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Injection risk behavior among women syringe exchangers in San Francisco.
Lum, Paula J
The published version of this article is available at Substance Use and Misuse.
Lum, P., Sears, C., & Guydish, J. (2005). Injection risk behaviors among women syringe
exchangers in San Francisco. Substance Use and Misuse, 40,1681-1696.
Adult, California, Catchment Area (Health), Demography, Female, Homeless Persons, Humans,
Needle Sharing, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't,
Research Support, U.S. Gov't, P.H.S., Risk-Taking, Substance Abuse, Intravenous
Women who inject drugs in cities where syringe exchange programs (SEPs) are well established
may have different risks for HIV infection. In 1997, we interviewed 149 female syringe exchangers
in San Francisco, CA, a city with high rates of injection drug use that is home to one of the largest
and oldest SEPs in the United States. In this report, we describe their sociodemographics, health,
and risk behavior, and we examine factors associated with recent syringe sharing. Fifty percent
of respondents were women of color and the median age was 38 years. Most (86%) injected
heroin and nearly half were currently homeless or had recently been incarcerated. One-third of
all women reported needle sharing in the prior month. This was higher than the rate of needle
sharing reported by a mixed gender sample of San Francisco exchangers in 1993, although it
resembled the rate reported by a mixed gender sample in 1992. In a multivariate analysis, syringe
sharing was associated with age, housing status, and sexual partnerships. Syringe sharers were
more likely to be young, homeless, or have a sexual partner who was also an injection drug user.
While wide access to sterile syringes is an important strategy to reduce HIV transmission among
injection drug users (IDU), syringe exchange alone cannot eradicate risky injection by female IDU.
Additional efforts to reduce risky injection practices should focus on younger and homeless female
IDU, as well as address selective risk taking between sexual partners.
Citation: Lum, P., Sears, C., & Guydish, J. (2005). Injection risk behaviors among women
syringe exchangers in San Francisco. Substance Use and Misuse, 40,1681-1696.
Injection Risk Behavior Among Women Syringe Exchangers in San Francisco
Paula J. Lum, MD MPH1, Clare Sears, MA2,Joseph Guydish, PhD2.
1. The Positive Health Program, Department of Medicine, University of California, San
Francisco and San Francisco General Hospital
2. The Institute for Health Policy Studies, Department of Medicine, University of California, San
Keywords: AIDS, HIV, Syringe Exchange, Injection Drug Use, Women
ACKNOWLEDGEMENTS: This research was conducted with the support of grants from the
San Francisco AIDS Foundation, the National Institute of Mental Health (T32 MH-19105-10),
the California-Arizona node of the NIDA Clinical Trials Network (U10 DA-105815), and the
NIDA San Francisco Treatment Research Center (P50 DA-09253). We thank the San Francisco
AIDS Foundation’ s HIV Prevention Project. Dedicated to the memory of Roslyn Allen
Corresponding author: Joseph Guydish, PhD, Institute for Health Policy Studies, 3333 California
St., Suite 265, San Francisco, San Francisco, CA 94118; tel (415) 476-0954; fax (415) 476-0705;
Women who inject drugs in cities where syringe exchange programs (SEPs) are well established
may have different risks for HIV infection. In 1997, we interviewed 149 female syringe
exchangers in San Francisco, CA, a city with high rates of injection drug use that is home to one
of largest and oldest SEPs in the United States. In this report, we describe their
sociodemographics, health, and risk behavior, and we examine factors associated with recent
syringe sharing. Fifty percent of respondents were women of color and the median age was 38
years. Most (86%) injected heroin and nearly half were currently homeless or had recently been
incarcerated. One-third of all women reported needle sharing in the prior month. This was higher
than the rate of needle sharing reported by a mixed gender sample of San Francisco exchangers
in 1993, although it resembled the rate reported by a mixed gender sample in 1992. In a
multivariate analysis, syringe sharing was associated with age, housing status, and sexual
partnerships. Syringe sharers were more likely to be young, homeless, or have a sexual partner
who was also an injection drug user. While wide access to sterile syringes is an important
strategy to reduce HIV transmission among injection drug users (IDU), syringe exchange alone
cannot eradicate risky injection by female IDU. Additional efforts to reduce risky injection
practices should focus on younger and homeless female IDU, as well as address selective risk
taking between sexual partners.
