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Trends in HCV Prevalence and Risk Factors Among People who Inject Drugs in Los Angeles County, 2012-2024
Yingbo Ma1, Ekow Kwa Sey2, Hugo Santacruz2
1Division of HIV and STD Programs, Los Angeles County Department of Public Health, Los Angeles, CA, USA. yma@ph.lacounty.gov.
AIDS and Behavior
|February 26, 2026
Summary
Hepatitis C virus (HCV) infection prevalence significantly declined among people who inject drugs in Los Angeles County. Harm reduction efforts likely contributed to reduced HCV transmission and improved outcomes.
Area of Science:
- Public Health
- Infectious Diseases
- Epidemiology
Background:
- Tracking Hepatitis C virus (HCV) prevalence is crucial for evaluating global HCV elimination strategies.
- People who inject drugs (PWID) are a key population for monitoring HCV trends due to higher infection rates.
- Understanding changes in HCV seroprevalence among PWID in Los Angeles County (LAC) informs targeted interventions.
Purpose of the Study:
- To evaluate temporal trends in HCV antibody and chronic HCV infection prevalence among PWID in LAC.
- To identify demographic and behavioral factors associated with HCV prevalence and changes over time.
Main Methods:
- Analysis of HCV antibody and RNA seroprevalence data from PWID in LAC participating in the National HIV Behavioral Surveillance.
- Data collected across multiple years: 2012, 2015, 2018, 2022, and 2024.
- Multivariable analyses were used to assess factors associated with HCV prevalence and trends.
Main Results:
- A significant decrease in HCV antibody seroprevalence was observed, from 81.2% in 2012 to 34.2% in 2024.
- Chronic HCV infection prevalence also declined from 37.1% in 2018 to 18.2% in 2024.
- The largest annual decreases were seen in participants aged ≥30 years and female PWID (9.1% annually). HCV positivity remained higher among males, those with lower education, daily injectors, and individuals with incarceration history or receptive syringe sharing.
Conclusions:
- Observed decreases in HCV prevalence suggest the positive impact of harm reduction strategies on reducing transmission among PWID in LAC.
- Continued expansion of HCV testing, treatment, and harm reduction services is essential for sustained progress and reaching underserved communities.
- Addressing disparities in HCV prevalence requires focused efforts on high-risk subgroups within the PWID population.
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