Hepatitis C antibody test frequencies and positive rates in Switzerland from 2007 to 2017: a retrospective longitudinal study

ACKGROUND AND AIMS: The prevalence of chronic hepatitis C in Switzerland is currently estimated at approximately 32,000 affected individuals (0.37% of the permanent resident population). An estimated 40% of affected individuals in Switzerland is undiagnosed. The Swiss Federal Office of Public Health requires laboratories to report all positive hepatitis C virus (HCV) test results. Approximately 900 newly diagnosed cases are reported annually. The number of HCV tests performed, however, is not collected by the Federal Office of Public Health and positive rates are therefore unknown. The aim of this study was to describe the longitudinal course of the numbers of hepatitis C antibody tests and of positive rates in Switzerland for the years 2007 to 2017. METHODS: Twenty laboratories were asked to provide the number of HCV antibody tests performed and the number of positive antibody tests per year. Using data from the Federal Office of Public Health reporting system for the years 2012 to 2017, we calculated a factor to correct our values for multiple tests of the same person. RESULTS: The annual number of HCV antibody tests performed tripled linearly from 2007 to 2017 (from 42,105 to 121,266) while the number of positive HCV antibody test results increased by only 75% over the same period (from 1360 to 2379). The HCV antibody test positive rate steadily decreased from 3.2% in 2007 to 2.0% in 2017. After correction for multiple tests per person, the person-level HCV antibody tested positive rate decreased from 2.2% to 1.7% from 2012 to 2017. CONCLUSION: In the Swiss laboratories considered, more HCV antibody tests were performed each year in the period (2007–2017) before and during the approval of the new hepatitis C drugs. At the same time, the HCV antibody positive rates decreased, both on a per-test as well as a per-person level. This study is the first to describe the evolution of tests performed and of positive rates for HCV antibody in Switzerland at the national level over several years. In order to more accurately guide future measures to achieve the goal of eliminating hepatitis C by 2030, we recommend annual collection and publication of positive rates by health authorities, along with mandatory reporting of numbers of tests and people treated

Hepatitis C: a changing epidemic.

Approximately 3% of the world population is estimated to have a chronic hepatitis C virus (HCV) infection and 500,000 individuals die from its consequences yearly. Persons who inject drugs (PWID) bear the majority of the disease burden in high-income countries. Drug substitution programmes have helped reduce HCV transmissions among PWID. However, recent epidemics of sexually transmitted HCV infections in HIV-infected men who have sex with men demonstrated the changing nature of the HCV epidemic. HCV therapy is undergoing a revolution, as new interferon-free, oral treatments eradicate HCV infections in almost all treated patients. As a consequence, the eradication of HCV has become a matter of debate and is becoming an important future public health target. However, for this to be achieved, many challenges need to be addressed, including the poor uptake of HCV testing, the high cost of the new antiviral combinations and the high frequency of re-infections after treatment in some populations

Hepatitis C virus elimination in Swiss opioid agonist therapy programmes - the SAMMSU cohort.

BACKGROUND Hepatitis C virus (HCV) infections in Switzerland are mainly related to intravenous drug use. Since 2017, all patients with chronic hepatitis C can be treated with direct-acting antivirals (DAAs) irrespective of fibrosis stage. In March 2019, the Federal Office of Public Health (FOPH) published guidelines for HCV management in people who use drugs. To achieve HCV elimination by 2030, 80% treatment uptake is necessary. AIM To evaluate the benefit of interferon-based and interferon-free HCV treatment in patients on opioid agonist therapy (OAT) and monitor HCV elimination, a 2-year study commissioned by the FOPH and conducted within the Swiss Association for the Medical Management in Substance Users (SAMMSU) cohort was performed. METHODS Since 2014, the SAMMSU cohort has recruited OAT patients from eight different centres throughout Switzerland. In addition to yearly follow up, cross-sectional data were collected at the time-points 1 May 2017, 1 May 2018 and 1 May 2019. HCV treatment uptake, adherence and success, as well as reinfection rates, the effect of early versus late treatment and the efficacy of the “treatment-as-prevention” approach were analysed. RESULTS Between 1 May 2017 and 1 May 2019, the number of patients enrolled into the SAMMSU cohort increased from 623 to 900: 78% were male, the median age was 45 years, 81% had ever used intravenous drugs, 13% were human immunodeficiency virus (HIV) positive and 66% were HCV antibody positive. HCV treatment up to 2012 was exclusively interferon based (maximum 21 patients/year) and since 2016 exclusively interferon free (102 patients in 2017). Treatment success increased from 57% (112/198; interferon based) to 97% (261/268; interferon free) irrespective of cirrhosis or prior non-response to interferon. Simultaneously, treatments became shorter and better tolerated in the interferon-free era, resulting in fewer preterm stops (17% vs 1%) and adherence problems (9% vs 2%). Between 2015 and 2018, the proportion of patients with no/mild fibrosis (F0/F1) at first HCV treatment increased from 0% to 61%. Earlier treatment reduced the duration of infectiousness. Between 1 May 2017 and 1 May 2019, the proportion of chronic hepatitis C patients ever treated increased from 62% (198/321) to 80% (391/490). In parallel, the HCV-RNA prevalence among HCV antibody-positive patients declined from 36% (139/385) to 19% (113/593). The reinfection rate after successful treatment was 2.7/100 person-years. The number of HCV first diagnoses per year decreased from >20 up to 2015 to <10 in 2017 and 2018. CONCLUSION With nearly 100% DAA treatment success and a low reinfection rate, treatment uptake directly translates into a reduction of HCV-RNA prevalence. Eighty percent treatment uptake is feasible in OAT patients, and adherence and treatment success are not worse than in other populations. Duration of infectiousness and thus HCV transmission can be reduced by early detection and treatment of chronic hepatitis C

