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1.
Zootaxa ; 4821(1): zootaxa.4821.1.4, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33056332

RESUMO

The family Cycloposthiidae include 69 species, distributed in 17 genera, all of them described in symbiotic association with various mammalian host species. The taxonomic classification of the family is confused because of its broad diagnosis and absence of synapomorphies. To validate taxa and eliminate synonyms, the present work performed a brief taxonomic review of Cycloposthiidae, compiling morphological characterization, host records, and geographic location data. According to our review, the family should be instead, composed of 13 genera and 66 species; it was observed that the currently in use taxonomic characters do not reflect evolutionary divergence; and that the broad host range of Cycloposthiidae may be linked to cortex characteristics of these organisms or because of the fact that they do not constitute a monophyletic group. Thus, the performance of more molecular phylogenetic studies, including more cycloposthiid representatives and as well as the use of recent morphological techniques would be necessary to clarify the taxonomy of the group.


Assuntos
Cilióforos , Animais , Evolução Biológica , Especificidade de Hospedeiro , Filogenia
2.
Zootaxa ; 4768(2): zootaxa.4768.2.11, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33056531

RESUMO

Hygrobates salamandrarum Goldschmidt, Gerecke and Alberti, 2002 (Acari, Hydrachnidia, Hygrobatidae) is the first-known water mite parasitizing adult newts. After its description, three further species of newt-parasitizing mites were described and the subgenus Lurchibates Goldschmidt and Fu, 2011 was proposed for the group, now containing four newt-parasitizing mites. Until now, each water mite species parasitizes a different newt species (Table 1), suggesting possible mite-newt co-speciation. In order to test this hypothesis, we need an accurate taxonomy of both of the hosts and parasites. However, the taxonomy of those Asian newt genera known to be parasitized by Lurchibates mites has been substantially revised after the initial description of the H. salamandrarum. To account for these taxonomic changes, we here revise the host-parasite species list and amend the host species name as shown in Table 1.


Assuntos
Ácaros , Urodelos , Animais , Especificidade de Hospedeiro , Salamandridae , Água
3.
Nat Commun ; 11(1): 4620, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934242

RESUMO

Metagenomic techniques have enabled genome sequencing of unknown viruses without isolation in cell culture, but information on the virus host is often lacking, preventing viral characterisation. High-throughput methods capable of identifying virus hosts based on genomic data alone would aid evaluation of their medical or biological relevance. Here, we address this by linking metagenomic discovery of three virus families in human stool samples with determination of probable hosts. Recombination between viruses provides evidence of a shared host, in which genetic exchange occurs. We utilise networks of viral recombination to delimit virus-host clusters, which are then anchored to specific hosts using (1) statistical association to a host organism in clinical samples, (2) endogenous viral elements in host genomes, and (3) evidence of host small RNA responses to these elements. This analysis suggests two CRESS virus families (Naryaviridae and Nenyaviridae) infect Entamoeba parasites, while a third (Vilyaviridae) infects Giardia duodenalis. The trio supplements five CRESS virus families already known to infect eukaryotes, extending the CRESS virus host range to protozoa. Phylogenetic analysis implies CRESS viruses infecting multicellular life have evolved independently on at least three occasions.


Assuntos
Entamoeba/virologia , Giardia/virologia , Adulto , Estudos de Coortes , Fezes/parasitologia , Fezes/virologia , Feminino , Genoma Viral , Especificidade de Hospedeiro , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Fenômenos Fisiológicos Virais , Vírus/classificação , Vírus/genética , Adulto Jovem
4.
Biomolecules ; 10(9)2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933047

