Publications by authors named "Boris Klempa"

is a family for negative-sense RNA viruses with genomes of about 10.5-14.6 kb.

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The viral genome of the SARS-CoV-2 coronavirus, the aetiologic agent of COVID-19, encodes structural, non-structural, and accessory proteins. Most of these components undergo rapid genetic variations, though to a lesser extent the essential viral proteases. Consequently, the protease and/or deubiquitinase activities of the cysteine proteases M and PL became attractive targets for the design of antiviral agents.

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  • In April 2023, the International Committee on Taxonomy of Viruses (ICTV) approved changes to the phylum's classification during their annual vote.
  • The update included the addition of one new family, 14 new genera, and 140 new species.
  • Additionally, the taxonomy featured the renaming of two genera and 538 species, along with the removal of one species and the abolition of four others.
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The official classification of newly discovered or long-known unassigned viruses by the International Committee on Taxonomy of Viruses (ICTV) requires the deposition of coding-complete or -near-complete virus genome sequences in GenBank to fulfill a requirement of the taxonomic proposal (TaxoProp) process. However, this requirement is fairly new; thus, genomic sequence information is fragmented or absent for many already-classified viruses. As a result, taxon-wide modern phylogenetic analyses are often challenging, if not impossible.

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Sensitive and rapid point-of-care assays have been crucial in the global response to SARS-CoV-2. Loop-mediated isothermal amplification (LAMP) has emerged as an important diagnostic tool given its simplicity and minimal equipment requirements, although limitations exist regarding sensitivity and the methods used to detect reaction products. We describe the development of Vivid COVID-19 LAMP, which leverages a metallochromic detection system utilizing zinc ions and a zinc sensor, 5-Br-PAPS, to circumvent the limitations of classic detection systems dependent on pH indicators or magnesium chelators.

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  • Viral infections from families such as Zika and Dengue pose significant challenges for diagnosis and tracking due to their short duration in the blood, vague symptoms, and laboratory cross-reactivity.
  • In Central Europe, West Nile, Usutu, and tick-borne encephalitis viruses are the main endemic flaviviruses, causing serious neurological diseases and complicating blood and organ safety during transplants.
  • The rise in co-circulation of these viruses highlights the inadequacy of current diagnostic methods, leading experts to advocate for the urgent adoption of advanced techniques like next-generation sequencing and urine screening in clinical practices.
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Even with the widespread uptake of vaccines, the SARS-CoV-2-induced COVID-19 pandemic continues to overwhelm many healthcare systems worldwide. Consequently, massive scale molecular diagnostic testing remains a key strategy to control the ongoing pandemic, and the need for instrument-free, economic and easy-to-use molecular diagnostic alternatives to PCR remains a goal of many healthcare providers, including WHO. We developed a test (Repvit) based on gold nanoparticles that can detect SARS-CoV-2 RNA directly from nasopharyngeal swab or saliva samples with a limit of detection (LOD) of 2.

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The tick-borne encephalitis virus (TBEV) causes a most important viral life-threatening illness transmitted by ticks. The interactions between the virus and ticks are largely unexplored, indicating a lack of experimental tools and systematic studies. One such tool is recombinant reporter TBEV, offering antibody-free visualization to facilitate studies of transmission and interactions between a tick vector and a virus.

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The coronavirus transforms the cytoplasm of susceptible cells to support virus replication. It also activates autophagy-like processes, the role of which is not well understood. Here, we studied SARS-CoV-2-infected Vero E6 cells using transmission electron microscopy and autophagy PCR array.

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Background: The genomes of SARS-CoV-2 are classified into variants, some of which are monitored as variants of concern (e.g. the Delta variant B.

