Chronic hepatitis B and C infections in the Netherlands: estimated prevalence in risk groups and the general population.

Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are usually asymptomatic for decades, thus targeted screening can prevent liver disease by timely diagnosis and linkage to care. More robust estimates of chronic HBV and HCV infections in the general population and risk groups are needed. Using a modified workbook method, the total number of ever chronically infected individuals in the Netherlands in 2016 was determined using population size and prevalence estimates from studies in the general and high-risk population. The estimated 2016 chronic HBV infection prevalence is 0.34% (low 0.22%, high 0.47%), corresponding to approximately 49 000 (low 31 000, high 66 000) HBV-infected individuals aged 15 years and older. The estimated ever-chronic HCV infection prevalence is 0.16% (low 0.06%, high 0.27%), corresponding to approximately 23 000 (low 8000, high 38 000) ever-chronic HCV-infected individuals. The prevalence of chronic HBV and HCV infections in the Netherlands is low. First-generation migrants account for most infections with 81% and 60% of chronic HBV and HCV infections, respectively. However, about one-fifth of HCV infections is found in the general population at low risk. This method can serve as an example for countries in need of more accurate prevalence estimates, to help the design and evaluation of prevention and control policies.

Hepatitis C: The beginning of the end-key elements for successful European and national strategies to eliminate HCV in Europe.

Hepatitis C virus (HCV) infection is a major public health problem in the European Union (EU). An estimated 5.6 million Europeans are chronically infected with a wide range of variation in prevalence across European Union countries. Although HCV continues to spread as a largely "silent pandemic," its elimination is made possible through the availability of the new antiviral drugs and the implementation of prevention practices. On 17 February 2016, the Hepatitis B & C Public Policy Association held the first EU HCV Policy Summit in Brussels. This summit was an historic event as it was the first high-level conference focusing on the elimination of HCV at the European Union level. The meeting brought together the main stakeholders in the field of HCV: clinicians, patient advocacy groups, representatives of key institutions and regional bodies from across European Union; it served as a platform for one of the most significant disease elimination campaigns in Europe and culminated in the presentation of the HCV Elimination Manifesto, calling for the elimination of HCV in Europe by 2030. The launch of the Elimination Manifesto provides a starting point for action in order to make HCV and its elimination in Europe an explicit public health priority, to ensure that patients, civil society groups and other relevant stakeholders will be directly involved in developing and implementing HCV elimination strategies, to pay particular attention to the links between hepatitis C and social marginalization and to introduce a European Hepatitis Awareness Week.

HIV testing week 2015: lowering barriers for HIV testing among high-risk groups in Amsterdam.

BACKGROUND: Evaluation of the HIV Testing Week (HTW) 2015 in Amsterdam: the number of (positive) tested persons, characteristics and testing history of the tested population, the differences in attendance per location and the healthcare workers' experiences and opinions concerning the HTW. METHODS: The HTW took place from 28 November till 4 December 2015. Anonymous HIV rapid testing (INSTI™ HIV1/HIV2 Ab test or Determine™ HIV-1/2 Ag/Ab test) was offered free of charge at four hospitals, 12 general practitioner (GP) clinics, a sexually transmitted infections (STI) clinic, a laboratory, sites of a community-based organisation, and at outreach locations. Home-based testing (OraQuick® In-Home HIV Test) was offered online. The focus was to motivate two groups to test: men who have sex with men (MSM) and non-Western migrants. Questionnaires regarding participant's characteristics and HIV testing history were collected. Also healthcare workers were asked to complete a questionnaire evaluating the HTW. RESULTS: In total, 1231 participants were tested. With three positive HIV tests, the detection rate was 0.3% (95%CI 0.26-0.37). Of all participants, 24.7% (304/1231) were MSM. Respectively, 22.3% (275/1231) and 15.7% (193/1231) were first- and second-generation migrants from a non-Western country. Altogether, 56.7% (698/1231) of participants belonged to one of the targeted risk groups. For 32.7% (402/1231) of participants, it was the first time they received testing, and 35.1% (432/1231) were tested more than 1 year ago. Among MSM 13.2% were tested for the first time, among first- and second-generation non-Western migrants this percentage was significantly higher at 27.2% and 33.5% respectively (p < 0.01). The number of tested participants per location varied widely, especially between GP clinics (range 3-63). Healthcare workers were positive about the HTW: about half (46.2%) stated they would more readily offer an HIV test following their experience with the HTW. CONCLUSIONS: This was the first time the Amsterdam HTW was organised on such a large scale. The majority of the tested population belonged to one of the targeted risk groups and received testing either for the first time or for the first time in over a year. It is important to further build upon the experiences of the HTW and offer free of charge low-threshold HIV testing more structurally. An evaluation of cost-effectiveness is also warranted for future editions of the HTW.