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing a pandemic of coronavirus disease 2019 (COVID-19). The worldwide transmission of COVID-19 from human to human is spreading like wildfire, affecting almost every country in the world. In the past 100 years, the globe did not face a microbial pandemic similar in scale to COVID-19. Taken together, both previous outbreaks of other members of the coronavirus family (severe acute respiratory syndrome (SARS-CoV) and middle east respiratory syndrome (MERS-CoV)) did not produce even 1% of the global harm already inflicted by COVID-19. There are also four other CoVs capable of infecting humans (HCoVs), which circulate continuously in the human population, but their phenotypes are generally mild, and these HCoVs received relatively little attention. These dramatic differences between infection with HCoVs, SARS-CoV, MERS-CoV, and SARS-CoV-2 raise many questions, such as: Why is COVID-19 transmitted so quickly? Is it due to some specific features of the viral structure? Are there some specific human (host) factors? Are there some environmental factors? The aim of this review is to collect and concisely summarize the possible and logical answers to these questions.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/transmissão , Coronavirus/patogenicidade , Pandemias , Pneumonia Viral/transmissão , Fatores Etários , Animais , Betacoronavirus/genética , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/fisiopatologia , Surtos de Doenças , Reservatórios de Doenças/virologia , Feminino , Saúde Global , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Humanos , Masculino , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Especificidade de Órgãos , Peptídeo Hidrolases/fisiologia , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Receptores Virais/fisiologia , Fatores de Risco , Vírus da SARS/patogenicidade , Síndrome Respiratória Aguda Grave/epidemiologia , Proteínas Virais/fisiologia , Tropismo Viral , Virulência , Internalização do Vírus
5.
PLoS Pathog ; 16(9): e1008758, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881980

RESUMO

The COVID-19 pandemic highlights the substantial public health, economic, and societal consequences of virus spillover from a wildlife reservoir. Widespread human transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also presents a new set of challenges when considering viral spillover from people to naïve wildlife and other animal populations. The establishment of new wildlife reservoirs for SARS-CoV-2 would further complicate public health control measures and could lead to wildlife health and conservation impacts. Given the likely bat origin of SARS-CoV-2 and related beta-coronaviruses (ß-CoVs), free-ranging bats are a key group of concern for spillover from humans back to wildlife. Here, we review the diversity and natural host range of ß-CoVs in bats and examine the risk of humans inadvertently infecting free-ranging bats with SARS-CoV-2. Our review of the global distribution and host range of ß-CoV evolutionary lineages suggests that 40+ species of temperate-zone North American bats could be immunologically naïve and susceptible to infection by SARS-CoV-2. We highlight an urgent need to proactively connect the wellbeing of human and wildlife health during the current pandemic and to implement new tools to continue wildlife research while avoiding potentially severe health and conservation impacts of SARS-CoV-2 "spilling back" into free-ranging bat populations.


Assuntos
Animais Selvagens/virologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Animais , Quirópteros/virologia , Genoma Viral/genética , Especificidade de Hospedeiro/fisiologia , Humanos , Pandemias
6.
Sci Rep ; 10(1): 16007, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994418

RESUMO

Since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a pandemic event in the world, it has not only caused huge economic losses, but also a serious threat to global public health. Many scientific questions about SARS-CoV-2 and Coronavirus disease (COVID-19) were raised and urgently need to be answered, including the susceptibility of animals to SARS-CoV-2 infection. Here we tested whether tree shrew, an emerging experimental animal domesticated from wild animal, is susceptible to SARS-CoV-2 infection. No clinical signs were observed in SARS-CoV-2 inoculated tree shrews during this experiment except the increasing body temperature particularly in female animals. Low levels of virus shedding and replication in tissues occurred in all three age groups. Notably, young tree shrews (6 months to 12 months) showed virus shedding at the earlier stage of infection than adult (2 years to 4 years) and old (5 years to 7 years) animals that had longer duration of virus shedding comparatively. Histopathological examine revealed that pulmonary abnormalities were the main changes but mild although slight lesions were also observed in other tissues. In summary, tree shrew is less susceptible to SARS-CoV-2 infection compared with the reported animal models and may not be a suitable animal for COVID-19 related researches. However, tree shrew may be a potential intermediate host of SARS-CoV-2 as an asymptomatic carrier.