Injecting drug use is a major route of transmission for HIV in the United States (Centers for
Disease Control and Prevention, 2002; Centers for Disease Control and Prevention, 2003), and
women who inject drugs are at significant risk of infection (Davis et al., 1998; Freeman et al.,
1994; Hader et al., 2001; Prevots et al., 1996). Of the more than 150,000 AIDS cases reported
among women nationwide, through December 2002, injecting drug use accounted directly for
39% of cases (Centers for Disease Control and Prevention, 2003). Early research among
predominantly male injection drug users (IDU) documented risk factors for HIV infection,
including frequency of injection, number of injections shared or needle sharing, early age of
initiation, cocaine injection, and shooting gallery attendance (Chaisson et al., 1989; Chitwood et
al., 1995; Friedland et al., 1985; Moss et al., 1994; Schoenbaum et al., 1989; Vlahov et al.,
1990). Later studies, however, suggested that female and male IDU engaged in injection risk
behavior differently (Bennett et al., 2000; Dwyer et al., 1994; Gollub et al., 1998; Miller and
Neaigus, 2001) and that risk factors for HIV infection among IDU differed between the sexes
(Bruneau et al., 2001; Kral et al., 1997; Strathdee et al., 2001; van Ameijden et al., 1999). Studies
reporting exclusively on HIV transmission in female IDU detected additional risk among women
of color (Magura et al., 1993; Watters et al., 1994), women who engaged in prostitution
(Astemborski et al., 1994; Watters et al., 1994), who were out of drug treatment (Bruneau et al.,
2001), and who had a history of sexually transmitted disease (Strathdee et al., 2001; Watters et
al., 1994). However, far less is known about the determinants of HIV-related risk behavior
among female injectors since the establishment in the U.S. of syringe exchange programs (SEPs).
SEPs are one public health strategy to prevent the transmission of HIV for persons who reuse
contaminated syringes for drug injection (Centers for Disease Control and Prevention, 2001). In
contrast with most other industrialized nations, there has been substantial political opposition to
SEPs in the U.S., including a federal funding ban that prohibits using government monies to
support these programs and State paraphernalia laws that hamper operation by criminalizing
syringe possession or distribution (Jaffe, 2004; Lurie, 1995; Vlahov et al., 2001). Operating in a
tenuous legal and political climate, SEPs have nonetheless received the support of volunteers,
community based organizations and some local governments and, since their establishment in the
U.S. in 1982, they have served increasing numbers of IDU (Bluthenthal et al., 1998; Des Jarlais
et al., 2000). San Francisco’ s SEP was launched in 1988 by a group of volunteers, and it is now
one of largest and oldest in the U.S., operating legally since 1993, when the local government
declared a public health emergency.
Many cities with SEPs have reported decreases in HIV incidence in IDU (Des Jarlais et al.,
2000; Gibson et al., 2001). In San Francisco, HIV incidence among IDU declined from 3.9 per
100 person years of observation (PYO) to 1.2 per 100 PYO by 1990 (Moss et al., 1994).
However, no reductions in HIV prevalence among IDU in San Francisco (range 8-10%) have
been documented in the last ten years (Kral et al., 2001; Watters, 1994). Reports of continued
syringe sharing by SEP clients are not uncommon (Paone et al., 1997; Valenciano et al., 2001;
Wood et al., 2002). Most studies of SEP clients report on predominantly male populations,
although one study of female exchangers reported elevated injection risk behaviors among sex
workers (Paone et al., 1999). A better understanding of factors associated with syringe sharing
among female SEP users can inform interventions to reduce further the transmission of HIV and
other blood borne pathogens among female IDU.
