Until the COVID-19 pandemic, San Francisco’s hepatitis C virus (HCV) elimination initiative, End Hep C SF, was expanding and refining HCV testing and treatment strategies citywide, making progress toward local HCV elimination goals. Although a shelter-in-place health order issued in March 2020 categorized HCV testing as an “essential service,” most HCV testing and treatment immediately stopped until COVID-19–safe protocols could be implemented. During the 14 months of pandemic-related organizational closures, End Hep C SF transitioned to a 100% virtual model, maintaining regularly scheduled meetings. Community-based HCV antibody testing decreased 80% from February to April 2020, and HCV treatment initiation also decreased, although both services started to rebound in mid-to-late 2020, partially as a result of End Hep C SF collaborations. End Hep C SF service providers, clinicians, and advocates reported that the continuous communication and common agenda of End Hep C SF—2 principles of the collective impact initiative—served as a familiar touchpoint and helpful source of information during this isolating and uncertain time. Ultimately, End Hep C SF allowed us to continue HCV elimination strategies through 6 lessons learned: maintaining HCV treatment access through telehealth and mobile services; leveraging research studies that provided HCV testing and treatment; offering HCV screening and linkage to care in tandem with COVID-19–related initiatives; being flexible and inventive, such as administering HCV treatment to residents of shelter-in-place hotels; establishing a data dashboard to track HCV testing and treatment; and relying on partnerships to solve problems and avoid burnout.

BACKGROUND: With the introduction of direct-acting antivirals to treat and cure hepatitis C virus (HCV) infection, HCV elimination is achievable. In 2017, San Francisco's HCV elimination initiative, End Hep C SF, generated an estimate of city-wide HCV prevalence in 2015, but only incorporated limited information about population HCV treatment. Using additional data and updated methods, we aimed to update the 2015 estimate to 2019 and provide a more accurate estimate of the number of people with untreated, active HCV infection overall and in key subgroups - people who inject drugs (PWID), men who have sex with men (MSM), and low socioeconomic status transgender women (low SES TW). METHODS: Our estimates are based on triangulation of data from blood bank testing records, cross-sectional and longitudinal observational studies, and published literature. We calculated subpopulation estimates based on biological sex, age and/or HCV risk group. When multiple sources of data were available for subpopulation estimates, we calculated an average using inverse variance weighting. Plausible ranges (PRs) were conservatively estimated to convey uncertainty. RESULTS: The total number of people estimated to have anti-HCV antibodies in San Francisco in 2019 was 22,585 (PR:12,014-44,152), with a citywide seroprevalence of 2.6% (PR:1.4%-5.0%) - similar to the 2015 estimate of 21,758 (PR:10,274-42,067). Of all people with evidence of past or present infection, an estimated 11,582 (PR:4,864-35,094) still had untreated, active HCV infection, representing 51.3% (PR:40.5%-79.5%) of all people with anti-HCV antibodies, and 1.3% (PR:0.6%-4.0%) of all San Franciscans. PWID comprised an estimated 2.8% of the total population of San Francisco, yet 73.1% of people with anti-HCV antibodies and 90.4% (n=10,468, PR:4,690-17,628) of untreated, active HCV infections were among PWID. MSM comprised 7.8% of the total population, yet 11.7% of people with anti-HCV antibodies and 1.0% (n=119, PR:0-423) of those with untreated active infections. Low SES TW comprised an estimated 0.1% of the total population, yet 1.4% of people with HCV antibodies and 1.6% (n=183, PR:130-252) of people with untreated active infections. CONCLUSIONS: Despite the above-average number (2.6%) of people with anti-HCV antibodies, we estimate that only 1.3% (PR:0.6%-4.0%) of all San Francisco residents have untreated, active HCV infection - likely a reflection of San Francisco's robust efforts to diagnose infection among high-risk groups and initiate curative treatment with as many people as possible. While plausible ranges of infections are wide, these findings indicate that while the overall number of people with anti-HCV antibodies may have increased slightly, the number of people with active HCV infection may have decreased slightly since 2015. This estimate improves upon the 2015 calculations by directly estimating the impact of curative treatment citywide and in subgroups. However, more research is needed to better understand the burden of HCV disease among other subgroups at high risk, such as Blacks/African Americans, people with a history of injection drug use (but not injecting drugs in the last 12 months), people who are currently or formerly incarcerated, and people who are currently or formerly unhoused.

Background In 2017, San Francisco’s initiative to locally eliminate hepatitis C virus (HCV) as a public health threat, End Hep C SF, generated an estimate of city-wide HCV prevalence in 2015, but only incorporated limited information about population HCV treatment. Using additional data and updated methods, we aimed to update the 2015 estimate to 2019 and provide a more accurate estimate of the number of people with untreated, active HCV infection overall and in key subgroups–people who inject drugs (PWID), men who have sex with men (MSM), and low socioeconomic status transgender women (low SES TW). Methods Our estimates are based on triangulation of data from blood bank testing records, cross-sectional and longitudinal observational studies, and published literature. We calculated subpopulation estimates based on biological sex, age and/or HCV risk group. When multiple sources of data were available for subpopulation estimates, we calculated an average using inverse variance weighting. Plausible ranges (PRs) were conservatively estimated to convey uncertainty. Results The total number of people estimated to have anti-HCV antibodies in San Francisco in 2019 was 22,585 (PR:12,014–44,152), with a citywide seroprevalence of 2.6% (PR:1.4%–5.0%)–similar to the 2015 estimate of 21,758 (PR:10,274–42,067). Of all people with evidence of past or present infection, an estimated 11,582 (PR:4,864–35,094) still had untreated, active HCV infection, representing 51.3% (PR:40.5%–79.5%) of all people with anti-HCV antibodies, and 1.3% (PR:0.6%–4.0%) of all San Franciscans. PWID comprised an estimated 2.8% of the total population of San Francisco, yet 73.1% of people with anti-HCV antibodies and 90.4% (n = 10,468, PR:4,690–17,628) of untreated, active HCV infections were among PWID. MSM comprised 7.8% of the total population, yet 11.7% of people with anti-HCV antibodies and 1.0% (n = 119, PR:0–423) of those with untreated active infections. Low SES TW comprised an estimated 0.1% of the total population, yet 1.4% of people with HCV antibodies and 1.6% (n = 183, PR:130–252) of people with untreated active infections. Conclusions Despite the above-average number (2.6%) of people with anti-HCV antibodies, we estimate that only 1.3% (PR:0.6%–4.0%) of all San Francisco residents have untreated, active HCV infection–likely a reflection of San Francisco’s robust efforts to diagnose infection among high-risk groups and initiate curative treatment with as many people as possible. While plausible ranges of infections are wide, these findings indicate that while the overall number of people with anti-HCV antibodies may have increased slightly, the number of people with active HCV infection may have decreased slightly since 2015. This estimate improves upon the 2015 calculations by directly estimating the impact of curative treatment citywide and in subgroups. However, more research is needed to better understand the burden of HCV disease among other subgroups at high risk, such as Blacks/African Americans, people with a history of injection drug use (but not injecting drugs in the last 12 months), people who are currently or formerly incarcerated, and people who are currently or formerly unhoused.