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Veröffentlichung A new approach to testing the efficacy of drinking water disinfectants(2018) Frohnert, Anne; Grunert, Andreas; Selinka, Hans-Christoph; Szewzyk, RegineNew disinfection procedures are being developed and proposed for use in drinking-water production. Authorising their use requires an effective test strategy that can simulate conditions in practice. For this purpose, we developed a test rig working in a flow-through mode similar to the disinfection procedures in waterworks, but under tightly defined conditions, including very short contact times. To quantify the influence of DOC, temperature and pH on the efficacy of two standard disinfectants, chlorine and chlorine dioxide, simulated use tests were systematically performed. This test rig enabled quantitative comparison of the reduction of four test organisms, two viruses and two bacteria, in response to disinfection. Chlorine was substantially more effective against Enterococcus faecium than chlorine dioxide whereas the latter was more effective against the bacteriophage MS2, especially at pH values of >7.5 at which chlorine efficacies already decline. Contrary to expectation, bacteria were not generally reduced more quickly than viruses. Overall, the results confirm a high efficacy of chlorine and chlorine dioxide, validating them as standard disinfectants for assessing the efficacy of new disinfectants. Furthermore, these data demonstrate that the test rig is an appropriate tool for testing new disinfectants as well as disinfection procedures.Veröffentlichung Detection and characterization of hepatitis E virus genotype 3 in wastewater and urban surface waters in Germany(2020) Beyer, Sophia; Gnirrs, Regina; Selinka, Hans-Christoph; Szewzyk, RegineIn highly populated areas, environmental surveillance of wastewater and surface waters is a key factor to control the circulation of viruses and risks for public health. Hepatitis E virus (HEV) genotype 3 is considered as an emerging pathogen in industrialized countries. Therefore, this study was carried out to determine the prevalence of HEV in environmental waters in urban and suburban regions in Germany. HEV was monitored in water samples using quantitative RT-PCR (RT-qPCR) and nested RT-PCR without or with virus concentration via polyethylene glycol precipitation or ultracentrifugation. By RT-qPCR, 84-100% of influent samples of wastewater treatment plants were positive for HEV RNA. Genotypes HEV-3c and 3f were identified in wastewater, with HEV-3c being the most prevalent genotype. These data correlate with subtypes identified earlier in patients from the same area. Comparison of wastewater influent and effluent samples revealed a reduction of HEV RNA of about 1 log10 during passage through wastewater treatment plants. In addition, combined sewer overflows (CSOs) after heavy rainfalls were shown to release HEV RNA into surface waters. About 75% of urban river samples taken during these CSO events were positive for HEV RNA by RT-qPCR. In contrast, under normal weather conditions, only around 30% of river samples and 15% of samples from a bathing water located at an urban river were positive for HEV. Median concentrations of HEV RNA of all tested samples at this bathing water were below the limit of detection. Source: https://link.springer.comVeröffentlichung Molecular detection of cosaviruses in a patient with acute flaccid paralysis and in sewage samples in Germany(2021) Schneider, Julia; Engler, Matthias; Hofmann, Jörg; Selinka, Hans-ChristophCosaviruses (CoSV) were first identified in stool samples collected from non-polio acute flaccid paralysis (AFP) cases and their healthy contacts in Pakistan in 2003. The clinical importance of CoSV remains unclear as data on epidemiology are scarce and no routine diagnostic testing is done. In this study, we characterized human CoSV (HCoSV) in a child with non-polio AFP and in sewage samples collected in Berlin, Germany. Using unbiased high-throughput sequencing and specific PCR, we characterized a HCoSV-D in stool samples of a three-year-old child hospitalized in Germany with non-polio AFP and travel history to Pakistan. The shedding pattern and absence of other relevant pathogens suggests that HCoSV-D may have been involved in the genesis of AFP. The HCoSV-RNA concentration was high, with 