In July 1995, the San Francisco AIDS Foundation’ s HIV Prevention Project (SFAF-HPP)
launched an indoor women-only SEP site and, in 1997, SFAF-HPP contacted the authors to
request a program evaluation to assess and improve SEP services for female IDU. We
subsequently interviewed a sample of female IDU recruited from the women-only and mixed-
gender SEP sites in San Francisco. Although participants did not experience direct benefits from
the study, we presented our findings to SFAF-HPP who used the data to inform planning
decisions and enhance program-level services for female IDU. In this paper, we report on our
data from the women-only and mixed-gender SEP sites. First, we describe the sociodemographic,
health, and risk behavior characteristics of female syringe exchangers in San Francisco. Second,
we examine factors associated with risky injection behavior in settings where SEPs are well
We recruited a stratified sample of female syringe exchangers for anonymous, cross-sectional
interviews from all twelve sites of the SFAF-HPP in operation at the time of the study. For the
purposes of the program evaluation, one-third of the study sample was recruited from street-
based SEPs, one-third from a storefront SEP, and one-third from an indoor SEP open to women.
The street-based SEPs were located in eight different neighborhoods throughout the city and each
operated for a two-hour period, one day per week. The storefront SEP was located in the South of
Market district and operated on three different weekdays, for two-hours per day. The women-
only SEP operated from an indoor location in the Mission district and was open for a two-hour
period, one day per week. All of these SEPs offered syringe exchange, ancillary injection
supplies (cotton, cookers, water, and bleach), condoms and referrals; the storefront and women-
only SEPs also offered on-site medical care.
Study participants were recruited at the SEP sites by a member of the interview team. This
team consisted of eight women, diverse in age and ethnicity, all of whom had prior outreach or
interview experience with female drug users. After a potential study participant had completed
her syringe exchange transaction, an interviewer approached the woman to describe the study and
invite her to participate, explaining that participation was voluntary and not a condition of using
SEP services. If the woman was interested in participating, the interviewer then screened for
study eligibility. Eligibility criteria were self-reported age greater than 17 years, history of drug
injection during the preceding 30 days, and syringe exchange at that site on the day of
recruitment. A female IDU accompanying a male syringe exchanger was considered eligible if
syringes he exchanged were also for her own use, and five women entered the sample under this
eligibility criterion. A total of 190 women were recruited and 163 (86%) agreed to participate.
Most who declined cited lack of time, and they did not differ significantly from those who agreed
to participate by observed ethnicity or recruitment venue. Two women chose to terminate the
interview before completion and these interviews were subsequently excluded from analysis. An
additional 12 interviews were excluded because of eligibility criteria or because they were
repeated interviews, leaving a total sample size of 149. All interviews were conducted between
May and September 1997.
After providing informed consent, participants accompanied the interviewer to a nearby quiet
café or fast food restaurant to complete a 30-40 minute face-to-face survey. Data collection
occurred during hours of SEP operations, so that the study sample was representative of persons
attending SEPs. After completion, participants were offered $20 compensation for time spent in
the study, as well as referrals to medical care, drug and alcohol treatment, emergency housing,
and other social services. All study procedures were approved by the Committee on Human
Research at the University of California, San Francisco.
The survey collected information on participants’ demographics, health status, drug use, SEP
utilization patterns, syringe sources, and sexual behavior. Questions were based on variables used
in prior studies of SEP participants in San Francisco (Guydish et al., 1998; Guydish et al., 1995)
with additional variables of interest submitted by an all-female community advisory board. The
survey was pre-tested with 5 female IDU using the study procedures described above.
