Denevérek által hordozott vírusok evolúciós kapcsolatainak vizsgálata európai denevérfajokban

A denevérek rendje (Chiroptera) jelenleg több mint 1250 fajt számlál, amely a bolygón élő emlősök körübelül 20%-át jelenti. Rendkívül széles földrajzi elterjedésüknek köszönhetően az Antarktisz kivételével minden kontinensről ismertek, olyan különleges biológiai adaptációkkal rendelkeznek, mint például az echolokáció vagy a repülés. Filogenetikai vizsgálataikból igen alapos irodalmi háttér áll rendelkezésre, amely jelenlegi ismereteink szerint a korai Eocénba teszi első megjelenésüket (50-52 millió évvel ezelőtt). Tekintettel viszonylag hosszú evolúciós múltjukra és a szárazföldi emlősök között egyedülálló repülési képességükre, rendkívül jelentős fajgazdagságra és földrajzi elterjedésre tettek szert. Egyelőre tudományos szempontból kevéssé magyarázott az a képességük, miszerint tünetmentes hordozói számos magas patogenitású kórokozónak. Hosszú evolúciós múltjuk és rendkívül változatos diverzifikációjuk számos koevolúciós folyamatot is eredményezett a velük kapcsolatban álló élőlényekkel, köztük ektoparazitákkal vagy vírusokkal is. A virális zoonózisok állatokról emberre terjedő vírusokat jelentenek. A zoonózisok jelentős hányada vadállatokról kerül a humán populációra. Érdekes módon az ilyen fertőzési események gyakrabban történnek meg vadállatok-emberek, mint háziállatok-emberek között. Az elmúlt évtizedben a denevérek egyre gyakrabban jelentették egy-egy humán populációban kitört járvány forrásait. Markáns példa a 2002-2003-as SARS (Severe Acute Respiratory Syndrome) coronavírus világjárvány, vagy a jelenleg is tartó MERS (Middle Eastern Respiratory Syndrome) coronavírus járvány az Arab-félszigeten. A 2014-es nyugat-afrikai ebolavirus járvány legvalószínűbb forrásaként is a denevéreket tartják számon. A WHO által számontartott, emberiségre legveszélyesebb kórokozók közül is több denevérekhez köthető (Nipahvirus, Hendravirus, Filovírusok stb). A globalizációs folyamatok (kereskedelem, turizmus stb.) és az emberiség folyamatos térnyerése egyre több denevér-ember kontakt eseményre ad lehetőséget, amely tekintettel az ismertetett tényekre komoly közegészségügyi kockázatot jelent a felbukkanó virális zoonózisok tekintetében. Az elmúlt évtizedekben felbukkant két magas patogenitású coronavirus (SARS, MERS) megjelenése az emberi populációban is ezeknek a folyamatoknak volt köszönhető

The importance of equally accessible genomic surveillance in the age of pandemics

Genomic epidemiology is now a core component in investigating the spread of a disease during an outbreak and for future preparedness to tackle emerging zoonoses. During the last decades, several viral diseases arose and emphasized the importance of molecular epidemiology in tracking the dispersal route, supporting proper mitigation measures, and appropriate vaccine development. In this perspective article, we summarized what has been done so far in the genomic epidemiology field and what should be considered in the future. We traced back the methods and protocols employed over time for zoonotic disease response. Either to small outbreaks such as the severe acute respiratory syndrome (SARS) outbreak identified first in 2002 in Guangdong, China, or to a global pandemic like the one that we are experiencing now since 2019 when the severe acute respiratory syndrome 2 (SARS-CoV-2) virus emerged in Wuhan, China, following several pneumonia cases, and subsequently spread worldwide. We explored both the benefits and shortages encountered when relying on genomic epidemiology, and we clearly present the disadvantages of inequity in accessing these tools around the world, especially in countries with less developed economies. For effectively addressing future pandemics, it is crucial to work for better sequencing equity around the globe. © 2023, The Author(s)

Nursing homes and the elderly regarding the COVID-19 pandemic: situation report from Hungary

The global impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is significant in terms of public health effects and its long-term socio-economic implications. Among all social groups, the elderly is by far the most affected age group regarding morbidity and mortality. In multiple countries spanning several continents, there are an increasing number of reports referencing the novel coronavirus disease-2019 (COVID-19) spread among nursing homes. These areas are now recognized as potent hotspots regarding the pandemic, which one considers with special regard. Herein, we present currently available data of fatal COVID-19 cases throughout Hungary, along with the analysis of the co-morbidity network. We also report on viral genomic data originating from a nursing home resident. The genomic data was used for viral haplotype network analysis. We emphasize the urgent need for public health authorities to focus on nursing homes and residential service units worldwide, especially in the care of the elderly and infirmed. Our results further emphasize the recent statement released by the World Health Organization (WHO) regarding the vulnerability among seniors and especially the high risk of COVID-19 emergence throughout nursing and social homes

Single-particle detection of native SARS-CoV-2 virions by microfluidic resistive pulse sensing

Microfluidic resistive pulse sensing (MRPS) was used to determine the size –distribution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on detecting nearly 30,000 single virions. However, the ultrastructure of SARS-CoV-2 is thoroughly described, but ensemble properties of SARS-CoV-2, e.g., its particle size distribution, are sparsely reported. According to the MRPS results, the size distribution of SARS-CoV-2 follows a log-normal function with a mean value of 85.1 nm, which corresponds to an approximate diameter of the viral envelope. This result also confirms the low number (< 50) of spike proteins on the surface of the virions

