Major decline of hepatitis C virus incidence rate over two decades in a cohort of drug users

Injecting drug users (DU) are at high risk for hepatitis C virus (HCV) and HIV infections. To examine the prevalence and incidence of these infections over a 20-year period (1985–005), the authors evaluated 1276 DU from the Amsterdam Cohort Studies who had been tested prospectively for HIV infection and retrospectively for HCV infection. To compare HCV and HIV incidences, a smooth trend was assumed for both curves over calendar time. Risk factors for HCV seroconversion were determined using Poisson regression. Among ever-injecting DU, the prevalence of HCV antibodies was 84.5% at study entry, and 30.9% were co-infected with HIV. Their yearly HCV incidence dropped from 27.5/100 person years (PY) in the 1980s to 2/100 PY in recent years. In multivariate analyses, ever-injecting DU who currently injected and borrowed needles were at increased risk of HCV seroconversion (incidence rate ratio 29.9, 95% CI 12.6, 70.9) compared to ever-injecting DU who did not currently inject. The risk of HCV seroconversion decreased over calendar time. The HCV incidence in ever-injecting DU was on average 4.4 times the HIV incidence, a pattern seen over the entire study period. The simultaneous decline of both HCV and HIV incidence probably results from reduced risk behavior at the population level

Opportunistische screening op genitale infecties met Chlamydia trachomatis onder de seksueel actieve bevolking van Amsterdam IV:Kosteneffectiviteitsanalyse van screening uitgebreid met het oog op de specifieke dynamiek van een infectieziekte

Objective. To estimate cost effectiveness of opportunistic screening for Chlamydia trachomatis (CT) in sexually active persons in general practices in Amsterdam, the Netherlands. Design. Pharmacoeconomic model calculation. Method. In addition to the risk of CT infection and associated complications (such as ectopic pregnancy and infertility) and the costs of screening and CT complications, epidemiological data on the spread of CT was also included in the model calculation. On the basis of this calculation, an estimate was made of the net direct and indirect costs of screening for an avoided serious complication associated with CT infection. Results. Screening women in the age group 15-34 years was estimated to save costs compared with no screening. Adding men to a screening directed at women only would not save costs. Net costs were then estimated at approximately € 1000- € 3000 per avoided serious complication, depending on the specific age group considered. The net costs of screening would be higher if the CT prevalence prior to screening was lower, if the screening period was shorter and if the rate of identified partners was lower. The costs would be less if the test costs were less and if there was a higher risk of complications. Conclusion. From a pharmacoeconomic point of view a CT-screening programme for sexually active women in Amsterdam can be recommended