Sociodemographic variables included age, race, education, housing, residence with other
IDUs (“ do you live with anyone else who injects drugs” ), and incarceration. Health variables
included self-reported health status (“ how do you rate your health?” ), insurance status, health
care utilization, HIV testing and infection status, and lifetime prevalence of selected medical
conditions. We also collected data on recent (12-month) history of physical and sexual assault.
Drug use variables included the frequency and types of injected and non-injected drugs, drug
treatment, and injecting partners and practices. Syringe sharing was defined as the borrowing or
lending of a used syringe in the prior 30 days. Other injection-related risk behavior in the past 30
days included the number of syringe-sharing occasions, number of sharing partners, order of
sharing, bleaching when sharing, and sharing ancillary injection equipment, such as cookers,
cottons, and rinse water.
SEP-specific variables included the duration of SEP exposure, categorized as new (less than
one year), moderate (1-5 years), and long-term (> 5 years), and the frequency of SEP attendance
in the prior month (dichotomized as weekly or more vs. less than weekly), as well as time spent
and services received there. Syringe source variables included self-reported number of syringes
owned (“ how many needles do you own right now?” ) dichotomized as more than twenty vs.
twenty or less, percent of syringes obtained from exchange dichotomized as 100% (SEP sole
source of syringes) vs. <100% (sources of syringes other than SEPs), number of times use each
syringe, dichotomized as 1 (single use) vs. > 1 (syringe re-use), and perceived access to new
syringes (“ can you get enough needles to use each needle one time only?” Yes/No).
Sexual behavior variables included the number, gender, and type of sex partners (main,
casual, and sex-trade) in the last thirty days, as well as types of sex (vaginal, anal and oral sex)
practiced in the last thirty days. We operationally defined “ sex trade” as transactions in which
vaginal, anal, or oral sex was traded for drugs, money, or a place to stay. Percent condom use in
the preceding 30 days for oral, vaginal, and anal sex were assessed for sex with male partners.
Higher risk sexual behavior was defined as less than 100% condom use AND more than one
sexual partner in the prior 30 days.
Survey data were analyzed to describe the characteristics of female IDU attending SEPs and
to examine factors associated with syringe sharing. Summary statistics included frequency tables
for categorical variables and medians and interquartile ranges (IQRs) for continuous variables.
Continuous variables were categorized for frequency tables using logical cutoffs. Bivariate
associations between predictor variables and outcome variables were analyzed using the Chi-
Square test of association or Fisher’ s Exact test for small cell sizes. The Mantel-Haenszel Chi-
Square was used to test ordinal bivariate associations. We examined the independent effects of
the predictor variables on recent needle sharing using multivariate logistic regression (Hosmer
and Lemeshow, 1989). Variables selected for inclusion in multivariate models were those found
to have a Chi-Square p-value < 0.05 on bivariate analyses or considered potential confounders
based on expected biologic and behavioral inference. Multivariate models were evaluated using
logistic regression methods. The final model was constructed with significant predictors entered
simultaneously. Adjusted odds ratios (ORs) and 95% confidence intervals are reported for the
model. All statistical analyses were performed using the Statistical Analysis System (SAS)
version 6.12 statistical package for IBM-PC.
Baseline Characteristics of Female Syringe Exchangers
Sociodemographics and health status. Among the 149 participants enrolled, the median age
was 38 years (IQR = 28-45) and 50% were women of color (26% African American, 12% Latina,
and 13% another non-white ethnicity, including 3% Native American, 1% Asian, 1% Pacific
Islander, and 8% “ Other Race” ; Table 1). Most had a high school education and lived currently
with another IDU. Nearly half were currently homeless, and as many had been incarcerated
during the last two years. Most of the 63 homeless respondents reported currently staying in hotel
rooms (37%), on the streets (33%) or with a friend (21%); a small proportion stayed with family
(5%) or in a shelter (3%). Few (15%) participants reported full or part-time employment, while
63% reported illegal income sources. The most commonly reported income-generating strategies
were under-the-table jobs (48%), drug sales (42%), prostitution (36%), and panhandling (35%).