Assuntos
Infecções por Coronavirus/veterinária , Especificidade de Hospedeiro/fisiologia , Pandemias/veterinária , Pneumonia Viral/veterinária , Tupaiidae/virologia , Animais , Betacoronavirus , Infecções por Coronavirus/patologia , Suscetibilidade a Doenças/veterinária , Suscetibilidade a Doenças/virologia , Feminino , Masculino , Pneumonia Viral/patologia , Carga Viral , Eliminação de Partículas Virais/fisiologia
7.
Viruses ; 12(9)2020 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933150

RESUMO

Coronaviruses are enveloped RNA viruses capable of causing respiratory, enteric, or systemic diseases in a variety of mammalian hosts that vary in clinical severity from subclinical to fatal. The host range and tissue tropism are largely determined by the coronaviral spike protein, which initiates cellular infection by promoting fusion of the viral and host cell membranes. Companion animal coronaviruses responsible for causing enteric infection include feline enteric coronavirus, ferret enteric coronavirus, canine enteric coronavirus, equine coronavirus, and alpaca enteric coronavirus, while canine respiratory coronavirus and alpaca respiratory coronavirus result in respiratory infection. Ferret systemic coronavirus and feline infectious peritonitis virus, a mutated feline enteric coronavirus, can lead to lethal immuno-inflammatory systemic disease. Recent human viral pandemics, including severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and most recently, COVID-19, all thought to originate from bat coronaviruses, demonstrate the zoonotic potential of coronaviruses and their potential to have devastating impacts. A better understanding of the coronaviruses of companion animals, their capacity for cross-species transmission, and the sharing of genetic information may facilitate improved prevention and control strategies for future emerging zoonotic coronaviruses. This article reviews the clinical, epidemiologic, virologic, and pathologic characteristics of nine important coronaviruses of companion animals.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus/isolamento & purificação , Animais de Estimação/virologia , Animais , Camelídeos Americanos/virologia , Doenças do Gato/epidemiologia , Doenças do Gato/virologia , Gatos/virologia , Quirópteros/virologia , Coronavirus/classificação , Coronavirus/genética , Coronavirus/fisiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Reservatórios de Doenças/virologia , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães/virologia , Peritonite Infecciosa Felina/epidemiologia , Peritonite Infecciosa Felina/virologia , Furões/virologia , Variação Genética , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Cavalos/virologia , Especificidade de Hospedeiro , Humanos , RNA Viral/genética , Glicoproteína da Espícula de Coronavírus/fisiologia , Replicação Viral , Zoonoses
8.
PLoS One ; 15(8): e0234099, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810132

RESUMO

Two common ecological assumptions are that host generalist and rare species are poorer competitors relative to host specialist and more abundant counterparts. While these assumptions have received considerable study in both plant and animals, how they apply to ectomycorrhizal fungi remains largely unknown. To investigate how interspecific competition may influence the anomalous host associations of the rare ectomycorrhizal generalist fungus, Suillus subaureus, we conducted a seedling bioassay. Pinus strobus seedlings were inoculated in single- or two-species treatments of three Suillus species: S. subaureus, S. americanus, and S. spraguei. After 4 and 8 months of growth, seedlings were harvested and scored for mycorrhizal colonization as well as dry biomass. At both time points, we found a clear competitive hierarchy among the three ectomycorrhizal fungal species: S. americanus > S. subaureus > S. spraguei, with the competitive inferior, S. spraguei, having significantly delayed colonization relative to S. americanus and S. subaureus. In the single-species treatments, we found no significant differences in the dry biomasses of P. strobus seedlings colonized by each Suillus species, suggesting none was a more effective plant symbiont. Taken together, these results indicate that the rarity and anomalous host associations exhibited by S. subaureus in natural settings are not driven by inherently poor competitive ability or host growth promotion, but that the timing of colonization is a key factor determining the outcome of ectomycorrhizal fungal competitive interactions.