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  • * It was expanded to include two new families, 41 new genera, and 98 new species, along with reclassifications for 349 species.
  • * The article details the updated taxonomy of Negarnaviricota, including corrections of misspelled names for seven species.
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  • A novel hantavirus called Kiwira virus was detected in Angolan free-tailed bats in Tanzania and the Democratic Republic of Congo, indicating its presence in wildlife across two African countries.
  • The virus showed the highest RNA levels in the bats' spleens, and genetic sequencing revealed it is closely related to other bat-infecting hantaviruses.
  • The findings suggest that Kiwira virus is actively replicating in bats, which could pose a risk for potential transmission to humans, especially since these bats often roost near human habitats.
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The outbreak of the coronavirus disease 2019 (COVID-19) raises questions about the effective inactivation of its causative agent, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in medical wastewater by disinfectants. For this reason, our study of wastewater from a selected hospital evaluated several different advanced oxidation methods (Fenton reaction and Fenton-like reaction and ferrate (VI)) capable of effectively removing SARS-CoV-2 RNA. The obtained results of all investigated oxidation processes, such as ferrates, Fenton reaction and its modifications achieved above 90% efficiency in degradation of SARS-CoV-2 RNA in model water.

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Sensitive and accurate RT-qPCR tests are the primary diagnostic tools to identify SARS-CoV-2-infected patients. While many SARS-CoV-2 RT-qPCR tests are available, there are significant differences in test sensitivity, workflow (e.g.

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Tick-borne encephalitis virus (TBEV) causes serious the neurological disease, tick-borne encephalitis (TBE). TBEV can be transmitted to humans by ticks as well as by the alimentary route, which is mediated through the consumption of raw milk products from infected ruminants such as sheep, goats, and cows. The alimentary route of TBEV was recognized in the early 1950s and many important experimental studies were performed shortly thereafter.

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Cross-sectional seroprevalence study of SARS-CoV-2 IgG antibodies was accomplished in the Slovak Academy of Sciences to inform authorities of research institutions about the situation at their workplaces, to assess the risk of next exposure to SARS-CoV-2, and to guide decisions on institutional measures sustaining essential research in evolving epidemic situation. Study participants provided informed consent, anamnestic information, and self-collected dry blood spot samples that were analyzed by ELISA for SARS-CoV-2 S protein-specific IgG antibodies. Relative antibody levels detected in 1928 subjects showed seroprevalence of 84.

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Background: Invasive mosquitoes of the genus Aedes are quickly spreading around the world. The presence of these alien species is concerning for both their impact on the native biodiversity and their high vector competence. The surveillance of Aedes invasive mosquito (AIM) species is one of the most important steps in vector-borne disease control and prevention.

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Surveillance of the SARS-CoV-2 variants including the quickly spreading mutants by rapid and near real-time sequencing of the viral genome provides an important tool for effective health policy decision making in the ongoing COVID-19 pandemic. Here we evaluated PCR-tiling of short (~400-bp) and long (~2 and ~2.5-kb) amplicons combined with nanopore sequencing on a MinION device for analysis of the SARS-CoV-2 genome sequences.

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Article Synopsis
  • - In March 2021, the ICTV updated the phylum Negarnaviricota by officially ratifying new taxonomy changes.
  • - The revision included the addition of four families, three subfamilies, 42 genera, and 200 species, along with several renaming and abolishing of species.
  • - This article outlines the newly accepted taxonomic structure of Negarnaviricota following the ICTV's decisions.
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SARS-CoV-2 mutants carrying the ∆H69/∆V70 deletion in the amino-terminal domain of the Spike protein emerged independently in at least six lineages of the virus (namely, B.1.1.

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  • - This study discusses a great grey owl in a zoo in Slovakia that died from a West Nile virus infection, highlighting its significance in understanding the virus in Central Europe.
  • - Genetic analysis of the viral strain showed it is more closely related to WNV strains from Hungary, Greece, and Bulgaria, and it has a specific mutation linked to increased neurovirulence.
  • - Additional tests on other captive owls indicated local transmission of WNV, suggesting an ongoing presence of the virus in the area despite no WNV-positive mosquitoes being found.
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In the fight against the recent COVID-19 pandemics, testing is crucial. Nasopharyngeal swabs and real-time RT-PCR are used for the detection of the viral RNA. The collection of saliva is non-invasive, pain-free and does not require trained personnel.

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