Most respondents (83%) had previously been pregnant, although fewer (59%) reported having
children of any age. Thirty seven percent had children under 18 years old, but of these 55 women,
only 15 (27%) currently lived with their children. One third (33%) of women reported a physical
assault and 11% percent reported a sexual assault in the prior year.
When asked to rate their health, few women (5%) reported excellent health status, and more
than half (54%) reported either fair or poor health (data not shown). Two-thirds had no health
insurance, yet nearly all sought health care in the prior year, primarily from free clinics (68%)
and emergency departments (63%), but also from SEPs offering medical care (33%). Nearly all
(96%) women had been previously tested for HIV and most had received an HIV test within the
last 12 months (Table 1). The median number of prior HIV tests was six (IQR=3-10). Nine
women (6%) reported they were HIV-positive, half of whom had been diagnosed in the
preceding year. Few respondents knew about hepatitis C virus (HCV), and only 22% reported
known HCV infections. The most common prior health conditions were pregnancy (83%),
injection-related skin and soft tissue infections (70%), drug overdose (59%), and sexually
transmitted infections (STIs) (55%).
Drug use behavior. The median age of first injection was 20 years (IQR = 17-25), and 42%
reported a family member injecting drugs while they were growing up. Many (73%) reported a
history of drug treatment and methadone detox (47%), methadone maintenance (36%) and
outpatient (34%) were the most commonly accessed modalities. Almost two-thirds (64%) had
entered treatment voluntarily at least once, although 22% reported at least one treatment episode
mandated by the criminal justice system. Few (14%) were in treatment at the time of interview
and 54% reported interest in entering treatment if a slot were available. Most women were
frequent heroin injectors (Table 2). Most (62%) reported a main injecting partner, someone with
whom they usually purchased, prepared, and injected their drugs. Several (36%) reported more
than one injecting partner in the prior month.
Table 1. Selected sociodemographic and health characteristics, N=149
Variable N (%) Syringe sharing N (%)p-value
All 149 (100)52 (35) --
Age (median 38 years, IQR=28-45)
>=30 108 (72) 29 (27).001
18-29 41 (28)23 (56)ns
White 74 (50)32 (43) .034
Non-white 75 (50)
20 (27) ns
>= High School 99 (67) 31 (31)ns
< High School 50 (33) 21 (42) ns
Lives with IDU 98 (66) 43 (44).001
Homeless 63 (43) 32 (51) .0003
Recent incarceration 65 (44) 31 (48).003
HIV test in prior year (n=141) 101 (72) 30 (30).045
Selected lifetime health conditions
HIV/AIDS 9 (6)2(1) ns
Hepatitis C virus 31 (22) 13 (42)ns
Pregnancy 124 (83) 39 (31).049
Skin or soft tissue infection 105 (70)33 (31)ns
Drug overdose 88 (59) 34 (39) ns
Sexually transmitted infection 81 (55)35 (43) .024
Physical assault in last year 49 (33)22 (45)ns
Sexual assault in last year
Illegal Source of Income
Family history of IDU
Fifty-two participants (35%) reported sharing a syringe in the preceding 30 days (Table 2). Of
these, few (24%) consistently bleached their syringes between uses, and the majority (71%) used
the syringe after their syringe-sharing partner (data not shown). Twenty-seven women (18%)
reported sharing syringes on more than five occasions in the preceding 30 days, and 14 (9%)
reported more than one syringe-sharing partner. Many participants reported inconsistent
cleansing of the injection site and ancillary equipment sharing in the prior 30 days, and this was
highly correlated with recent syringe sharing (Table 2).
