risk sex, HIV transmission can more readily occur. Although popular culture dramatizes the risks of transmission in shooting galleries and crack houses, any gathering of people who use drugs, whether in an apartment or a street corner creates the risk of transmission.

Social networks

Social networks are characterized by groups of individuals who are linked by various relationships and common bonds. These networks may comprise people whose common link may be friendship, kinship, short-term acquaintances, or anonymous relationships. Social networks among drug users may vary, depending upon the type of drug used and how it is used, the size of the group, the degree in which the group is open to new members, the level of stability of the group, and the kind of social activity that occurs in the group (Needle et al., 1995).

Types of social networks. Networks generally have been characterized as "open" or "closed" systems (Trotter et al., 1995). In "closed networks," drug use takes place in private residences mainly among individuals who know one another. In these kinds of networks, it is uncommon for users to cross social, cultural, economic or geographic boundaries, thereby keeping HIV transmission relatively confined within the network. "Kinship networks" are one type of network where members have close kinship or family-based ties.

In "open networks," HIV may be more easily spread to a greater pool of individuals since the boundaries are not as tight as those in closed networks. Case Example 2.2 describes a type of open network, called an "acquaintance network," in which member turnover is frequent and multiple drug and sex exchanges occur on a regular basis.

Case Example 2.2

Social Networks: A Case Study

"Needle" is a young, HIV-positive, gay, white male. His apartment serves as the network's social center and as a 24-hour shooting gallery. Network members and those they "sponsor" can purchase and inject drugs at his apartment. Needle and other HIV-positive network members disclose their status, but they leave it up to each member to take preventive precautions. Although members have their own equipment, they still share it with others. When they gather at Needle's apartment, network members are interested in socializing and getting high and are not necessarily concerned with protecting themselves from HIV infection.

Source: Adapted from Elwood, 1995.

Social network webs. Large networks often are composed of smaller "webs" of individuals who may engage in risky drug use and sexual behavior (Trotter et al., 1995). Some of these webs are considered "HIV risk contact networks" whose members are at high risk of HIV infection because of the extent and nature of their connections with HIV-positive people in their own web or in connecting webs. If the personal networks of HIV-positive individuals are small and are not connected to larger webs where there are more interactions, the risk of HIV transmission may be less pronounced.

Familiarity with existing social networks within a community can help determine the most effective channels of communication among network members. For example, it may be useful to identify the key "gatekeepers" or "brokers" within a network, who act as the main link to the network's membership. Interventions designed to reach network gatekeepers can help alter risk behaviors within the network (Friedman, 1995).

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  1. "Shooting galleries" are defined and described in the section entitled "Social Contexts that Increase HIV Risk."
  2. Research on the history of drug injection in New York City has indicated that there has been a large-scale decline in the direct sharing of contaminated needles. This has been associated with the use of syringe exchange programs and with the fact that many users have switched to "snorting" heroin (Des Jarlais et al., 1994).
  3. The section on women in "Impact of HIV Among Special Groups of Drug Users," later in this PART, discusses this issue in further detail.

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