Evaluation of a risk assessment questionnaire to assist hepatitis C screening in the general population.

Many individuals with hepatitis C virus (HCV) infection are undiagnosed. This study evaluates a risk assessment questionnaire, developed for use online to target blood-screening for HCV. Two hundred and eighty-nine patients with known HCV status completed a written questionnaire on prominent HCV risk factors. Questionnaires generated advice to seek testing if at least one risk factor was reported. Agreement of the testing advice with the HCV status of respondents was evaluated. Subsequently, we validated our questionnaire among 985 patients of an outpatient clinic for sexually transmitted infections. The post-test-probability-of-disease (PTPD) and diagnostic gain (PTPD minus prior probability of disease) were calculated. The questionnaire's sensitivity and specificity were 84.6% and 63.8%, respectively, and higher in the STI clinic patients. The PTPD of positive testing advice was 72.5% given HCV prevalence of 53.0%, yielding a diagnostic gain of 19.5%. Applying the estimated prevalence in the general Dutch population (0.1-0.4%), and the anticipated prevalence in the online project (1.0-6.0%), yielded diagnostic gains of 0.13-0.53% and 1.3-7.0%, respectively. We conclude that our questionnaire succeeded in selecting at-risk individuals as its testing advice agreed well with the HCV status. We suggest that the questionnaire be used online as a selection tool for HCV blood-screening in the general population.

Never injected, but hepatitis C virus-infected: a study among self-declared never-injecting drug users from the Amsterdam Cohort Studies.

The aim of this study was to gain insight in transmission routes of hepatitis C virus (HCV) infection among never-injecting drug users (DU) by studying, incidence, prevalence, determinants and molecular epidemiology of HCV infection. From the Amsterdam Cohort Studies among DU, 352 never-injecting DU were longitudinally tested for HCV antibodies. Logistic regression was used to identify factors associated with antibody prevalence. Part of HCV NS5B was sequenced to determine HCV genotype and for phylogenetic analyses, in which sequences were compared with those from injecting DU. HCV antibody prevalence was 6.3% and HCV incidence was 0.49/1000 PY. HIV-positive status, female sex and starting injection drug use during follow-up (a putative marker of past injection drug use), were independently associated with HCV prevalence. The main genotypes found were genotype 3a (50%) and 1a (30%). Phylogenetic analysis revealed that HCV strains in never-injecting DU did not cluster together and did not differ from HCV strains circulating in injecting DU. We found a higher HCV prevalence in never-injecting DU than in the general population. Phylogenetic analysis shows a strong link with the injecting DU population. The increased risk could be related to underreporting of injecting drug use or to household or sexual transmission from injectors to noninjectors. Our findings stress the need for HCV testing of DU who report never injecting, especially given the potential to treat HCV infection effectively.

Hepatitis E virus seroprevalence and determinants in various study populations in the Netherlands.