SEP utilization and syringe sources. Most women (83%) had been attending SEPs for more
than one year, and many attended at least weekly (Table 2). They arrived primarily on foot
(72%), followed by public transportation (16%) (data not shown). Respondents from the women-
only SEP spent significantly more time there than respondents from SEP sites that served men
and women together (40 vs. 10 minutes; p=0.0001). On the day of recruitment, respondents
exchanged an average of 33 needles (range=1-400). Most exchanged for themselves, but half
(54%) also exchanged syringes for others. Respondents also reported obtaining other services at
SEPs, including other safer injection supplies, i.e., cotton, alcohol wipes, bleach (91%), condoms
(81%), emotional support (68%), food (38%), health care (33%), and clothing (23%).
SEPs were the sole source of new syringes for most participants, and the median number of
syringes currently in possession was twenty (Table 2). During the 16-week study period, women
exchanged 172,000 syringes at SFAF-HPP sites (personal communication, SFAF-HPP). Half the
women (53%) felt they had access to enough syringes to use a brand new needle for each
injection, but few (33%) reported one-time use. Most women (67%) re-used their own syringes
and deployed each an average of three times before it was discarded or exchanged.
Table 2. Selected drug use behavior in last 30 days and SEP utilization, N=149
Variable N (%) Syringe sharing N (%)
All 149 (100) 52 (35)
Frequency of injection
Less than daily (0-30) 54 (36) 14 (26) ns
Daily or more (>30) 95 (64) 38 (40).083
Heroin 128 (86) 44 (34) ns
Amphetamine 51 (34) 24 (47)
Cocaine 28 (19) 11 (39)ns
Main injecting partner 92 (62) 38 (41).037
Number of injecting partners, n=148
0-1 94 (64) 24 (26)ns
>1 54 (36) 28 (52) .026
Shared cooker, cotton, or rinse water 91 (61) 44 (48) .001
Cleaned skin before injection
Always 57 (38) 10 (18) ns
Not always 92 (62) 42 (46).0005
SEP exposure, n=144
Long-term (>5 years) 49 (34)16 (33) ns
Moderate (1-5 years) 71 (49)27 (38)ns
New (< 1 year) 24 (17)7 (29) ns
SEP attendance > weekly, n=146 103 (71)31 (30) ns
Syringes only from SEP, n=148 130 (88)41 (32) .014
Number of syringes owned
>20 71 (48)18 (25) ns
=<20 76 (52) 33 (43).021
Syringe re-use 100 (67) 47 (47) .001
Sexual behavior. Sixty percent of the women identified as heterosexual, 20% bisexual, and
9% lesbian; 73% reported steady sex partners, 51% reported IDU sex partners, and 31% reported
sex trade partners (Table 3). Ninety-nine (67%) participants reported vaginal, anal, or oral sex
with a man in the prior month. While only 30% of respondents reported consistent condom use,
women with sex trade partners were more likely to report consistent condom use than women
with non-paying partners (67% vs. 11%; p=0.001). Seventeen percent of all respondents reported
less than 100% condom use AND more than one sexual partner in the prior 30 days.
Correlates of Syringe Sharing. On bivariate analysis, sociodemographic variables associated
with recent syringe sharing were age under 30 years, white race, living with another IDU, current
homelessness, incarceration, recent sexual assault, having any children and having a family
history of IDU (Table 1). Education, employment, and illegal source of income were not
significantly associated with recent needle sharing. Health variables associated with recent
syringe sharing were history of an STI and an HIV test within the preceding year. A prior
pregnancy was inversely associated with syringe sharing. Drug use variables associated with
recent syringe sharing included injection of amphetamine, a main injecting partner, number of
injecting partners, sharing ancillary injection equipment, and inconsistent skin cleansing prior to
drug injection (Table 2). Recent syringe sharing also was associated with obtaining new syringes
from sources other than SEPs, possessing fewer syringes, and re-use of one’ s own syringes
(Table 2). There was no association between recent syringe sharing and SEP exposure or
frequency of SEP attendance. Sexual variables associated with recent syringe sharing included
having an IDU sex partner in the prior thirty days (Table 3). In a multivariate logistic regression
model, recent syringe sharing was associated with younger age, current homelessness, and an
IDU sex partner (Table 4).