2.57 * 106 copies per mL fecal/suspension, decreasing in follow-up samples. To investigate the possibility of local circulation of HCoSV, we screened Berlin sewage samples collected between 2013 and 2018. Molecular testing of sewage samples has shown the presence of CoSV in several parts of the world, but until now not in Germany. Of our sewage samples, 54.3 % were positive for CoSV, with up to three viral species identified in samples. Phylogenetically, the German sequences clustered intermixed with sequences obtained globally. Together, these findings emphasize the need for further clinical, epidemiological, environmental, pathogenicity and phylogenetic studies of HCoSV. © 2021 Elsevier B.V.Veröffentlichung Überwachung der Pandemieviren SARS-CoV-2 über Abwasseranalysen(2021) Selinka, Hans-ChristophWie die COVID-19-Pandemie 2019/2020/2021 zeigt, können durch die Globalisierung jederzeit Pathogene, in diesem Fall das neue SARS-Coronavirus-2 (SARS-CoV-2), in Deutschland eingeschleppt und zu einer ernsten Gefahr für die Öffentliche Gesundheit werden. Das SARS-CoV-2 wird hauptsächlich über die Luft durch Tröpfchen und Aerosole sowie durch kontaminierte Oberflächen übertragen. Infizierte Personen scheiden das Virus und Abbauprodukte der Viren aber auch über den Stuhl aus. Mit Hilfe molekularbiologischer Analysen können diese Bestandteile im Abwasser nachgewiesen werden. Abwasseruntersuchungen auf SARS-CoV-2 können daher hilfreiche Informationen über den aktuellen Infektionszustand der Population geben, von der das Abwasser stammt und in Kombination mit der klinischen Diagnostik zur zeitnahen Planung und Umsetzung von Maßnahmen zum Infektionsschutz beitragen. Quelle: UMID : Umwelt und Mensch - Informationsdienst ; Umwelt & Gesundheit, Umweltmedizin, Verbraucherschutz / Boden- und Lufthygiene (Berlin) Institut für Wasser- - 1 (2021), 61Veröffentlichung Pool water disinfection by ozone-bromine treatment: Assessing the disinfectant efficacy and the occurrence and in vitro toxicity of brominated disinfection by-products(2021) El-Athman, Fatima; Junek, Ralf; Kämpfe, Alexander David; Mahringer, Daniel; Selinka, Hans-Christoph; Zehlike, Lisa; Grunert, AndreasPool water is continuously circulated and reused after an extensive treatment including disinfection by chlorination, ozonation or UV treatment. In Germany, these methods are regulated by DIN standard 19643. Recently, the DIN standard has been extended by a new disinfection method using hypobromous acid as disinfectant formed by introducing ozone into water with naturally or artificially high bromide content during water treatment. In this study, we tested the disinfection efficacy of the ozone-bromine treatment in comparison to hypochlorous acid in a flow-through test rig using the bacterial indicator strains Escherichia coli, Enterococcus faecium, Pseudomonas aeruginosa, and Staphylococcus aureus and the viral indicators phage MS2 and phage PRD1. Furthermore, the formation of disinfection by-products and their potential toxic effects were investigated in eight pool water samples using different disinfection methods including the ozone-bromine treatment. Our results show that the efficacy of hypobromous acid, depending on its concentration and the tested organism, is comparable to that of hypochlorous acid. Hypobromous acid was effective against five of six tested indicator organisms. However, using Pseudomonas aeruginosa and drinking water as test water, both tested disinfectants (0.6 mg L-1 as Cl2 hypobromous acid as well as 0.3 mg L-1 as Cl2 hypochlorous acid) did not achieve a reduction of four log10 levels within 30 s, as required by DIN 19643. The formation of brominated disinfection by-products depends primarily on the bromide concentration of the filling water, with the treatment method having a smaller effect. The eight pool water samples did not show critical values in vitro for acute cytotoxicity or genotoxicity in the applied assays. In real pool water samples, the acute toxicological potential was not higher than for conventional disinfection methods. However, for a final assessment of toxicity, all single substance toxicities of known DBPs present in pool water treated by the ozone-bromine treatment have to be analyzed additionally. © 2021 The AuthorsVeröffentlichung Lüftungskonzepte in Schulen zur Prävention einer Übertragung hochinfektiöser