Assuntos
Micorrizas/crescimento & desenvolvimento , Pinus/microbiologia , Simbiose/fisiologia , Basidiomycota/classificação , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Biomassa , Interações entre Hospedeiro e Microrganismos/fisiologia , Especificidade de Hospedeiro/genética , Especificidade de Hospedeiro/fisiologia , Pinus/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia
9.
Proc Natl Acad Sci U S A ; 117(36): 22311-22322, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32826334

RESUMO

The novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of COVID-19. The main receptor of SARS-CoV-2, angiotensin I converting enzyme 2 (ACE2), is now undergoing extensive scrutiny to understand the routes of transmission and sensitivity in different species. Here, we utilized a unique dataset of ACE2 sequences from 410 vertebrate species, including 252 mammals, to study the conservation of ACE2 and its potential to be used as a receptor by SARS-CoV-2. We designed a five-category binding score based on the conservation properties of 25 amino acids important for the binding between ACE2 and the SARS-CoV-2 spike protein. Only mammals fell into the medium to very high categories and only catarrhine primates into the very high category, suggesting that they are at high risk for SARS-CoV-2 infection. We employed a protein structural analysis to qualitatively assess whether amino acid changes at variable residues would be likely to disrupt ACE2/SARS-CoV-2 spike protein binding and found the number of predicted unfavorable changes significantly correlated with the binding score. Extending this analysis to human population data, we found only rare (frequency <0.001) variants in 10/25 binding sites. In addition, we found significant signals of selection and accelerated evolution in the ACE2 coding sequence across all mammals, and specific to the bat lineage. Our results, if confirmed by additional experimental data, may lead to the identification of intermediate host species for SARS-CoV-2, guide the selection of animal models of COVID-19, and assist the conservation of animals both in native habitats and in human care.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética , Pneumonia Viral/metabolismo , Aminoácidos , Animais , Betacoronavirus/metabolismo , Sítios de Ligação , Infecções por Coronavirus/virologia , Evolução Molecular , Variação Genética , Especificidade de Hospedeiro , Humanos , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Ligação Proteica , Receptores Virais/química , Receptores Virais/genética , Receptores Virais/metabolismo , Seleção Genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Vertebrados
10.
Nature ; 584(7821): 398-402, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32759999

RESUMO

Land use change-for example, the conversion of natural habitats to agricultural or urban ecosystems-is widely recognized to influence the risk and emergence of zoonotic disease in humans1,2. However, whether such changes in risk are underpinned by predictable ecological changes remains unclear. It has been suggested that habitat disturbance might cause predictable changes in the local diversity and taxonomic composition of potential reservoir hosts, owing to systematic, trait-mediated differences in species resilience to human pressures3,4. Here we analyse 6,801 ecological assemblages and 376 host species worldwide, controlling for research effort, and show that land use has global and systematic effects on local zoonotic host communities. Known wildlife hosts of human-shared pathogens and parasites overall comprise a greater proportion of local species richness (18-72% higher) and total abundance (21-144% higher) in sites under substantial human use (secondary, agricultural and urban ecosystems) compared with nearby undisturbed habitats. The magnitude of this effect varies taxonomically and is strongest for rodent, bat and passerine bird zoonotic host species, which may be one factor that underpins the global importance of these taxa as zoonotic reservoirs. We further show that mammal species that harbour more pathogens overall (either human-shared or non-human-shared) are more likely to occur in human-managed ecosystems, suggesting that these trends may be mediated by ecological or life-history traits that influence both host status and tolerance to human disturbance5,6. Our results suggest that global changes in the mode and the intensity of land use are creating expanding hazardous interfaces between people, livestock and wildlife reservoirs of zoonotic disease.


