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Infectious Diseases

People with OUD are at higher risk for infectious diseases like hepatitis C (HCV), hepatitis B (HBV), HIV, skin and soft tissue infections, and other sexually transmitted infections due to behaviors associated with substance use. The National Academy of Sciences emphasizes that the epidemics of OUD, overdose, HCV, and HIV are interconnected and require combined prevention and treatment strategies.1

Medications for OUD can reduce the risk of infection by decreasing needle sharing and risky sexual behaviors. 2 However, patients entering OUD treatment may already have undiagnosed infections when starting treatment or may still be exposed while in care.

Practices screen all patients with OUD for infectious disease upon intake, conduct risk assessments, and provide basic education and counseling about the risk of infectious disease. Patients with infectious diseases should either be treated onsite or referred to care elsewhere.

Talk to your patients about how infectious diseases spread through injection and intranasal drug use, including contaminated needles, syringes, and other equipment, as well as sexual contact. Emphasize the importance of getting tested every time they engage in high-risk behavior. Patient-oriented materials that may be useful include:

If your patients continue to inject opioids, encourage them to use new, sterile needles and syringes every time, never share equipment, and access to programs where they can trade used needles for new ones. If new supplies are not available, they should clean used syringes with bleach.3 Approach these conversations with empathy and without judgment to foster trust and engagement in care, and offer patients materials such as How To Clean Your Syringe/Cómo limpiar sus jeringas (PDF - 181 KB).

During the initial intake process, you can assess a patient's risk for infectious diseases by asking about substance use behaviors and counseling them on the importance of routine testing. Many patients with hepatitis C (HCV) are asymptomatic, so it is important to screen based on risk factors rather than waiting for symptoms to develop.4 Regular infectious disease testing helps monitor changes in patient status, and for those engaging in continued high-risk behaviors, more frequent screening may be warranted.

CDC offers the following clinical guidelines:

If a patient tests positive for an infectious disease, it is important to provide targeted education and brief counseling. Report positive cases to the local health department as required. For patients at high risk of HIV, PrEP may be a valuable option to reduce the risk of infection. For more information, see Clinical Guidance for PrEP | HIV Nexus | CDC

Once you diagnose a patient with an infectious disease, act quickly to either start treatment in your practice or refer the patient to specialized care. Whenever possible, it is preferable to treat both infectious diseases and OUD within the same setting. For example, co-locating HIV and OUD treatment has been shown to improve patient outcomes for both conditions.5

Although not an infectious disease, people with OUD often present with significant wounds due to their drug use. The most common sources of wounds are the result of xylazine and injection drug use.

Xylazine

Xylazine (street name “tranq”) is a veterinary sedative not approved for human use. It is commonly used to cut fentanyl and heroin and often used with those opioids without the person's knowledge.

  • Xylazine use is associated with necrotic wounds, severe skin ulcers, soft tissue ischemia and at the most extreme, osteomyelitis and pathological fracture.6,7 Wounds can occur regardless of route of administration and at locations other than the injection site.8
  • Low-barrier treatment of these wounds8 and a surgical approach to treating the wounds6 are described in the literature and linked in the Resources.
  • Prevention: Fortunately, the risk of xylazine use can be mitigated by using xylazine test strips, which are inexpensive and can be purchased online. A detailed description on how to use the test strips is available here: Xylazine Test Strips: Quick Detection for Drug Safety.

Injection Drug Use

The risk of contracting infectious diseases due to sharing needles and injecting equipment was described earlier in this section. Injection drug use is associated with skin infections such as abscesses, cellulitis, and more serious health problems such as sepsis and gangrene. These conditions are typically the result of a nonsterile injection environment and practices (e.g., needle reuse and sharing) and wounds caused by repeated injection into the same vein.

Prevention: Excellent educational materials that describe sterile practices and wound care in detail are available for patients and providers (e.g., Wound Care & Medical Triage for People Who Use Drugs and the Programs That Serve Them | NASTAD), which could help address gaps in patient knowledge. In one study, most people (81%) who injected drugs (n=101) had developed injection-related wounds, and almost everyone took care of their own wounds. Some (15%) employed potentially harmful approaches to wound management such as manipulating the sores (e.g., squeezing, burning with hot water), applying bleach, or taking antibiotics procured on the street.9

  • Don't forget to assess patients' risk for infectious disease at the beginning of treatment or throughout treatment, especially if a person is still using illicit drugs.
  • Don't wait for a person to have stopped using substances before connecting them with care for infectious diseases.

Wound Care & Medical Triage for People Who Use Drugs and the Programs That Serve Them

This comprehensive guide provides information and recommendations regarding general health, safer use practices, common viral, fungal, parasitic, and other injection-related infections, overdose and overamp, tapering, withdrawal, medications for opioid use disorder, and seeking medical care.
Source
National Harm Reduction Technical Assistance Center (NASTAD)
Year

1. Leshner AI, Mancher M, eds. Medications for Opioid Use Disorder Save Lives. National Academies Press; 2019. doi:10.17226/25310

2. Saxon AJ, Hser YI, Woody G, Ling W. Medication-assisted treatment for opioid addiction: methadone and buprenorphine. J Food Drug Anal. 2013;21(4):S69-S72. doi:10.1016/j.jfda.2013.09.037

3. National Harm Reduction Coalition. Harm Reduction Principles. National Harm Reduction Coalition. Accessed April 28, 2025. https://harmreduction.org/about-us/principles-of-harm-reduction/

4. World Health Organization. Hepatitis C. WHO. 2024. Accessed April 28, 2025. https://www.who.int/news-room/fact-sheets/detail/hepatitis-c

5. Mizuno Y, Higa DH, Leighton CA, Mullins M, Crepaz N. Is co-location of services with HIV care associated with improved HIV care outcomes? A systematic review. AIDS Care. 2019;31(11):1323-1331. doi:10.1080/09540121.2019.1576847

6. Tosti R, Hozack BA, Tulipan JE, Criner-Woozley KT, Ilyas AM. Xylazine-Associated Wounds of the Upper Extremity: Evaluation and Algorithmic Surgical Strategy. Journal of Hand Surgery Global Online. 2024;6(5):605-609. doi:10.1016/j.jhsg.2024.05.003

7. Malayala SV, Papudesi BN, Bobb R, Wimbush A. Xylazine-Induced Skin Ulcers in a Person Who Injects Drugs in Philadelphia, Pennsylvania, USA. Cureus. 2022;14(8):e28160. doi:10.7759/cureus.28160<

8. McFadden R, Wallace-Keeshen S, Petrillo Straub K, et al. Xylazine-associated Wounds: Clinical Experience From a Low-barrier Wound Care Clinic in Philadelphia. J Addict Med. 2024;18(1). doi:10.1097/ADM.0000000000001245

9. Roose RJ, Hayashi AS, Cunningham CO. Self-Management of Injection-Related Wounds Among Injecting Drug Users. J Addict Dis. 2009;28(1). doi:10.1080/10550880802545200