Virushepatitis B und D im Jahr 2021

Hepatitis B ist eine der häufigsten Infektionskrankheiten weltweit und im Fall eines chronischen Verlaufs eine der bedeutendsten Ursachen von Leberzirrhose und Leberzellkarzinom. Auch Hepatitis D kommt weltweit vor. Deutschland hat sich den Eliminierungszielen viraler Hepatitiden der WHO bis 2030 verschrieben, allerdings stellte die COVID-19-Pandemie eine große Herausforderung beim Erreichen dieser Ziele dar. Im Jahr 2021 wurde eine Zunahme von übermittelten Hepatitis-B-Fällen um 22 % im Vergleich zu 2020 verzeichnet und damit nach einem wohl hauptsächlich pandemiebedingten Rückgang das Niveau von 2019 nahezu wieder erreicht. Anlässlich des Welt-Hepatitis-Tages werden im Epidemiologischen Bulletin 30/2022 die Meldedaten zu Hepatitis B und D des Jahres 2021 nach Infektionsschutzgesetz dargestellt sowie aktuelle Studien zur Hepatitis-B-Virus-Prävalenz und Impfabdeckung in der Allgemeinbevölkerung und in ausgewählten Subpopulationen zusammengefasst

Reproducibility of methods required to identify and characterize nanoforms of substances

•Nanoforms (NFs) of a substance may be distinguished from one another through differences in their physicochemical properties. When registering nanoforms of a substance for assessment under the EU REACH framework, five basic descriptors are required for their identification: composition, surface chemistry, size, specific surface area and shape. To make the risk assessment of similar NFs efficient, a number of grouping frameworks have been proposed, which often require assessment of similarity on individual physicochemical properties as part of the group justification. Similarity assessment requires an understanding of the achievable accuracy of the available methods. It must be demonstrated that measured differences between NFs are greater than the achievable accuracy of the method, to have confidence that the measured differences are indeed real. To estimate the achievable accuracy of a method, we assess the reproducibility of six analytical techniques routinely used to measure these five basic descriptors of nanoforms: inductively coupled plasma mass spectrometry (ICP-MS), Thermogravimetric analysis (TGA), Electrophoretic light scattering (ELS), Brunauer–Emmett–Teller (BET) specific surface area and transmission and scanning electron microscopy (TEM and SEM). Assessment was performed on representative test materials to evaluate the reproducibility of methods on single NFs of substances. The achievable accuracy was defined as the relative standard deviation of reproducibility (RSDR) for each method. •Well established methods such as ICP-MS quantification of metal impurities, BET measurements of specific surface area, TEM and SEM for size and shape and ELS for surface potential and isoelectric point, all performed well, with low RSDR, generally between 5 and 20%, with maximal fold differences usually <1.5 fold between laboratories. Applications of technologies such as TGA for measuring water content and putative organic impurities, additives or surface treatments (through loss on ignition), which have a lower technology readiness level, demonstrated poorer reproducibility, but still within 5-fold differences. The expected achievable accuracy of ICP-MS may be estimated for untested analytes using established relationships between concentration and reproducibility, but this is not yet the case for TGA measurements of loss on ignition or water content. The results here demonstrate an approach to estimate the achievable accuracy of a method that should be employed when interpreting differences between NFs on individual physicochemical properties

Risk factors associated with loss to follow-up from tuberculosis treatment in Tajikistan: A case-control study

markdownabstract_Background:_ There are very few studies on reasons for loss to follow-up from TB treatment in Central Asia. This study assessed risk factors for LTFU and compared their occurrence with successfully treated (ST) patients in Tajikistan. _Methods:_ This study took place in all TB facilities in the 19 districts with at least 5 TB patients registered as loss to follow-up (LTFU) from treatment. With a matched case control design we included all LTFU patients registered in the selected districts in 2011 and 2012 as cases, with ST patients from the same districts being controls. Data were copied from patient records and registers. Conditional logistic regressions were run to analyse associations between collected variables and LTFU as dependent variable. _Results:_ Three hundred cases were compared to 592 controls. Half of the cases had migrated or moved. In multivariate analysis, risk factors associated with increased LTFU were migration to another country, moving within country, having side effects of treatment and being previously treated for TB. Medical staff also mentioned patient refusal, stigma and family problems as risk factors. _Conclusions:_ LTFU of TB patients in Tajikistan is largely a result of migration, and to a lesser extent associated with side-effects and previous treatment. There is a need to strengthen referral between health facilities within Tajikistan and with neighbouring countries and support patients with side effects and/or previous TB to prevent loss to follow-up from treatment

Airborne engineered nanomaterials in the workplace: a review of release and worker exposure during nanomaterial production and handling processes

For exposure and risk assessment in occupational settings involving engineered nanomaterials (ENMs), it is important to understand the mechanisms of release and how they are influenced by the ENM, the matrix material, and process characteristics. This review summarizes studies providing ENM release information in occupational settings, during different industrial activities and using various nanomaterials. It also assesses the contextual information - such as the amounts of materials handled, protective measures, and measurement strategies - to understand which release scenarios can result in exposure. High-energy processes such as synthesis, spraying, and machining were associated with the release of large numbers of predominantly small-sized particles. Low-energy processes, including laboratory handling, cleaning, and industrial bagging activities, usually resulted in slight or moderate releases of relatively large agglomerates. The present analysis suggests that process-based release potential can be ranked, thus helping to prioritize release assessments, which is useful for tiered exposure assessment approaches and for guiding the implementation of workplace safety strategies. The contextual information provided in the literature was often insufficient to directly link release to exposure. The studies that did allow an analysis suggested that significant worker exposure might mainly occur when engineering safeguards and personal protection strategies were not carried out as recommended