Assuntos
Biodiversidade , Especificidade de Hospedeiro , Zoonoses/microbiologia , Zoonoses/parasitologia , Zoonoses/virologia , Animais , Aves/microbiologia , Aves/parasitologia , Aves/virologia , Humanos , Mamíferos/microbiologia , Mamíferos/parasitologia , Mamíferos/virologia , Especificidade da Espécie , Zoonoses/transmissão
11.
Viruses ; 12(8)2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32806708

RESUMO

The fatal acute respiratory coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since COVID-19 was declared a pandemic by the World Health Organization in March 2020, infection and mortality rates have been rising steadily worldwide. The lack of a vaccine, as well as preventive and therapeutic strategies, emphasize the need to develop new strategies to mitigate SARS-CoV-2 transmission and pathogenesis. Since mouse hepatitis virus (MHV), severe acute respiratory syndrome coronavirus (SARS-CoV), and SARS-CoV-2 share a common genus, lessons learnt from MHV and SARS-CoV could offer mechanistic insights into SARS-CoV-2. This review provides a comprehensive review of MHV in mice and SARS-CoV-2 in humans, thereby highlighting further translational avenues in the development of innovative strategies in controlling the detrimental course of SARS-CoV-2. Specifically, we have focused on various aspects, including host species, organotropism, transmission, clinical disease, pathogenesis, control and therapy, MHV as a model for SARS-CoV and SARS-CoV-2 as well as mouse models for infection with SARS-CoV and SARS-CoV-2. While MHV in mice and SARS-CoV-2 in humans share various similarities, there are also differences that need to be addressed when studying murine models. Translational approaches, such as humanized mouse models are pivotal in studying the clinical course and pathology observed in COVID-19 patients. Lessons from prior murine studies on coronavirus, coupled with novel murine models could offer new promising avenues for treatment of COVID-19.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Vírus da Hepatite Murina/fisiologia , Pneumonia Viral/virologia , Animais , Betacoronavirus/genética , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Modelos Animais de Doenças , Especificidade de Hospedeiro , Humanos , Camundongos , Vírus da Hepatite Murina/genética , Vírus da Hepatite Murina/patogenicidade , Pandemias , Vírus da SARS/genética , Vírus da SARS/patogenicidade , Vírus da SARS/fisiologia , Internalização do Vírus , Replicação Viral
12.
Med Sci (Paris) ; 36(8-9): 797-802, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32755538

RESUMO

SARS-CoV-2 (severe acute respiratory syndrome-coronavirus-2, which emerged in China at the end of 2019, is responsible for a global health crisis resulting in the confinement of more than 3 billion people worldwide and the sharp decline of the world economy. In this context, a race against the clock is launched in order to develop a treatment to stop the pandemic as soon as possible. A study published in Nature by the Volker Thiel team reports the development of reverse genetics for SARS-CoV-2 allowing them to recreate the virus in just a few weeks. The perspectives of this work are very interesting since it will allow the genetic manipulation of the virus and thus the development of precious tools which will be useful to fight the infection. Even though this approach represents a technological leap that will improve our knowledge of the virus, it also carries the germ of possible misuse and the creation of the virus for malicious purposes. The advantages and disadvantages of recreating SARS-CoV-2 in this pandemic period are discussed in this mini-synthesis.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , Organismos Geneticamente Modificados , Pandemias , Pneumonia Viral/virologia , Genética Reversa/métodos , Betacoronavirus/patogenicidade , Derramamento de Material Biológico , Cromossomos Artificiais de Levedura , Clonagem Molecular/métodos , Coronaviridae/classificação , Coronaviridae/genética , Coronaviridae/patogenicidade , Infecções por Coronavirus/prevenção & controle , DNA Complementar/genética , Especificidade de Hospedeiro , Humanos , Organismos Geneticamente Modificados/genética , Organismos Geneticamente Modificados/patogenicidade , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , RNA Viral/genética , Recombinação Genética , Risco , Vacinas Virais
13.
Med Sci (Paris) ; 36(8-9): 783-796, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32773024

RESUMO

SARS-CoV-2 is a new human coronavirus (CoV), which emerged in People's Republic of China at the end of 2019 and is responsible for the global Covid-19 pandemic that caused more than 540 000 deaths in six months. Understanding the origin of this virus is an important issue and it is necessary to determine the mechanisms of its dissemination in order to be able to contain new epidemics. Based on phylogenetic inferences, sequence analysis and structure-function relationships of coronavirus proteins, informed by the knowledge currently available, we discuss the different scenarios evoked to account for the origin - natural or synthetic - of the virus. On the basis of currently available data, it is impossible to determine whether SARS-CoV-2 is the result of a natural zoonotic emergence or an accidental escape from experimental strains. Regardless of its origin, the study of the evolution of the molecular mechanisms involved in the emergence of this pandemic virus is essential to develop therapeutic and vaccine strategies.


