BACKGROUND
In the United States, the proportion of diagnosed HIV infections attributable to injection drug use declined from an estimated 8.9% in 2009 to 6.0% in 2014.1,2 3–5 6–8
SSPs facilitate safe disposal of used syringes and provide free sterile syringes and risk reduction education to PWID, and can provide or refer clients to other harm reduction interventions, medical and mental health care, and social services. By reducing injection-related risk behaviors, SSPs subsequently reduce transmission of infectious diseases such as HIV and hepatitis C virus (HCV) among SSP clients, as well as the broader community.9 10,11 12,13 14 15
In late 2014, Scott County in southeastern Indiana experienced the largest HIV outbreak among PWID in a nonurban setting in the United States. Between November 18, 2014, and November 1, 2015, 181 persons received a diagnosis of HIV in a small rural county (population 24,000), where only 5 HIV infections had been diagnosed from 2004 through 2013.16 16 17
The Scott County SSP was established on April 4, 2015, within 1 week of the Indiana Governor declaring a public health emergency.17 18
We used routinely collected program data from the Scott County SSP and data from a qualitative study in the nonurban community in which the SSP was established in response to an HIV outbreak, to compare injection-related risk behaviors and perceptions of risk before and after the emergency implementation of the SSP. These findings could inform HIV prevention efforts in other jurisdictions that are preparing or expanding SSPs as part of a comprehensive approach to addressing injection-related harms.
METHODS
A mixed methods design, using quantitative program data and qualitative study data collected in Scott County, was used to understand changes in risk behaviors and risk perceptions among PWID.
Quantitative Program Data Measures and Analysis
Routinely collected data from the Scott County SSP database were available for all clients from the date the SSP was established, April 4, 2015, to August 30, 2015. To enable comparison across multiple visits to the SSP, data for this analysis were limited to clients with at least 2 visits, at least 7 days apart. At each SSP visit, staff used a standard form to collect data on self-reported current injection-related risk behaviors, number of sterile syringes dispensed, and estimated number of syringes returned for safe disposal. Behavioral measures included number of times the same needle was used for injection and syringe sharing to inject or divide drugs, or sharing other injection equipment. The maximum reported number of injections per day was assessed by SSP staff as a proxy for syringe need; this measure was used by SSP staff to calculate the number of sterile syringes dispensed to each client. A unique identifier was assigned to each SSP client to track program data over time without collecting personal identifying information (eg, names). We identified the first and most recent visit for each client and summarized injection-related risk behaviors, and counts of syringes provided and returned, at these 2 time points.
We tested for statistical differences for categorical and continuous variables, accounting for within-person correlation, using the McNemar χ2 and Wilcoxon signed-rank tests, respectively. Statistical analyses were conducted using SAS 9.3 (SAS Institute, Cary, NC). Analysis of SSP program data was approved by the Centers for Disease Control and Prevention (CDC) through a determination in accordance with federal human subjects protection regulations and CDC policies and procedures that did not require review by an institutional review board.19,20
Qualitative Study Data Measures and Analysis
Qualitative data were collected during a research study conducted from July to September 2015 to identify factors that may have facilitated rapid HIV transmission in Scott County. Purposeful sampling was conducted in the community served by the SSP through multiple methods to ensure a wide cross-section of the PWID population and included service provider referrals, peer referrals, and street recruitment. Persons were eligible to participate if they resided in Scott County, were ages 18 years and older, reported injection drug use in the previous 12 months and provided informed consent. Past-year injection drug use was assessed by observing recent physical marks of injection and confirmed during the in-depth interviews that described injection practices. The interviews were anonymous; no names or other identifying information were collected.
Initially, 4 focus groups (FGs) were conducted to assess community perceptions around injection practices and evaluate SSP access and utility. Preliminary findings from FGs informed final revisions to the interview guide for private interviews (PIs). PIs were conducted approximately 1 month later to assess individual-level behaviors, including SSP use, and to explore emerging topics raised in FGs. In total, 6 participants interviewed in FGs also participated in PIs.
Study staff used semistructured interview guides to conduct FGs and PIs. Relevant FG questioning included, “How have people's drug injection practices changed, if at all, since you became aware of HIV in the community? What are they doing differently? What's the same?” A short anonymous demographic survey was administered after the FGs to collect information on age, race/ethnicity, and other background characteristics. Relevant PI questions assessed the last time the participants injected and how that differed from injection practices before knowledge of HIV in the community. Specific probes further assessed injection frequency, syringe disposal practices, and syringe and other injection equipment sharing practices. Demographic and background information to characterize the PI sample were collected through the eligibility screener and during interviews.