Table 3. Selected sexual behavior in prior 30 days, N=149
Variable N (%) Syringe sharing N (%)p-value
All 149 (100) 51 (34)
Steady sex partner 109 (73) 37 (34)ns
Casual sex partner 57 (38)22 (39) ns
Sex trade partner 46 (31)
16 (35) ns
IDU sex partner (n=144) 74 (51) 38 (51) 0.001
Anal, vaginal, or oral sex with male 99 (67)41 (41)ns
Higher risk sex*
Yes 26 (17)11 (42) ns
No 123 (83) 82 (67) ns
*Higher risk sex = less than 100% condom use AND > 1 sexual partner in the prior 30 days.
Table 4. Logistic regression model of syringe sharing in prior 30 days.
Variable Adjusted odds ratio 95% Confidence Interval
Younger Age 3.5 1.52-8.21
Current Homelessness 3.8 1.71-8.44
IDU Sex Partner 4.01 1.77-9.04
In this study, female IDU in San Francisco were shown to have precarious dual risk for HIV
infection, not only via contaminated injection equipment but also through sexual contact with
IDU or other high-risk partners. Despite regular and frequent SEP use, one-third (35%) reported
sharing a used syringe for drug injection in the prior month. This was higher than the rate of
needle sharing (21%) reported by a mixed gender sample of San Francisco exchangers in 1993
(Sears et al., 2001), although it resembled the rate (36%) reported by a mixed gender sample in
1992 (Guydish et al., 1998). In our study, female syringe sharers were more likely to be young,
homeless, and have a sexual partner who was also an IDU.
Previous research has identified young IDU as at high risk for HIV infection (Bailey et al.,
2003; Guydish et al., 2000; Hahn et al., 2002). Younger age has been consistently associated with
higher rates of injection risk behavior and blood-borne infection (Battjes et al., 1992; Fennema et
al., 1997; Fuller et al., 2004; Garfein et al., 1996; van Ameijden et al., 1993) and one study found
that young women IDU in San Francisco engaged in injection-related risk behaviors at higher
rates than young men IDU (Evans et al., 2003). Our results suggest that the association of
younger age and HIV risk persists among women who use syringe exchange programs. Young
IDU are typically homeless runaways, who are often involved in the underground street
economy. They make their living through prostitution, drug sales, theft, panhandling,
pornography, or selling stolen property (Office of National Drug Control Policy, 2001). They
often experienced a large number of negative events prior to leaving home and are more likely to
have experienced traumatic life events, such as intergenerational drug abuse, forced
institutionalization, and survival sex (Martinez et al., 1998).
We found that the life experiences of female syringe exchangers in San Francisco commonly
include intergenerational drug use, homelessness, pregnancy, and incarceration. Homelessness
has been associated with HIV infection among IDU in other North American cities (Strathdee et
al., 1997), and we found an association between homelessness and continued syringe sharing in
our study. State paraphernalia laws that criminalize the possession of syringes for illicit drug use
may contribute to this risk factor by discouraging IDU to carry their own sterile syringes and
homeless IDU may make practical choices to borrow syringes so as to avoid arrest for syringe
Our finding that recent syringe sharing occurs more often among female syringe exchangers,
who report sex with another IDU, highlights the complexity of dual risk for women who use
drugs and the challenge this poses to HIV prevention programs. Previous research supports our
finding that women’ s syringe sharing behavior is frequently embedded in sexual relations (Booth,
1995; Davies et al., 1996; Dwyer et al., 1994; Freeman et al., 1994; Gollub et al., 1998; Latkin et
al., 1998; MacRae and Aalto, 2000; Sherman et al., 2001; Tortu et al., 2003). As women have
historically assumed positions of deference and care-giving in both drug-using networks and the
larger society, it is unsurprising that most female syringe sharers in our study reported injecting
after their drug-using partners with the same needle. In contrast to a study of female SEP clients
in five U.S. cities (Paone et al., 1999), we found that participants engaging in sex work did not
report greater injection risk than non-sex workers. Participants in Paone’ s study were more likely
to be African-American, Latina, currently in drug treatment, and currently housed than
participants in this study, and these differences may contribute to the different relationship
between sex work and injection risk reported here.
