Risk of Infectious Diseases

Individuals with opioid use disorder can be at increased risk of contracting infectious diseases, such as hepatitis C virus (HCV), hepatitis B virus (HBV), human Immunodeficiency virus (HIV), and other sexually transmitted diseases. These individuals face higher risk because they may be more likely to engage in risky behaviors associated with substance use. The National Academy of Sciences notes that “It is increasingly evident that the ongoing epidemics of [opioid use disorder], opioid overdose, HCV, and HIV in the United States are linked and warrant combined evidence-based interventions for prevention and treatment.”1

Research has indicated that participation in medication-assisted treatment (MAT) can decrease an individual’s risk of contracting infectious diseases as they are less likely to engage in sharing needles or risky sexual behaviors while in treatment.2 However, patients entering MAT may already have contracted these diseases (although many do not know they are infected) or may be exposed while in treatment.

North Star

Practices screen all MAT patients 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.  

How Do You Do It?

Educate Patients on the Risks

Providers should talk to their patients about the risks of intravenous and intranasal drug use and how viruses can spread through blood across contaminated needles, syringes, and other equipment as well as through sexual intercourse. Providers need to emphasize the importance of getting tested for these infectious diseases every time the person engages in high-risk behavior.

Patient-oriented materials that may be useful include:

If patients continue to inject illicit opioids, providers should take a harm reduction approach, focusing on how patients can decrease the risk associated with injection drug use by using a new, sterile needle and syringe every time, never sharing equipment, or participating in a needle exchange program to get new syringes. If new, unused needles and syringes are not available, patients should clean them thoroughly with bleach before using them again. Because of added stigma surrounding injection drug use, providers need to approach these conversations in an empathetic and nonjudgmental manner.

Implement Routine Screening for Infectious Diseases

During the initial intake process, providers should assess a patient’s risk for infectious diseases by asking about risky behaviors associated with substance use and then counsel patients on the importance of getting tested. Infectious disease testing should be repeated on a regular basis as defined by the practice to monitor any changes in patient status. If some patients still report engaging in high-risk behaviors later in treatment, providers may use clinical judgment to screen for infectious diseases more frequently. Individuals with HCV are often asymptomatic, so providers should not wait until a patient reports feeling sick to screen for this disease.3

Test may include the following:

  • Liver function tests can inform medication selection and dosage as severe liver disease may contraindicate medications to treat opioid use disorder.4
  • Hepatitis B and C serology can indicate the need for hepatitis treatment for patients who have positive test results.4 For HCV, antibody tests (i.e., anti-HCV tests) should be performed, and any reactive antibody tests should be confirmed with a ribonucleic acid (RNA) polymerase chain reaction (PCR). For HBV, patients should be tested for surface antigens (i.e., HBsAg); surface antibodies (i.e., anti-HBs or HBsAb); or core antibodies (i.e., anti-HBc or HBcAb).
  • HIV serology can help identify HIV status, which may indicate the need for antiretroviral treatment for patients who are HIV positive or prevention measures for patients who are at high risk.4 A “4th generation” HIV test should be used to detect HIV antibodies and p24 antigens.
  • Tests for other sexually transmitted diseases as clinically indicated may include syphilis serology (Treponema pallidum particle agglutination [TPPA] assay) or urine tests for gonorrhea or chlamydia.

During routine patient visits, providers should also ask patients questions about their drug use or risky behaviors to determine the patient’s risk for contracting an infectious disease. Examples of tools that can be used for this discussion include the Hepatitis Risk Assessment Tool developed by CDC (PDF—171 KB) and the STD, HIV, and Hepatitis Risk Assessment from the Minnesota Department of Health.

Patients who screen positive for the presence or risk of infectious diseases should receive targeted education and brief counseling about these conditions. Positive cases should be reported to the local health department. Patients at high risk of contracting HIV may be good candidates for a preexposure prophylaxis regimen. This daily oral dose of medication can help prevent individuals at high risk from contracting the virus. Learn more about counseling and testing for HCV (PDF—2.05 MB) and HIV

Initiate or Connect Patients With Care

After diagnosing patients with an infectious disease, providers should move quickly to either initiate treatment for these conditions within the practice or connect these individuals with specialized, external care. Ideally, practices would be able to provide integrated treatment of both infectious diseases and opioid use disorder in primary care. Colocation of treatment for HIV and opioid use disorder, for example, has shown improved patient outcomes for both conditions.1

Learn more about Substance Abuse Treatment for Persons With HIV/AIDS and Addressing Viral Hepatitis in People With Substance Use Disorders.

What Not To Do

  • 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.


  1. National Academies of Sciences, Engineering, and Medicine. Medications for Opioid Use Disorder Save Lives. Washington, DC: National Academies Press; March 2019. http://www.nationalacademies.org/hmd/Reports/2019/medications-for-opioid-use-disorder-save-lives.aspx. Accessed June 20, 2019.
  2. Saxon AJ, Hser YI, Woody G, et al. Medication-assisted treatment for opioid addiction: methadone and buprenorphine. J Food Drug Anal 2013;1(4):S69-S72. https://www.ncbi.nlm.nih.gov/pubmed/24436573. Accessed June 12, 2019.
  3. Providers Clinical Support System. Opioid Addiction With Medical Co-Morbidities. East Providence, RI: Providers Clinical Support System; 2017. https://pcssnow.org/resource/opioid-addiction-psychiatric-comorbidities/. Accessed June 12, 2019.
  4. Substance Abuse and Mental Health Services Administration. Treatment Improvement Protocol63: Medications for Opioid Use Disorder. Rockville, MD: Substance Abuse and Mental Health Services Administration; 2018. Publication No. SMA18-5063. https://store.samhsa.gov/product/TIP-63-Medications-for-Opioid-Use-Disorder-Full-Document-Including-Executive-Summary-and-Parts-1-5-/SMA19-5063FULLDOC. Accessed June 12, 2019.