Genetic characterization of a novel picornavirus in Algerian bats: co-evolution analysis of bat-related picornaviruses

Bats are reservoirs of numerous zoonotic viruses. The Picornaviridae family comprises important pathogens which may infect both humans and animals. In this study, a bat-related picornavirus was detected from Algerian Minioptreus schreibersii bats for the first time in the country. Molecular analyses revealed the new virus originates to the Mischivirus genus. In the operational use of the acquired sequence and all available data regarding bat picornaviruses, we performed a co-evolutionary analysis of mischiviruses and their hosts, to authentically reveal evolutionary patterns within this genus. Based on this analysis, we enlarged the dataset, and examined the co-evolutionary history of all bat-related picornaviruses including their hosts, to effectively compile all possible species jumping events during their evolution. Furthermore, we explored the phylogeny association with geographical location, host-genus and host-species in both data sets

A Single Early Introduction Governed Viral Diversity in the Second Wave of SARS-CoV-2 Epidemic in Hungary

Retrospective evaluation of past waves of the SARS-CoV-2 epidemic is key for designing optimal interventions against future waves and novel pandemics. Here we report on analysing genome sequences of SARS-CoV-2 from the first two waves of the epidemic in 2020 in Hungary, mirroring a suppression and a mitigation strategy, respectively. Our analysis reveals that the two waves markedly differed in viral diversity and transmission patterns. Specifically, unlike in several European areas or in the USA, we have found no evidence for early introduction and cryptic transmission of the virus in the first wave of the pandemic in Hungary. Despite the introduction of multiple viral lineages, extensive community spread was prevented by a timely national lockdown in March 2020. In sharp contrast, the majority of the cases in the much larger second wave can be linked to a single transmission lineage of the pan-European B.1.160 variant. This lineage was introduced unexpectedly early, followed by a two-month-long cryptic transmission before a soar of detected cases in September 2020. Epidemic analysis has revealed that the dominance of this lineage in the second wave was not associated with an intrinsic transmission advantage. This finding is further supported by the rapid replacement of B.1.160 by the alpha variant (B.1.1.7) that launched the third wave of the epidemic in February 2021. Overall, these results illustrate how the founder effect in combination with cryptic transmission, instead of repeated international introductions or higher transmissibility, can govern viral diversity

Retrospective Detection and Complete Genomic Sequencing of Canine morbillivirus in Eurasian Otter (Lutra lutra) Using Nanopore Technology

The Eurasian otter (Lutra lutra) is a piscivorous apex predator in aquatic habitats, and a flagship species of conservation biology throughout Europe. Despite the wide distribution and ecological relevance of the species, there is a considerable lack of knowledge regarding its virological and veterinary health context, especially in Central Europe. Canine morbillivirus (Canine distemper virus (CDV)) is a highly contagious viral agent of the family Paramyxoviridae with high epizootic potential and veterinary health impact. CDV is present worldwide among a wide range of animals; wild carnivores are at particular risk. As part of a retrospective study, lung-tissue samples (n = 339) from Eurasian otters were collected between 2000 and 2021 throughout Hungary. The samples were screened for CDV using a real-time RT-PCR method. Two specimens proved positive for CDV RNA. In one sample, the complete viral genome was sequenced using a novel, pan-genotype CDV-specific amplicon-based sequencing method with Oxford Nanopore sequencing technology. Both viral sequences were grouped to a European lineage based on the hemagglutinin-gene phylogenetic classification. In this article, we present the feasibility of road-killed animal samples for understanding the long-term dynamics of CDV among wildlife and provide novel virological sequence data to better understand CDV circulation and evolution

Before the Pandemic Ends: Making Sure This Never Happens Again

Introduction On 30 January 2020, the World Health Organization (WHO) declared a Global Health Emergency of international concern attendant to the emergence and spread of SARS-CoV-2, nearly two months after the first reported emergence of human cases in Wuhan, China. In the subsequent two months, global, national and local health personnel and infrastructures have been overwhelmed, leading to suffering and death for infected people, and the threat of socio-economic instability and potential collapse for humanity as a whole. This shows that our current and traditional mode of coping, anchored in responses after the fact, is not capable of dealing with the crisis of emerging infectious disease. Given all of our technological expertise, why is there an emerging disease crisis, and why are we losing the battle to contain and diminish emerging diseases? Part of the reason is that the prevailing paradigm explaining the biology of pathogen-host associations (coevolution, evolutionary arms races) has assumed that pathogens must evolve new capacities - special mutations – in order to colonize new hosts and produce emergent disease (e.g. Parrish and Kawaoka, 2005). In this erroneous but broadly prevalent view, the evolution of new capacities creates new opportunities for pathogens. Further, given that mutations are both rare and undirected, the highly specialized nature of pathogen-host relationships should produce an evolutionary firewall limiting dissemination; by those definitions, emergences should be rare (for a historical review see Brooks et al., 2019). Pathogens, however, have become far better at finding us than our traditional understanding predicts. We face considerable risk space for pathogens and disease that directly threaten us, our crops and livestock – through expanding interfaces bringing pathogens and hosts into increasing proximity, exacerbated by environmental disruption and urban density, fueled by globalized trade and travel. We need a new paradigm that explains what we are seeing. Additional section headers: The Stockholm Paradigm The DAMA Protocol A Sense of Urgency and Long-Term Commitment Reference