FGs and PIs were digitally recorded, transcribed, cross-checked, and prepared for descriptive analyses using NVivo 10 software. To enhance rigor, 2 researchers analyzed data by independently reviewing transcripts and then comparing notes for intercoder agreement before coding data. Transcripts were coded into broad categories and then subcoded into refined categories. Results captured descriptions of changes in injection risk behaviors over time after the HIV outbreak and SSP. We present participant direct quotes denoted by a unique anonymous code that indicates the type of interview (FG or PI) and a unique, sequential number (eg, PI12).
Human subjects and ethics review and approval were received for the qualitative study from institutional review boards at CDC and Indiana University.
RESULTS
SSP Client and Qualitative Study Participant Characteristics
The SSP enrolled 237 clients between April 4, 2015, and August 30, 2015; 148 (62%) had documentation of at least 2 visits that were at least 7 days apart and were included in our analysis (Table 1 ). These 148 clients had a total of 854 visits (median: 4; range: 2–27) and total of 1479 weeks (median 10; range: 1–23) between the first and most recent visit. This corresponds to an overall rate of 0.58 visit per person-week across clients (854 visits per 1479 person-weeks). The median age of clients was 34 years (range: 18–63 years), 56% were male, and 98% were non-Hispanic white. The majority (89%) of SSP clients at their first visit reported injecting OPANA ER with INTAC, a proprietary formulation of extended-release oxymorphone with non-FDA approved abuse deterrent formulation (hereinafter Opana) (Table 1 ). Most (84%) SSP clients reported having been tested for HIV at their first visit; data on HIV/HCV status were not systematically collected.
TABLE 1.: Selected Demographic and Background Characteristics Among PWID, Indiana, April 4, 2015–September 30, 2015
A total of 56 qualitative study participants (31 from FGs and 25 from PIs) were included in the qualitative data analysis (Table 1 ). These participants had a similar distribution of race, sex, and age to SSP clients included in the analysis; with the exception of FG participants, who were more commonly female (52% versus 44%). Most PI participants (92%) and FG participants (97%) reported primarily injecting Opana within the previous 12 months. All PI participants and 97% of FG participants reported being tested for HIV. Compared with PI participants, a larger percentage of FG participants reported HCV infection (93% versus 84%) and HIV infection (59% versus 40%). Most qualitative study participants were enrolled in the SSP (76% of PI and 90% of FG participants).
Sharing of Syringes and Other Injection Equipment
At first SSP visit, 18% of clients reported sharing syringes to inject, 19% reported sharing syringes to divide drugs, and 24% reported sharing other injection equipment, such as cookers, filters, and water. At most recent visit, all 3 sharing practices had decreased significantly, but still were reported by some SSP clients (Table 2 ).
TABLE 2.: Differences in Self-reported Injection Risk Behaviors and Syringe Services Provided Between First and Most Recent Visit Among Clients Enrolled in the Scott County SSP, Indiana, April 4, 2015–August 30, 2015 (n = 148)
We'd put water in a cup, and everybody would use the same water and can… my boyfriend, friends, family, cousins, sister. If I was sick, had a pill, and I didn't have a needle, I would use whoever's was there…There's (also) been a couple times I've bought used needles and, used bleach to rinse them out…I've used needles before that the plungers were broke, and we'd melt them back together to use…I'm sure the person I was sharing with probably shared with everybody too (PI06).
All qualitative study participants reported high-risk sharing practices of syringes and other injection equipment before their awareness of the HIV outbreak and presence of the SSP, whether in reference to themselves and/or others (Table 3A ). Participants explained that sharing was widespread because of extremely limited access to new syringes, limited knowledge that sharing other injection equipment (independent of the syringe) was a risk factor for HIV/HCV, and willingness to inject with a discarded syringe when no other syringe was available.
TABLE 3.: Sample Quotes: Injection-Sharing Behaviors Before and After Implementation of the Scott Country SSP, Indiana, April 4, 2015–August 30, 2015
TABLE 3-A.: Sample Quotes: Injection-Sharing Behaviors Before and After Implementation of the Scott Country SSP, Indiana, April 4, 2015–August 30, 2015
Participants also reported sharing syringes and other injection equipment when an Opana pill was shared with others. Practices included sharing previously used syringes to divide drugs (backloading); sharing syringes to inject; and sharing cookers, water, and filters. When backloading, 1 person uses 1 syringe to draw up drug solution from a shared cooker and then squirts the drug into the back of other people's syringes. When sharing syringes to inject, 1 person injects with a syringe and passes it to other people to inject. When sharing other injection equipment, multiple people insert their syringes into a shared cooker to draw up drug solution and inject. Five participants reported never sharing syringes to inject or divide drugs before the SSP; 2 were insulin-dependent diabetics with syringe prescriptions, 1 predominantly used methamphetamine, and 2 were a couple who lived outside the town where most PWID lived in Scott County, possibly precluding sharing with others.
