Primary findings of the described study indicate that participants reporting a history of SSTIs in the prior year were likely to partake in a variety of unsafe injection practices. While skin cleaning methods prior to injection did not exhibit significant correlations with a history of IDU-related SSTIs, the type of water sources used for drug dilution did. Females are up to three times more likely to report a history of SSTIs in comparison with males, leading us to believe that there may be sociocultural and geographic factors in the rural setting contributing to such findings. Although the anatomical location of injection did not bear a significant correlation to SSTI prevalence, the type of injection—such as ‘skin-popping’ (subcutaneous), ‘muscling’ (intramuscular), or intravenous—demonstrated significance; individuals reporting subcutaneous and intramuscular injection practices were significantly more likely to report a history of SSTIs compared to those injecting intravenously. Additionally, individuals able to regularly inject on their first attempt (e.g., always or most of the time) were significantly less likely to report a history of SSTIs. Lastly, individuals reporting a history of IDU-related SSTIs within the year prior to survey response cited several treatment methods, including both at-home remedies and professional medical care.
A number of studies have investigated and found similar trends of unsafe injection practices correlating to higher risk of SSTIs among PWID; however, many of these studies are in the context of urban or suburban populations, rather than in rural settings. Similar to our study, several others investigating urban samples have reported higher incidence of IDU-related SSTIs among females [4, 14, 29]. Tuchman  found that urban females were more likely to initiate their injection drug use after being influenced by other females and commonly relied on others to inject for them, citing inability to inject themselves and difficulty finding an injection site as primary factors driving their decision . Such circumstances increase their risk of utilizing unsafe injection practices and may lend to the higher rates of SSTIs among females who inject drugs. In the context of rural populations, the gender composition of and interactions among social networks may differ in comparison with urban settings. Cultural norms among rural populations are also different than those in urban areas, potentially serving as additional factors lending to higher rates of SSTIs among females in comparison with males in rural settings.
Site of injection has also been cited as a common factor associated with IDU-related SSTIs. Similar to our findings, Smith et al. , Phillips et al. , and Murphy et al.  revealed ‘skin-popping’ (subcutaneous injection) as a common risk factor associated with IDU-related SSTIs in urban populations [20, 26, 29]. Our findings among PWID in rural areas are consistent with their urban peers, suggesting that both populations use higher-risk sites via either ‘skin-popping’ or ‘muscling’ for injection practices. It should be kept in mind that the extent to which overall duration of injection use, and related health vulnerabilities, might be a contributing, or even driving, factor for this finding is a remaining question in the context of interpreting results of this cross-sectional study (i.e., those who have injected over longer periods of time may have greater challenges locating a viable vein for injection use).
Those citing a history of SSTIs reported the use of a variety of both professional medical treatments and at-home remedies. These findings are consistent with existing literature surrounding urban populations. Monteiro et al.  described an urban population of PWID often utilizing emergency medical services to treat SSTIs, while also reporting the use of at-home abscess drainage by non-medical personnel . Although findings are similar between urban and rural populations, individuals residing in rural areas often experience a variety of health-related disparities that may serve as barriers to accessing proper medical care . Among other factors, obstacles in accessing adequate health care in rural areas and stigma attached to seeking care for an injection-related health issue may contribute to the use of at-home remedies for the treatment of IDU-related SSTIs rather than seeking medical treatment.
Similar to our findings, Wright et al. (2020) found no significant relationship between skin cleaning prior to injection and SSTI history among a larger urban population, insinuating that skin cleaning may not serve as a strong protective factor against infection (Wright et al. 2020). However, given that our results present skin cleaning methods used at the time of survey response, rather than the skin cleaning methods used at the time of infection, these results may be indicative of changes in skin cleaning behaviors among PWID following infection in order to help prevent the development of further SSTIs. Contrarily, several studies suggest that skin cleaning methods are a significant predictor within urban populations. Smith et al.  and Murphy et al.  both present the use of alcohol for skin cleaning prior to injection as a significant protective factor against IDU-related SSTIs in urban populations [20, 29]. Similarly, Phillips and Stein  cited infrequent skin cleaning prior to injection as a common risk factor associated with IDU-related SSTIs among an urban population . Urban and rural populations may be impacted differently by skin cleaning practices despite partaking in similar techniques. Rural populations often experience several barriers when accessing syringe exchange programs . Such barriers may place rural populations at a disadvantage for obtaining skin cleaning supplies, such as alcohol wipes, in comparison with individuals residing in urban areas. This may contribute to the differences in skin cleaning significance in the context of IDU-related SSTIs between urban and rural populations who inject drugs. However, based on the contradictory findings between several studies, further research is needed to determine the role of skin cleaning methods and their effectiveness in preventing the development of SSTIs.