Assuntos
Betacoronavirus/genética , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/virologia , Coronavirus/classificação , Evolução Molecular , Pandemias , Filogenia , Pneumonia Viral/virologia , RNA Viral/genética , Sequência de Aminoácidos , Animais , Betacoronavirus/classificação , Betacoronavirus/isolamento & purificação , Derramamento de Material Biológico , China/epidemiologia , Infecções por Coronaviridae/transmissão , Infecções por Coronaviridae/veterinária , Infecções por Coronaviridae/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Reservatórios de Doenças , Mutação com Ganho de Função , Genoma Viral , HIV/genética , Especificidade de Hospedeiro , Humanos , Mamíferos/virologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Vírus Reordenados/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/fisiologia , Zoonoses
14.
BMC Res Notes ; 13(1): 398, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854762

RESUMO

OBJECTIVE: In December 2019 a novel coronavirus (SARS-CoV-2) that is causing the current COVID-19 pandemic was identified in Wuhan, China. Many questions have been raised about its origin and adaptation to humans. In the present work we performed a genetic analysis of the Spike glycoprotein (S) of SARS-CoV-2 and other related coronaviruses (CoVs) isolated from different hosts in order to trace the evolutionary history of this protein and the adaptation of SARS-CoV-2 to humans. RESULTS: Based on the sequence analysis of the S gene, we suggest that the origin of SARS-CoV-2 is the result of recombination events between bat and pangolin CoVs. The hybrid SARS-CoV-2 ancestor jumped to humans and has been maintained by natural selection. Although the S protein of RaTG13 bat CoV has a high nucleotide identity with the S protein of SARS-CoV-2, the phylogenetic tree and the haplotype network suggest a non-direct parental relationship between these CoVs. Moreover, it is likely that the basic function of the receptor-binding domain (RBD) of S protein was acquired by the SARS-CoV-2 from the MP789 pangolin CoV by recombination and it has been highly conserved.


Assuntos
Betacoronavirus/genética , Coronaviridae/genética , Recombinação Genética , Glicoproteína da Espícula de Coronavírus/genética , Adaptação Biológica/genética , Animais , Sítios de Ligação/genética , Quirópteros/virologia , Eutérios/virologia , Evolução Molecular , Furina/metabolismo , Especificidade de Hospedeiro , Humanos , Peptidil Dipeptidase A/metabolismo , Filogenia , Seleção Genética , Glicoproteína da Espícula de Coronavírus/metabolismo
15.
PLoS One ; 15(8): e0237780, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32845922

RESUMO

Modeling the behavior of zoonotic pandemic threats is a key component of their control. Many emerging zoonoses, such as SARS, Nipah, and Hendra, mutated from their wild type while circulating in an intermediate host population, usually a domestic species, to become more transmissible among humans, and this transmission route will only become more likely as agriculture and trade intensifies around the world. Passage through an intermediate host enables many otherwise rare diseases to become better adapted to humans, and so understanding this process with accurate mathematical models is necessary to prevent epidemics of emerging zoonoses, guide policy interventions in public health, and predict the behavior of an epidemic. In this paper, we account for a zoonotic disease mutating in an intermediate host by introducing a new mathematical model for disease transmission among three species. We present a model of these disease dynamics, including the equilibria of the system and the basic reproductive number of the pathogen, finding that in the presence of biologically realistic interspecies transmission parameters, a zoonotic disease with the capacity to mutate in an intermediate host population can establish itself in humans even if its R0 in humans is less than 1. This result and model can be used to predict the behavior of any zoonosis with an intermediate host and assist efforts to protect public health.