Mortality and morbidity related to hepatitis C virus infection in hospitalized adults-A propensity score matched analysis

The World Health Organization (WHO) aims to reduce HCV mortality, but estimates are difficult to obtain. We aimed to identify electronic health records of individuals with HCV infection, and assess mortality and morbidity. We applied electronic phenotyping strategies on routinely collected data from patients hospitalized at a tertiary referral hospital in Switzerland between 2009 and 2017. Individuals with HCV infection were identified using International Classification of Disease (ICD)-10 codes, prescribed medications and laboratory results (antibody, PCR, antigen or genotype test). Controls were selected using propensity score methods (matching by age, sex, intravenous drug use, alcohol abuse and HIV co-infection). Main outcomes were in-hospital mortality and attributable mortality (in HCV cases and study population). The non-matched dataset included records from 165,972 individuals (287,255 hospital stays). Electronic phenotyping identified 2285 stays with evidence of HCV infection (1677 individuals). Propensity score matching yielded 6855 stays (2285 with HCV, 4570 controls). In-hospital mortality was higher in HCV cases (RR 2.10, 95%CI 1.64 to 2.70). Among those infected, 52.5% of the deaths were attributable to HCV (95%CI 38.9 to 63.1). When cases were matched, the fraction of deaths attributable to HCV was 26.9% (HCV prevalence: 33%), whilst in the non-matched dataset, it was 0.92% (HCV prevalence: 0.8%). In this study, HCV infection was strongly associated with increased mortality. Our methodology may be used to monitor the efforts towards meeting the WHO elimination targets and underline the importance of electronic cohorts as a basis for national longitudinal surveillance

Recommendations for the Management of Hepatitis C Virus Infection Among People Who Inject Drugs

In the developed world, the majority of new and existing hepatitis C virus (HCV) infections occur among people who inject drugs (PWID). The burden of HCV-related liver disease in this group is increasing, but treatment uptake among PWID remains low. Among PWID, there are a number of barriers to care that should be considered and systematically addressed, but these barriers should not exclude PWID from HCV treatment. Furthermore, it has been clearly demonstrated that HCV treatment is safe and effective across a broad range of multidisciplinary healthcare settings. Given the burden of HCV-related disease among PWID, strategies to enhance HCV assessment and treatment in this group are urgently needed. These recommendations demonstrate that treatment among PWID is feasible and provides a framework for HCV assessment, management, and treatment. Further research is needed to evaluate strategies to enhance assessment, adherence, and SVR among PWID, particularly as new treatments for HCV infection become availabl

Incidence of sexually transmitted infections and association with behavioural factors: Time-to-event analysis of a large pre-exposure prophylaxis (PrEP) cohort.

OBJECTIVES Our objective was to obtain long-term data on the incidence of sexually transmitted infections (STIs) and their association with behavioural factors after widespread pre-exposure prophylaxis (PrEP) implementation. METHODS This was a time-to-event analysis of a national PrEP cohort in Switzerland (SwissPrEPared study). Participants were people without HIV interested in taking PrEP with at least two STI screening visits. Primary outcomes were incidence rate of gonorrhoea, chlamydia, and syphilis. The association between behavioural factors and STI diagnosis was expressed using hazard ratios. We adjusted for testing frequency and calendar year. RESULTS This analysis included 3907 participants enrolled between April 2019 and April 2022, yielding 3815.7 person-years of follow-up for gonorrhoea (15 134 screenings), 3802.5 for chlamydia (15 141 screenings), and 3858.6 for syphilis (15 001 screenings). The median age was 39 years (interquartile range [IQR] 32-47), 93.8% (n = 3664) identified as men who have sex with men (MSM). The incidence was 22.8 (95% confidence interval [CI] 21.3-24.4) per 100 person-years for gonorrhoea, 26.3 (95% CI 24.7-28.0) for chlamydia, and 4.4 (95% CI 3.8-5.1) for syphilis. Yearly incidence rates decreased between 2019 (all bacterial STIs: 81.6; 95% CI 59.1-109.9) and 2022 (all bacterial STIs: 49.8; 95% CI 44.6-55.3). Participants reporting chemsex substance use were at higher risk of incident STIs, as were those reporting multiple sexual partners. Younger age was associated with a higher risk of gonorrhoea and chlamydia. CONCLUSIONS Incidence rates of bacterial STIs decreased over time. Young MSM, those with multiple partners, and those using chemsex substances were at increased risk of STIs

