High prevalence of anti-HCV antibodies in two metropolitan emergency departments in Germany : a prospective screening analysis of 28,809 patients

Background and Aims: The prevalence of hepatitis C virus (HCV) antibodies in Germany has been estimated to be in the range of 0.4–0.63%. Screening for HCV is recommended in patients with elevated ALT levels or significant risk factors for HCV transmission only. However, 15–30% of patients report no risk factors and ALT levels can be normal in up to 20–30% of patients with chronic HCV infection. The aim of this study was to assess the HCV seroprevalence in patients visiting two tertiary care emergency departments in Berlin and Frankfurt, respectively. Methods: Between May 2008 and March 2010, a total of 28,809 consecutive patients were screened for the presence of anti-HCV antibodies. Anti-HCV positive sera were subsequently tested for HCV-RNA. Results: The overall HCV seroprevalence was 2.6% (95% CI: 2.4–2.8; 2.4% in Berlin and 3.5% in Frankfurt). HCV-RNA was detectable in 68% of anti-HCV positive cases. Thus, the prevalence of chronic HCV infection in the overall study population was 1.6% (95% CI 1.5–1.8). The most commonly reported risk factor was former/current injection drug use (IDU; 31.2%) and those with IDU as the main risk factor were significantly younger than patients without IDU (p<0.001) and the male-to-female ratio was 72% (121 vs. 46 patients; p<0.001). Finally, 18.8% of contacted HCV-RNA positive patients had not been diagnosed previously. Conclusions: The HCV seroprevalence was more than four times higher compared to current estimates and almost one fifth of contacted HCV-RNA positive patients had not been diagnosed previously

Investigations on mechanical stability of laser machined optical fibre tips for medical application

Light delivery is a challenging task, when it comes to medical applications. The light is guided through optical fibers from the light source towards the treatment region. In case of interstitial light application, the light has to be decoupled from the fibre and spread to the surrounding tissue. To reach larger tissue volumes, this can be either obtained by adding a scattering volume to the tip of the fibre, or by directly modifying the optical fibre itself in order to break the total reflection within the fibre core. Such modifications can be either on the fibre surface itself or internally in the fibre core. One approach to obtain the fibre structuring could be laser induced surface roughening using an ultrafast laser source. While using volume scattering as diffusor at the fibre tip is currently the gold standard for non-thermal applications (< 0.3W/cm), the decoupling of high power laser intensities for thermal treatment options is still challenging. Structuring the fibre core itself usually is related with a loss of mechanical stability. As fibre breakage and potential loss within the human body can have serious consequences, the mechanical stability is one of the quality criterion in diffuser manufacturing. Therefore, investigations about the mechanical stability of laser manufactured optical fibre diffusers are needed. In order to evaluate the mechanical stability, a 4-point as well as a 2-point breaking test were developed. Different fibre diffusers, based on volume or surface scattering, were manufactured using fs-laser ablation techniques and its breaking strengths were investigated. It could be shown that for surface fibre modifications, the mechanical stability reduces with increasing defect depth. The stability significantly drops when the laser ablation was performed in the thermal energy range. Volume scattering modified fibres only showed a slight reduction in stability compared to un-machined fibres. In conclusion, internal fibre modification seems to be the most promising method to establish optical fibre diffusers, which are capable of several watts of emission power, while preserving its mechanical strength

Drone Security and the Mysterious Case of DJI's DroneID

Consumer drones enable high-class aerial video photography, promise to reform the logistics industry, and are already used for humanitarian rescue operations and during armed conflicts. Contrasting their widespread adoption and high popularity, the low entry barrier for air mobility - a traditionally heavily regulated sector - poses many risks to safety, security, and privacy. Malicious parties could, for example, (mis-)use drones for surveillance, transportation of illegal goods, or cause economic damage by intruding the closed airspace over airports. To prevent harm, drone manufacturers employ several countermeasures to enforce safe and secure use of drones, e.g., they impose software limits regarding speed and altitude, or use geofencing to implement no-fly zones around airports or prisons. Complementing traditional countermeasures, drones from the market leader DJI implement a protocol called DroneID, which is designed to transmit the position of both the drone and its operator to authorized entities such as law enforcement or operators of critical infrastructures. In this paper, we analyze security and privacy claims for drones, focusing on the leading manufacturer DJI with a market share of 94%. We first systemize the drone attack surface and investigate an attacker capable of eavesdropping on the drone's over-the-air data traffic. Based on reverse engineering of DJI firmware, we design and implement a decoder for DJI's proprietary tracking protocol DroneID using only cheap COTS hardware. We show that the transmitted data is not encrypted, but accessible to anyone, compromising the drone operator's privacy. Second, we conduct a comprehensive analysis of drone security: Using a combination of reverse engineering, a novel fuzzing approach tailored to DJI's communication protocol, and hardware analysis, we uncover several critical flaws in drone firmware that allow attackers to gain elevated privileges on two different DJI drones and their remote control. Such root access paves the way to disable or bypass countermeasures and abuse drones. These vulnerabilities have the potential to be triggered remotely, causing the drone to crash mid-flight

Self-reported risk factors for HCV transmission in the anti-HCV positive population at the Berlin study site.

<p>IVDU, intravenous drug-use.</p><p>Multiple responses were possible. Percentages are given in relation to all anti-HCV positive patients (n = 535).</p

Patient characteristics.

a<p>ULN = upper limit of normal; ^bof 42 HCV-RNA negative patients, 3 were still on antiviral treatment at the time of study inclusion.</p

Distribution of anti-HCV and HCV-RNA status for each of the two study sites alone and all patients combined.

<p>Serum samples for HCV-RNA analysis were available from 685 out of 757 anti-HCV positive patients.</p