Assuntos
Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Emergentes/epidemiologia , Reservatórios de Doenças/microbiologia , Modelos Biológicos , Zoonoses/epidemiologia , Animais , Animais Domésticos/microbiologia , Animais Selvagens/microbiologia , Bactérias/genética , Bactérias/patogenicidade , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/transmissão , Surtos de Doenças/prevenção & controle , Vetores de Doenças , Especificidade de Hospedeiro/genética , Humanos , Taxa de Mutação , Vírus/genética , Vírus/patogenicidade , Zoonoses/microbiologia , Zoonoses/prevenção & controle , Zoonoses/transmissão
16.
Med Hypotheses ; 143: 110121, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32759006

RESUMO

SARS-CoV-2 incidence and mortality in Europe have shown wide variation. Northern Italy in particular the Lombardy region, north-eastern French regions, Switzerland and Belgium were amongst the hardest hit, while the central and southern Italian regions, all the Balkan countries from Slovenia to Greece and the Islands of Malta and Cyprus had much fewer cases and deaths per capita, and deaths per number of cases. Differences in public health measures, and health care delivery, in the author's opinion, can only partly explain the difference. The geographical distribution of Phlebotomus sand-flies and the relative distribution of arthropod borne diseases Leishmaniasis and Phlebovirus infections especially the Sicilian Sandfly fever group corresponds to most areas of low prevalence of SARS-CoV-2. A hypothesis is proposed whereby repeated arthropod or sandfly vector infection of humans by novel viruses of zoonotic origins carrying bat or mammalian RNA/DNA, such as phleboviruses may have resulted in the development of an effective evolutionary immune response to most novel zoonotic viruses such as SARS-CoV-2 by means of survival of the fittest possibly over many generations. This process probably ran in parallel and concurrent with the progressive evolution of novel coronaviruses which spread from one mammalian species to another. Other possible, but less likely mechanisms for the role of sandfly meals within a much shorter time frame may have led to, (i) previous exposure and infection of humans with the SARS-Cov-2 virus itself, or a closely related corona virus in the previous decades, or (ii) exposure of human populations to parts coronavirus protein namely either S or more likely N protein carried mechanically by arthropods, but without clinical disease causing direct immunity or (iii) by causing infection with other arthropod borne viruses which could carry bat DNA/RNA and have similar functional proteins resulting in an immediate cross-reactive immune response rather than by natural selection. The Evidence possibly supporting or disputing this hypothesis is reviewed, however the major problem with the hypothesis is that to date no coronavirus has ever been isolated from arthropods. Such a hypothesis can only be supported by research investigating the possible biological relationship of arthropods and coronaviruses where paradoxically they may be promoting immunity rather than disease.


Assuntos
Arbovirus/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Imunidade Coletiva , Insetos Vetores/virologia , Pandemias , Phlebotomus/virologia , Pneumonia Viral/imunologia , Animais , Anticorpos Antivirais/análise , Conflitos Armados , Artrópodes/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Reações Cruzadas , Reservatórios de Doenças/virologia , Europa (Continente)/epidemiologia , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Humanos , Incidência , Itália , Mamíferos/virologia , Pneumonia Viral/epidemiologia , Vírus da Febre do Flebótomo Napolitano/imunologia , Seleção Genética , Especificidade da Espécie , Proteínas Virais/imunologia , Zoonoses
17.
Nat Commun ; 11(1): 4018, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782301

RESUMO

The gut microbiome is an ecosystem that involves complex interactions. Currently, our knowledge about the role of the gut microbiome in health and disease relies mainly on differential microbial abundance, and little is known about the role of microbial interactions in the context of human disease. Here, we construct and compare microbial co-abundance networks using 2,379 metagenomes from four human cohorts: an inflammatory bowel disease (IBD) cohort, an obese cohort and two population-based cohorts. We find that the strengths of 38.6% of species co-abundances and 64.3% of pathway co-abundances vary significantly between cohorts, with 113 species and 1,050 pathway co-abundances showing IBD-specific effects and 281 pathway co-abundances showing obesity-specific effects. We can also replicate these IBD microbial co-abundances in longitudinal data from the IBD cohort of the integrative human microbiome (iHMP-IBD) project. Our study identifies several key species and pathways in IBD and obesity and provides evidence that altered microbial abundances in disease can influence their co-abundance relationship, which expands our current knowledge regarding microbial dysbiosis in disease.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Consórcios Microbianos , Obesidade/microbiologia , Adulto , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/metabolismo , Estudos de Coortes , Disbiose/metabolismo , Disbiose/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Especificidade de Hospedeiro , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Obesidade/metabolismo
18.
Arch Virol ; 165(10): 2291-2299, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32754877