Viren (SARS-CoV-2) über Aerosole in der Raumluft(2021) Birmili, Wolfram; Daniels, Anja; Moriske, Heinz-Jörn; Selinka, Hans-Christoph; Straff, WolfgangAller Kenntnis nach spielen die mit der Atmung ausgeschiedenen Aerosolpartikel eine wichtige Rolle bei der Verbreitung des 2019 erstmalig aufgetretenen Coronavirus SARS-CoV-2, insbesondere im Rahmen menschlicher Zusammenkünfte in Innenräumen. Diese Arbeit fasst die für den Schulbetrieb relevanten Sachverhalte und Maßnahmen zur Verminderung von Infektionen über den Aerosolpfad zusammen. Eine wichtige Maßnahme ist die Verstärkung der Raumlüftung, d. h. der Austausch möglicherweise kontaminierter Innenraumluft mit Außenluft. Neben der Verminderung der Konzentration infektiöser Aerosole ist Lüftung unabdingbar zur Abfuhr des in Klassenräumen erzeugten Kohlendioxids, der Luftfeuchte und anderer chemischer Stoffe in der Innenraumluft. Unabhängig von Lüftung erweist sich das Tragen von Mund-Nasen-Masken (medizinische Masken bzw. filtrierende Halbmasken) als wirksame Maßnahme. Eine für virushaltige Partikel wirksame Luftreinigung durch feste bzw. mobile Anlagen kann die genannten Maßnahmen unterstützen bzw. in Fällen aushelfen, wenn Räume trotz schlechter Lüftungsmöglichkeit genutzt werden müssen. Der Artikel gibt den Stand des Wissens im Oktober 2021 über verschiedene technische Schutzmaßnahmen wieder, die sich seit Beginn der Pandemie als sinnvoll erwiesen haben, wobei der Fokus auf der Reduzierung von indirekten Infektionen liegt. Neu hinzukommende Varianten von SARS-CoV-2, der Fortschritt der Impfkampagne bei Kindern und Jugendlichen sowie die Zunahme der allgemeinen Immunität werden möglicherweise eine Neubewertung der Maßnahmen erfordern. Neben kurzfristigen und schnell wirksamen Maßnahmen zum Infektionsschutz erscheint es auch geboten, die in Deutschland existierenden Defizite bei Raum- und Gebäudelüftung an Schulen durch eine langfristige Strategie zu beheben. Im Sinne einer dauerhaften Verbesserung der Innenraumluft und der Prävention gegen künftige luftübertragene Infektionskrankheiten erscheint die zunehmende Ausstattung von Schulen mit fest installierten Lüftungsanlagen bzw. raumlufttechnischen Anlagen - mit Option auf Wärme- und Feuchterückgewinnung - als nachhaltige gesellschaftliche Investition. © AutorenVeröffentlichung Picorna-like viruses of the Havel River, Germany(2022) Zell, Roland; Groth, Marco; Selinka, Hans-Christoph; Selinka, LukasTo improve the understanding of the virome diversity of riverine ecosystems in metropolitan areas, a metagenome analysis was performed with water collected in June 2018 from the river Havel in Berlin, Germany. After enrichment of virus particles and RNA extraction, paired-end Illumina sequencing was conducted and assignment to virus groups and families was performed. This paper focuses on picorna-like viruses, the most diverse and abundant group of viruses with impact on human, animal, and environmental health. Here, we describe altogether 166 viral sequences ranging in size from 1 to 11.5†kb. The 71 almost complete genomes are comprised of one candidate iflavirus, one picornavirus, two polycipiviruses, 27 marnaviruses, 27 dicistro-like viruses, and 13 untypeable viruses. Many partial picorna-like virus sequences up to 10.2†kb were also investigated. The sequences of the Havel picorna-like viruses represent genomes of seven of eight so far known Picornavirales families. Detection of numerous distantly related dicistroviruses suggests the existence of additional, yet unexplored virus groups with dicistronic genomes, including few viruses with unusual genome layout. Of special interest is a clade of dicistronic viruses with capsid protein-encoding sequences at the 5'-end of the genome. Also, monocistronic viruses with similarity of their polymerase and capsid proteins to those of dicistroviruses are interesting. A second protein with NTP-binding site present in the polyprotein of solinviviruses and related viruses needs further attention. The results underline the importance to study the viromes of fluvial ecosystems. So far acknowledged marnaviruses have been isolated from marine organisms. However, the present study and available sequence data suggest that rivers and limnic habitats are relevant ecosystems with circulation of marnaviruses as well as a plethora of unknown picorna-like viruses. © 2022 Zell, Groth, Selinka