BACKGROUND: The epidemiology of hepatitis E virus (HEV) is not fully understood. In this study, we assessed putative risk factors for HEV seropositivity in various study populations in the Netherlands. METHODS: Data and samples from five different study populations were analysed: (A) blood donors (n = 5,239), (B) adults reporting a vegetarian life style since the age of 12 years (n = 231), (C) residents of Amsterdam, the Netherlands, with different ethnic backgrounds (n = 1,198), (D) men who have sex with men (MSM) (HIV positive and HIV negative) (n = 197), and (E) persons who use drugs (PWUD) (HIV positive and HIV negative) (n = 200). Anti-HEV immunoglobulin M (IgM) and immunoglobulin G (IgG) testing was performed using ELISA test (Wantai). RESULTS: HEV IgM seroprevalence was low across all study populations (<1% to 8%). The age and gender-adjusted HEV IgG seroprevalence was 24% among blood donors (reference group) and 9% among the vegetarian group (adjusted Relative Risk [aRR]:0.36, 95%CI:0.23-0.57). Among participants of different ethnic backgrounds, the adjusted HEV IgG seroprevalence was 16% among participants with a Dutch origin (aRR:0.64, 95%CI:0.40-1.02), 2% among South-Asian Surinamese (aRR:0.07, 95%CI:0.02-0.29), 3% among African Surinamese (aRR:0.11, 95%CI:0.04-0.34), 34% among Ghanaian (aRR:1.53, 95%CI:1.15-2.03), 19% among Moroccan (aRR:0.75, 95%CI:0.49-1.14), and 5% among Turkish (aRR:0.18, 95%CI:0.08-0.44) origin participants. First generation Moroccans had a higher risk for being IgG HEV seropositive compared to second generation Moroccan migrants. The statistical power to perform these analyses in the other ethnic groups was too low. In the MSM group the IgG HEV seroprevalence was 24% (aRR:0.99, 95%CI:0.76-1.29), and among PWUD it was 28% (aRR:1.19, 95%CI:0.90-1.58). The number of sexual partners in the preceding six months was not significantly associated with IgG HEV seropositivity in MSM. The association between HIV status and HEV seropositivity was significant in PWUD, yet absent in MSM. HIV viral load and CD4 cell count were not associated with HEV seropositivity in HIV positive MSM and PWUD. CONCLUSIONS: Vegetarians were significantly less often HEV seropositive. Ethnic origin influenced the risk for being IgG HEV seropositive. MSM and PWUD were not at higher risk for being IgG HEV seropositive than blood donors.

[Hepatitis C in the Netherlands: sparse data on the current prevalence and the necessity for epidemiological studies and innovative methods for detecting infected individuals]. / Hepatitis C in Nederland: schaarse gegevens over actuele prevalentie en de noodzaak van epidemiologisch onderzoek en innovatieve opsporingsmethoden.

Hepatitis C is a blood-borne virus infection with an estimated 180 million infected individuals worldwide. Hepatitis C virus (HCV) infection may lead to liver failure and cancer of the liver. In 2004, in view of the improved treatment options, the Dutch Health Council again recommended that the groups at risk of HCV infection should be tracked down and informed, and that epidemiological studies should be conducted. Currently, there are few data on the prevalence of HCV infection in the Netherlands. HCV risk groups are (former) injecting drug users, haemodialysis patients and haemophiliacs, people treated with blood or blood products before 1992, people who have undergone certain invasive or medical procedures with insufficiently sterilised instruments, household contacts and partners of HCV-infected individuals and children born to HCV-infected mothers. Insight into the epidemiology of HCV infection in the Netherlands is necessary so that reliable estimates of the magnitude of hepatitis C as a public health problem can be made. Several projects for the detection of HCV infected individuals and epidemiological studies have started in 2007.

The estimated future disease burden of hepatitis C virus in the Netherlands with different treatment paradigms.

BACKGROUND & AIMS: Prevalence of hepatitis C virus (HCV) infection in the Netherlands is low (anti-HCV prevalence 0.22%). All-oral treatment with direct-acting antivirals (DAAs) is tolerable and effective but expensive. Our analysis projected the future HCV-related disease burden in the Netherlands by applying different treatment scenarios. METHODS: Using a modelling approach, the size of the HCV-viraemic population in the Netherlands in 2014 was estimated using available data and expert consensus. The base scenario (based on the current Dutch situation) and different treatment scenarios (with increased efficacy, treatment uptake, and diagnoses) were modelled and the future HCV disease burden was predicted for each scenario. RESULTS: The estimated number of individuals with viraemic HCV infection in the Netherlands in 2014 was 19,200 (prevalence 0.12%). By 2030, this number is projected to decrease by 4 5% in the base scenario and by 85% if the number of treated patients increases. Furthermore, the number of individuals with hepatocellular carcinoma and liver-related deaths is estimated to decrease by 19% and 27%, respectively, in the base scenario, but may both be further decreased by 68% when focusing on treatment of HCV patients with a fibrosis stage of ≥ F2. CONCLUSIONS: A substantial reduction in HCV-related disease burden is possible with increases in treatment uptake as the efficacy of current therapies is high. Further reduction of HCV-related disease burden may be achieved through increases in diagnosis and preventative measures. These results might inform the further development of effective disease management strategies in the Netherlands.