Participants reduced their injection risk behaviors after the SSP (Table 3B ), noting “it's not hard to find a syringe anymore,” “since the needle program's been out” and that “I give it (a needle) to them” if someone is without a new syringe. As a result, participants explained that there was no need to “use after nobody” and that “you only use a needle once.”
Participants also reported ongoing sharing of pill solutions after the HIV outbreak and the SSP, but dividing drugs in ways that minimized HIV/HCV risk (Table 3B ). For example, when backloading, participants reported using a sterile syringe to prepare the drug solution and squirt solution into each person's sterile syringe. In addition, participants reported when a pill was prepared in 1 cooker and drawn up by multiple people, only sterile syringe was used. “Dirty needles” never went in the cooker.
A few participants reported continued syringe sharing that may pose HIV/HCV risk (Table 3C ). In 2 cases, the participants with HIV shared with another person with HIV. One represented regular practice and the other represented 1-time sharing fueled by lack of a sterile syringe; in both cases, an exception seemed to be made because of HIV-positive seroconcordance. FG3 participants reported people with HIV more commonly shared with each other because they did not care that they were sharing or believed their HIV medications prevent HIV transmission. One HIV-negative participant reported sharing syringes regularly with his wife who was also HIV-negative.
Injection Frequency and Syringes Dispensed
The average number of daily injections that SSP clients reported increased between their first and most recent visits {5 times/d [interquartile range (IQR): 3–9] versus 9 times/d (IQR: 5–15), P < 0.001}. Similarly, the number of sterile syringes dispensed to clients, (distributed based on self-report of frequency of injection), increased between the first and most recent visit (Table 2 ). However, qualitative findings did not support increased frequency of injection or increased drug use.
I was (injecting) anywhere from 4 to 6 times a day (PI12).
Daily injection frequency was explored in PIs, but not FGs (Table 4A ) and the findings suggested no change or decrease in frequency of injection during the study period. Most who injected Opana did so daily and more than once per day. Those who injected other drugs (eg, heroin and methamphetamine), did so once or twice a week. When asked how the presence of the SSP and HIV in their community affected injection practices, almost all participants reported no change in injection frequency per day. One participant reported increased injection frequency because of increasing drug dependence over time. Two reported decreased injection frequency in an effort to eventually stop using drugs. Three participants had stopped using any drugs and were not injecting when interviewed (Table 1 ).
TABLE 4.: Sample Quotes: Injection Frequency Per Day* and Syringe Disposal Before and After Implementation of the Scott Country SSP, Indiana, April 4, 2015–August 30, 2015
In response to a question about satisfaction with the number of syringes received, FG1 participants explained the increases in the number of syringes dispensed per client since SSP enrollment and that this was due to reduction in syringe reuse by SSP clients over time.
One participant (PI21) described early confusion about how to report frequency of injection per day to SSP staff because of the overall high frequency of injection per day (Table 4A ).
Number of Syringes Returned
The number of used syringes that clients returned to the SSP for safe disposal increased from a median of 0 syringes (IQR: 0–35) at first visit, to a median of 57 syringes (28–105) at the most recent visit.
(Someone) brought me the big containers that had like 200 needles in them and asked me, can you give these to the health department? They could throw them out in the road, the ditch, lying out in the country somewhere, but they didn't… I said yeah. I'll give them back and I did. I don't want somebody to get hurt on them. Every now and then (I still see needles on the street) but, back then, before (the SSP) came around, yeah you could see needles lying everywhere (PI02).
Exact numbers of syringes returned were not reported in qualitative data. Table 4B, C shows general findings about syringe disposal before and after the SSP. Nearly all qualitative study participants commented generally about fewer needles on the ground and a much “cleaner” community since availability of SSP disposal containers (Table 4B ). Participants mentioned that it was common to throw syringes on the streets and see discarded needles everywhere before the SSP. All participants reported using containers for safe disposal after SSP, whether enrolled in the SSP and using their own container or using someone else's.
A few FG participants suggested that there were still people in the community throwing syringes on the ground. Only 1 of all the qualitative participants perceived that the community was worse in terms of syringes on the ground since the SSP and claimed to “find them in his yard twice as bad now” (Table 4C ).
Reusing the Same Syringe
The number of times the SSP clients used the same syringe decreased from 2 times (IQR: 1–4) to 1 time (IQR: 1–1) between first and most recent visit (Table 2 ).
I'd keep a needle for 4 or 5 weeks. And, the needle would have no numbers on it. This part would be bent, it would be hard to even get in my skin. I would use it, and use it, and use it until it broke Now, I won't (reuse). I use it 1 time before I throw it away (PI11).
