HCV disease burden and population segments in Switzerland.

BACKGROUND: Switzerland has made strides towards hepatitis C virus elimination, but as of 2019, elimination was not guaranteed. However, political interest in viral hepatitis has been increasing. We sought to develop a better understanding of Switzerland's progress towards HCV elimination and the profile of remaining HCV-RNA-positive patients. METHODS: A previously described Markov model was updated with recent diagnosis and treatment data and run to generate new forecasts for HCV disease burden. Two scenarios were developed to evaluate HCV morbidity and mortality under the status quo and a scenario that achieves the Swiss Hepatitis Strategy Elimination targets. Next, an analysis was conducted to identify population segments bearing a high burden of disease, where future elimination efforts could be directed. RESULTS: At the beginning of 2020, an estimated 32 100 viremic infections remained in Switzerland (0.37% viremic prevalence). Adult (≥18 years of age) permanent residents born abroad represented the largest subpopulation, accounting for 56% of HCV infections. Thirteen countries accounted for ≥60% of viremic infections amongst permanent residents born abroad, with most people currently residing in Zurich, Vaud, Geneva, Bern, Aargau and Ticino. Amongst Swiss-born HCV-RNA-positive persons, two-thirds had a history of IDU, corresponding to 33% of total infections. CONCLUSIONS: In Switzerland, extra efforts for diagnosis and linkage to care are warranted in foreign-born populations and people with a history of drug use. Population-level measures (eg increasing the number of providers, increase screening) can identify patients who may have otherwise fallen through the gaps or avoided care because of stigma.

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.

Oral antibiotic therapy in people who inject drugs (PWID) with bacteraemia.

Bacterial infections are a major cause of morbidity and mortality in people who inject drugs (PWID). Patients with bacteraemia have a particularly high risk of complications and are usually treated with intravenous antibiotics. Intravenous treatment is challenging in certain PWID because of difficult venous access and a high rate of catheter-associated complications. Therefore, oral treatment alternatives must be considered. This review discusses the potential options for oral antimicrobial treatment of gram-positive and gram-negative bacteraemia in PWID and the evidence for them. Data on oral antibiotic treatment of bacteraemia in PWID is scarce. Whenever possible, a course of intravenous antibiotic treatment should precede the switch to an oral regimen. For Staphylococcus aureus bacteraemia, there is growing evidence that initial intravenous antibiotics can be switched to oral treatment (e.g., a fluoroquinolone and rifampin or linezolid) when the patient is clinically stable and source control has been achieved. However, regimen selection remains challenging due to pharmacokinetic/pharmacodynamic issues, potential toxicity and drug-drug interactions of oral antibiotics. For some streptococcal bacteraemia, oral amoxicillin is probably a reasonable option. The best existing evidence for oral antibiotic treatment is for gram-negative bacteraemia, which, if susceptible, can be treated successfully with oral fluoroquinolones. Oral antibiotic options for fluoroquinolone-resistant gram-negative bacteraemia are very limited, although in selected patients oral trimethoprim-sulfamethoxazole can be considered. In conclusion, treatment of bacteraemia in PWID remains very complex, and an interdisciplinary approach is essential in order to select the best therapy for this vulnerable group of patients.

Modelling the impact of different testing strategies for HCV infection in Switzerland.

OBJECTIVE: Hepatitis C virus (HCV) infection is a major cause of liver disease. Since symptoms of chronic liver disease usually appear only late in the course of the disease, infected individuals may remain undiagnosed until advanced disease has developed. We aimed to investigate which screening strategies would be most effective to detect individuals unaware of their infection. METHODS: We developed a mathematical model for HCV disease progression and compared the current practice of HCV testing in Switzerland with the following screening strategies: intensive screening of active injection drug users (IDU), screening of former IDU, screening of individuals originating from countries with high HCV prevalence, screening of individuals born 1951-1985 (birth-cohort) and universal screening. All screening interventions were considered in addition to a baseline scenario that reflected the current practice of HCV testing. RESULTS: Within the first 4 years (2018-2021), every year, on average 650 cases were diagnosed in the baseline scenario, 660 with intensified IDU screening, 760 with former IDU screening, 830 with origin-based screening, 1420 with birth-cohort screening and 1940 with universal screening. No difference in liver-related mortality and incidence of end-stage liver disease between the screening scenarios was observed. CONCLUSION: Our results suggest that only large-scale screening of the general population could substantially accelerate the rate of HCV diagnosis and treatment in Switzerland and other countries with similar epidemics. However, this implies screening of a large population with low prevalence, and may trigger considerable numbers of false-positive and borderline test results.

Bone mineral density and its determinants in men with opioid dependence.

Data on the influence of opioid substitution therapy (OST) on skeletal health in men is limited. This cross-sectional study aimed to determine the prevalence of low bone mass in male drug users and to evaluate the relationship between endogenous testosterone and bone mass. We recruited 144 men on long-term opioid maintenance therapy followed in the Center of Addiction Medicine in Basel, Switzerland. Data on medical and drug history, fracture risk and history of falls were collected. Bone mineral density (BMD) was evaluated by densitometry and serum was collected for measurements of gonadal hormones and bone markers. 35 healthy age- and BMI-matched men served as the control group. The study participants received OST with methadone (69 %), morphine (25 %) or buprenorphine (6 %). Overall, 74.3 % of men had low bone mass, with comparable bone mass irrespective of OST type. In older men (≥40 years, n = 106), 29.2 % of individuals were osteoporotic (mean T-score -3.0 ± 0.4 SD) and 48.1 % were diagnosed with osteopenia (mean T-score -1.7 ± 0.4 SD). In younger men (n = 38), 65.8 % of men had low bone mass. In all age groups, BMD was significantly lower than in age-and BMI-matched controls. In multivariate analyses, serum free testosterone (fT) was significantly associated with low BMD at the lumbar spine (p = 0.02), but not at the hip. When analysed by quartiles of fT, lumbar spine BMD decreased progressively with decreasing testosterone levels. We conclude that low bone mass is highly prevalent in middle-aged men on long-term opioid dependency, a finding which may partly be determined by partial androgen deficiency.