Contrary to our results, several studies have found that the anatomical location of injection is significantly correlated with risk of infection. Although our results suggest that individuals injecting into their hands and upper arms were slightly more likely to report a history of SSTI in comparison with individuals injecting into their cubital fossa, there was no significant correlation found. Conversely, past literature surrounding urban samples demonstrates that injection into either upper and lower extremities or the groin region corresponds with history of infection [6, 14].
Additionally, the majority of our sample cited the use of methamphetamine as their primary drug of choice. Although our study found no significant correlation between primary drug of choice and history of SSTI, both Murphy et al.  and Phillips and Stein  reported the use of ‘speedball,’ or heroin mixed with cocaine, to be commonly associated with IDU-related SSTIs in urban populations [20, 25]. Access to and preference of substances may differ between urban and rural populations, potentially lending to the differences between infections related to the substance injected.
Lastly, our study presents water source for drug dilution—whether sterile or unsterile—as a significant risk factor associated with reporting a history of SSTIs among this rural population. Although significance is not reported, Phillips and Stein’s  findings suggest that PWID in urban populations also use a combination of sterile and non-sterile water sources to inject their drugs . Likewise, despite respondents not reporting the use of public or private toilet water among this sample, Harris et al. (2020) report the use of toilet and puddle water or water alternatives, such as cola or lemon juice, used for injecting, which may further lend to risk of SSTI (Harris et al. 2020). Such results indicate that both rural and urban populations partake in risk behaviors associated with water sources and both populations are at risk of developing SSTIs related to their water sources and usage. Further investigation is required to determine the specific relationship between SSTI risk and water source, because although unsterile water sources lend to overall risk of SSTI, individuals with a history of SSTI may also be more likely to seek out sterile water sources to help prevent related infections.
Overall, higher-risk injection practices were common among participants reporting a history of SSTIs living in rural areas. These results are similar to comparative studies conducted among urban and suburban populations. These findings suggest that educational materials targeting PWID not in treatment should encompass a variety of injection behaviors—including ‘skin-popping’ (subcutaneous injection) or ‘muscling’ (intramuscular injection); proper skin cleaning practices; and the use of sterile water sources for drug dilution. Future studies should aim to understand social determinants and cultural factors, such as social networks, present in rural populations which may influence risky injection practices and the general barriers of safer injection practices to prevent SSTIs. With females being up to three times more likely to report a history of infection, future studies should investigate risk factors that are unique to females who inject drugs in rural communities. Given the increasing prevalence of methamphetamine, future research should also focus on the differences in injection practices between people who use methamphetamine as their primary drug of choice versus heroin or cocaine.
Urban hospitals and clinical practices witness high rates of emergency department visits and hospitalizations related to infectious comorbidities associated with injection drug use . Our results suggest that rural populations partake in similar risky behaviors associated with developing bacterial infections and seek out similar medical and non-medical treatments for SSTIs as urban populations. However, rural-dwelling individuals may experience more frequent barriers when attempting to access proper health care services . This places rural populations at a high risk of experiencing life-threatening sequelae. Therefore, rural hospitals should consider partnering with outreach organizations and/or pharmacies to target PWID with better wound education, safer injection practices, and education regarding when it is safe to treat their infections at home versus when to seek medical treatment. By introducing such proactive intervention and prevention methods in both the clinical and public health setting, hospitals and clinical practices will potentially see decreases in emergency department visits and hospitalizations associated with infectious comorbidities related to injection drug use.
Public health implications
The opioid epidemic is one of the most pressing public health crises of our time. Co-morbidities associated with injection drug use, namely skin and soft tissue infections, place a large financial and care burden on public health agencies and clinical settings . Syringe exchange programs have the potential to serve as a cornerstone in preventing and minimizing the effects of SSTIs as they relate to IDU. Given their expansive coverage across networks of people who inject drugs, syringe exchange programs should consider implementing or expanding existing early prevention and education materials specifically targeting risky injection practices as they relate to SSTIs. Additionally, these public health programs should consider providing resources on proper treatment methods and medical resources for individuals who have already developed an infection. Such prevention materials are one of the first lines of defense in combatting infectious co-morbidities associated with injection drug use and have the potential to make a widespread impact on both populations of people who inject drugs and the notable workload placed on hospitals to care for such patients.
This study should be considered in the context of several limitations: (1) the data presented was collected using a one-time cross-sectional approach, potentially introducing recall bias; (2) the prevalence of skin and soft tissue infections among survey respondents was estimated based self-reported infections within the year prior to survey response and could be skewed; (3) the sample size was relatively small, with all respondents being clients of Vivent Health’s statewide syringe exchange program and could impact power; and (4) the use of respondent driven sampling may underestimate the variability within populations because of the tendency of participants recruiting others with similar characteristics.