All qualitative study participants reported that multiple reuse of syringes before the HIV outbreak was very common in the community (Table 5A ). Similar to SSP clients, qualitative study participants reported decreased reuse post-SSP (Table 5B ); with some instances of reuse (Table 3C ). Explanations for reuse post-SSP included lack of access to sterile syringes because of SSP nonenrollment, failure to visit the SSP to resupply, missing a visit on the SSP mobile outreach van, preference for a slightly duller syringe, and reuse of the same syringe if injecting more than once from the same pill solution.
TABLE 5.: Sample Quotes: Reusing the Same Syringe to Inject Before and After Implementation of the Scott Country SSP, Indiana, April 4, 2015–August 30, 2015
DISCUSSION
To the best of our knowledge, the Scott County SSP is the first example of an SSP implemented emergently to control an outbreak of HIV among PWID in a nonurban setting in the United States. Using both quantitative and qualitative data enhanced our ability to describe and understand behavior change among PWID in this community.21,22 23–26
We found low percentages of injection-related risk behaviors reported by SSP clients at their first visit to the SSP; only 18% reported sharing syringes to inject at enrollment. In comparison, among PWID interviewed across 20 large cities in the United States, 33% reported sharing syringes to inject, 60% reported sharing syringes to divide drugs, and 57% reported sharing other injection equipment in the past 12 months.27 16 16
Some SSP clients and qualitative study participants reported occasionally reusing and sharing syringes and other injection equipment post-SSP implementation. Syringe reuse without sharing can cause harm through increased risk of soft-tissue infections, endocarditis, collapsed veins, and embedded broken needle tips.28–30
It has been well established that SSPs do not increase drug use10,11 Table 4A ), with experience, the SSP staff became more accurate in assessing injection frequency. Second, as this quotation also illustrates, SSP clients learned to better estimate their own drug usage and sterile syringe needs. Enrolling in the SSP may have been the first time some clients needed to accurately assess their usage. As participants reported, not only did they reuse syringes less frequently after enrolling in the SSP but they had did not initially realized that they needed a new sterile syringe for every injection.
Our analysis aimed to describe injection behavior change and did not assess in detail information on receipt and linkage to other services provided by the SSP. As many SSPs throughout the United States, the Scott County program also provides, among other services, HIV testing and referral to ART and PrEP that could be imperative to reducing HIV transmission among those who continue to share in this high background prevalence setting. In a prospective cohort study among PWID in Vancouver, community HIV viral load was independently associated with HIV incidence,31 14
Several limitations must be considered in interpreting our findings. First, SSP clients and qualitative study participants may have underreported injection-related risk behaviors because of social desirability, particularly during an emergency outbreak investigation. To mitigate this potential reporting bias, both the SSP staff and qualitative study interviewers worked closely with the community to establish trust and positive rapport to encourage accurate reporting of risk behaviors. Second, routinely collected program data were limited and did not allow for multivariate analyses; for example, we did not have HIV status information for SSP clients, and therefore, could not examine whether the reported reductions in injection-related behaviors varied by awareness of one's HIV status. Third, we did not have quantitative data on PWID not enrolled in the SSP and therefore, could not directly attribute changes in injection-related behaviors to the SSP; however, several qualitative study participants did not access the SSP and described their experiences. Finally, although the qualitative study used multiple sampling methods to reach a cross-section of PWID, the experiences of qualitative study participants and SSP clients may not represent the larger PWID population in Scott County or other nonurban settings.
In conclusion, our analysis demonstrated significant rapid reductions of injection-related risk behaviors among PWID after emergency implementation of a comprehensive SSP in a nonurban community in response to the HIV outbreak in Scott County, Indiana. These findings emphasize the need for harm reduction interventions for PWID that include access to syringes and sterile injection equipment, as well as comprehensive HIV prevention services including HIV testing and referrals for PrEP, or care and ART. Future efforts to implement and strengthen nonurban SSPs might consider focusing on retaining existing clients, expanding access to other PWID in the community, including through peer-driven strategies to reach PWID for services, and strengthening referral and follow-up to address evolving health needs to ensure long-term success of such programs. Proactive establishment of SSPs in nonurban communities with PWID might help to prevent future outbreaks of HIV.
ACKNOWLEDGMENTS
The authors acknowledge the following persons who provided support for this work: Jackie Crane (Scott County Department of Health); Caitlin Conrad, Brittany Gross, and Michelle Sandoval (Indiana State Department of Health); Jon Zibbell and Philip J. Peters (Centers for Disease Control and Prevention); Cameron McCalister and Nicole Strange (Indiana University-Purdue University); Nicole Stone and James Walters (Indiana University Fairbanks School of Public Health).
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