Adherence to once-daily and twice-daily direct acting antiviral therapy for hepatitis C infection among people with recent injection drug use or current opioid agonist therapy

BACKGROUND This study investigated adherence and associated factors among people with recent injection drug use (IDU) or current opioid agonist therapy (OAT) and compared once-daily to twice-daily hepatitis C virus (HCV) direct-acting antiviral (DAA) therapy. METHODS SIMPLIFY and D3FEAT are international, multicenter studies that recruited participants with recent IDU (previous 6 months; SIMPLIFY, D3FEAT) or current OAT (D3FEAT) between March 2016 and February 2017 in 8 countries. Participants received sofosbuvir/velpatasvir (once daily; SIMPLIFY) or paritaprevir/ritonavir/ombitasvir, dasabuvir (twice daily) ± ribavirin (D3FEAT) for 12 weeks administered in electronic blister packs. We evaluated overall adherence (proportion of prescribed doses taken) and nonadherence (<90% adherent) between dosing patterns. RESULTS Of 190 participants, 184 (97%) completed treatment. Median adherence was 92%, with higher adherence among those receiving once-daily vs twice-daily therapy (94% vs 87%, P = .005). Overall, 40% of participants (n = 76) were nonadherent (<90% adherent). Recent stimulant injecting (odds ratio [OR], 2.48 [95% confidence interval {CI}, 1.28-4.82]), unstable housing (OR, 2.18 [95% CI, 1.01-4.70]), and twice-daily dosing (OR, 2.81 [95% CI, 1.47-5.36]) were associated with nonadherence. Adherence decreased during therapy. Sustained virologic response was high in nonadherent (89%) and adherent populations (95%, P = .174), with no difference in SVR between those who did and did not miss 7 consecutive doses (92% vs 93%, P = .897). CONCLUSIONS This study demonstrated high adherence to once- and twice-daily DAA therapy among people with recent IDU or currently receiving OAT. Nonadherence described did not impact treatment outcomes, suggesting forgiveness to nonadherence

Incidence of sexually transmitted infections and association with behavioural factors: Time-to-event analysis of a large pre-exposure prophylaxis (PrEP) cohort

OBJECTIVES: Our objective was to obtain long-term data on the incidence of sexually transmitted infections (STIs) and their association with behavioural factors after widespread pre-exposure prophylaxis (PrEP) implementation. METHODS: This was a time-to-event analysis of a national PrEP cohort in Switzerland (SwissPrEPared study). Participants were people without HIV interested in taking PrEP with at least two STI screening visits. Primary outcomes were incidence rate of gonorrhoea, chlamydia, and syphilis. The association between behavioural factors and STI diagnosis was expressed using hazard ratios. We adjusted for testing frequency and calendar year. RESULTS: This analysis included 3907 participants enrolled between April 2019 and April 2022, yielding 3815.7 person-years of follow-up for gonorrhoea (15 134 screenings), 3802.5 for chlamydia (15 141 screenings), and 3858.6 for syphilis (15 001 screenings). The median age was 39 years (interquartile range [IQR] 32-47), 93.8% (n = 3664) identified as men who have sex with men (MSM). The incidence was 22.8 (95% confidence interval [CI] 21.3-24.4) per 100 person-years for gonorrhoea, 26.3 (95% CI 24.7-28.0) for chlamydia, and 4.4 (95% CI 3.8-5.1) for syphilis. Yearly incidence rates decreased between 2019 (all bacterial STIs: 81.6; 95% CI 59.1-109.9) and 2022 (all bacterial STIs: 49.8; 95% CI 44.6-55.3). Participants reporting chemsex substance use were at higher risk of incident STIs, as were those reporting multiple sexual partners. Younger age was associated with a higher risk of gonorrhoea and chlamydia. CONCLUSIONS: Incidence rates of bacterial STIs decreased over time. Young MSM, those with multiple partners, and those using chemsex substances were at increased risk of STIs