and SelinkaVeröffentlichung Exploring surface water as a transmission medium of avian influenza viruses - systematic infection studies in mallards(2022) Ahrens, Ann Kathrin; Mettenleiter, Thomas C.; Selinka, Hans-ChristophMallards (Anas platyrhynchos) are an abundant anseriform migratory wild bird species worldwide and an important reservoir for the maintenance of low pathogenicity (LP) avian influenza viruses (AIV). They have also been implicated in the spread of high pathogenicity (HP) AIV after spill-over events from HPAIV-infected poultry. The spread of HPAIV within wild water bird populations may lead to viral contamination of natural habitats. The role of small shallow water bodies as a transmission medium of AIV among mallards is investigated here in three experimental settings. (i) Delayed onset but rapid progression of infection seeded by two mallards inoculated with either LP or HP AIV to each eight sentinel mallards was observed in groups with access to a small 100 L water pool. In contrast, groups with a bell drinker as the sole source of drinking water showed a rapid onset but lengthened course of infection. (ii) HPAIV infection also set off when virus was dispersed in the water pool; titres as low as 102 TCID50 L-1 (translating to 0.1 TCID50 mL-1) proved to be sufficient. (iii) Substantial loads of viral RNA (and infectivity) were also found on the surface of the birds' breast plumage. "Unloading" of virus infectivity from contaminated plumage into water bodies may be an efficient mechanism of virus spread by infected mallards. However, transposure of HPAIV via the plumage of an uninfected mallard failed. We conclude, surface water in small shallow water bodies may play an important role as a mediator of AIV infection of aquatic wild birds. © 2022 The Author(s)Veröffentlichung Management kurzzeitiger Verschmutzungen an Flussbadegewässern(2022) Schmidt, Alexandra; Seis, Wolfgang; Selinka, Hans-ChristophFlüsse sind komplexe ökologische Systeme, die eine unterschiedliche Nutzung erfahren. Einerseits bilden sie den Lebensraum vieler Tier- und Pflanzenarten, andererseits gehören sie zu den wichtigsten ökonomischen und infrastrukturellen Einheiten. An Fließgewässer werden somit unterschiedliche Nutzungsansprüche gestellt - mit entsprechenden Auswirkungen. Badegewässer an Flüssen einzurichten und zu managen, stellt daher in mehrfacher Hinsicht eine Herausforderung dar. Strömungen und die Schifffahrt bergen physische Risiken für das Baden im Fluss. Zudem müssen Vorsorgemaßnahmen ergriffen werden, um die Gesundheit der Badenden auch bei einer stark schwankenden hygienischen Wasserqualität zu schützen. Die daraus resultierenden Bemühungen, um ein sicheres Baden in Fließgewässern zu gewährleisten, können sich aber insbesondere für Städte und Metropolregionen lohnen, in denen Seen und Talsperren kaum vorhanden sind oder sich diese nur mit erhöhtem Aufwand für die Bevölkerung erreichen lassen. Vor diesem Hintergrund entstand aus dem BMBFgeförderten Projekt FLUSSHYGIENE (2017-020) nicht nur ein unterstützender thematischer Leitfaden, sondern es konnte im Zuge dessen auch ein Frühwarnsystem an fünf Berliner Flussbadegewässern erfolgreich eingerichtet und betrieben werden. Quelle: UMID : Umwelt und Mensch - Informationsdienst ; Umwelt & Gesundheit, Umweltmedizin, Verbraucherschutz / Boden- und Lufthygiene (Berlin) Institut für Wasser- - (2022), Heft 02, Seite 33Veröffentlichung Hepeliviruses in two waterbodies in Berlin, Germany(2022) Zell, Roland; Groth, Marco; Selinka, Hans-Christoph; Selinka, LukasThe order Hepelivirales comprises RNA viruses of four families (Alphatetraviridae, Benyviridae, Hepeviridae, and Matonaviridae). Sequencing of virus genomes from water samples from the Havel River and the Teltow Canal (Teltowkanal) in Berlin, Germany, revealed 25 almost complete and 68 partial genomes of viruses presumably belonging to the order Hepelivirales. Only one of these viruses exhibited a relationship to a known member of this order. The members of one virus clade have a polymerase with a permuted order of the conserved palm subdomain motifs resembling the polymerases of permutotetraviruses and birnaviruses. Overall, our study further demonstrates the diversity of hepeliviruses and indicates the enzootic prevalence of hepeliviruses in unknown hosts. © 2023 Springer Nature Switzerland AG