There are several limitations to our analyses. First, our small sample size may have limited
our power to detect small but potentially important differences between study groups. Second,
while some studies have shown that self-reported data by IDU are valid, others have suggested
that IDU underreport risk behavior, particularly those related to illegal activities (Des Jarlais et
al., 1999; McCusker et al., 1992). Our use of trained female interviewers with extensive prior
experience working with female drug users may have mitigated this bias. In addition, our
sample’ s self-reported HIV prevalence of 6% is consistent with previously estimated rates for
women drug users in San Francisco (SF-HPPC, 1996) and on the West Coast (Prevots et al.,
1996), supporting the validity of this self-reported data. Third, this study focused on one subset
of female IDUs – female syringe exchangers – and additional research is needed to investigate
the risk behaviors of female IDU who do not use SEP. Fourth, our analysis relied upon linear
models which, although standard in the field, have recently been criticized as inappropriate for
understanding the complex, multi-dimensional, and non-linear processes of substance abuse
(Buscema, 1998; Buscema, 2002). Finally, the data presented in this study were collected in 1997
and may not reflect the risk behaviors of women exchangers in San Francisco today. In
particular, the women’ s needle exchange site described here closed in 2002, following budget
cuts and decreased site utilization, possibly driven by major gentrification and the relocation of
IDUs to other neighborhoods. The ancillary services that were provided at the women’ s sites
(free medical care, HIV testing, free food and outreach workers) are now provided at most San
Francisco SEP sites. Despite these changing circumstances, this study contributes important data
to the limited number of published studies of HIV-risk among female IDU who use SEPs.
While wide access to sterile syringes is an important strategy to reduce HIV transmission
among IDU, syringe exchange alone cannot eradicate risky injection by female IDU. Many
female SEP clients engage in selective risk taking, i.e., choosing to share syringes with sexual
partners with whom they have steady relationships and with whom they also do not use condoms
(Valente and Vlahov, 2001). Interventions that address injection risk behavior between sex
partners, as well as the potential influence of traditional gender roles, violence, and drug use
needs on the dynamics of these relationships, are needed for young and novice female IDU.
These interventions might focus on negotiation and communication skills that promote sterile
syringe use, as well as condom use, in a setting that promotes rather than challenges trust and
intimacy. Syringe sharing in the era of needle exchange also appears to occur among those most
vulnerable to infection, i.e., the young and homeless. On a structural level, interventions that
address the greater health risks associated with new-onset injection and homelessness are also
urgently needed. Programs that increase access to clean syringes may operate not only to reduce
risk of infectious disease, but also as an avenue to drug treatment and other health and social
services. For SEPs to succeed as a bridge to treatment, treatment systems may also require
change to increase access and availability of services, and to reduce stigma associated with
injection drug use. Policy initiatives mandating treatment as an alternative to incarceration for
drug-involved offenders, like those currently operating in Arizona and California (Administrative
Office of the Courts, 1999; Speiglman, Klein, Miller, & Noble, 2003), offer one example of this
type of system change.
Despite a host of competing concerns for active female injectors, SEPs in San Francisco
have evolved into points of regular contact with most women visiting on a weekly basis. Few
other HIV prevention programs report such regular voluntary attendance. SEPs, and female-
focused SEPs in particular, may offer an ideal community platform to apply new intervention
strategies toward women drug users at continued risk.
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