RESUMO

The multimammate mouse (Mastomys natalensis; M. natalensis) serves as the main reservoir for the zoonotic arenavirus Lassa virus (LASV), and this has led to considerable investigation into the distribution of LASV and other related arenaviruses in this host species. In contrast to the situation with arenaviruses, the presence of other viruses in M. natalensis remains largely unexplored. In this study, herpesviruses and polyomaviruses were identified and partially characterized by PCR methods, sequencing, and phylogenetic analysis. In tissues sampled from M. natalensis populations in Côte d'Ivoire and Mali, six new DNA viruses (four betaherpesviruses, one gammaherpesvirus and one polyomavirus) were identified. Phylogenetic analysis based on glycoprotein B amino acid sequences showed that the herpesviruses clustered with cytomegaloviruses and rhadinoviruses of multiple rodent species. The complete circular genome of the newly identified polyomavirus was amplified by PCR. Amino acid sequence analysis of the large T antigen or VP1 showed that this virus clustered with a known polyomavirus from a house mouse (species Mus musculus polyomavirus 1). These two polyomaviruses form a clade with other rodent polyomaviruses, and the newly identified virus represents the third known polyomavirus of M. natalensis. This study represents the first identification of herpesviruses and the discovery of a novel polyomavirus in M. natalensis. In contrast to arenaviruses, we anticipate that these newly identified viruses represent a low zoonotic risk due to the normally highly restricted specificity of members of these two DNA virus families to their individual mammalian host species.


Assuntos
Genoma Viral , Infecções por Herpesviridae/epidemiologia , Herpesviridae/genética , Filogenia , Infecções por Polyomavirus/epidemiologia , Polyomavirus/genética , Doenças dos Roedores/epidemiologia , África ao Sul do Saara/epidemiologia , Animais , Antígenos Virais de Tumores/genética , Proteínas do Capsídeo/genética , Reservatórios de Doenças/virologia , Herpesviridae/classificação , Herpesviridae/isolamento & purificação , Infecções por Herpesviridae/virologia , Especificidade de Hospedeiro , Tipagem Molecular , Murinae/virologia , Polyomavirus/classificação , Polyomavirus/isolamento & purificação , Infecções por Polyomavirus/virologia , Doenças dos Roedores/virologia , Proteínas do Envelope Viral/genética
20.
Virus Res ; 288: 198113, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32771430

RESUMO

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is recognized as one of the life-threatening viruses causing the most destructive pandemic in this century. The genesis of this virus is still unknown. To elucidate its molecular evolution and regulation of gene expression, the knowledge of codon usage is a pre-requisite. In this study, an attempt was made to document the genome-wide codon usage profile and the various factors influencing the codon usage patterns of SARS-CoV-2 in human and dog. The SARS-CoV-2 genome showed relative abundance of A and U nucleotides and relative synonymous codon usage analysis revealed that the preferred synonymous codons mostly end with A/U. The analysis of ENc-GC3s, Neutrality and Parity rule 2 plots indicated that natural selection and other undefined factors dominate the overall codon usage bias in SARS-CoV-2 whereas the impact of mutation pressure is comparatively minor. The codon adaptation index and relative codon deoptimization index of SARS-CoV-2 deciphered that human is more favoured host for adaptation compared to dog. These results enhance our understanding of the factors involved in evolution of the novel human SARS-CoV-2 and its adaptability in dog.


Assuntos
Adaptação Biológica/genética , Betacoronavirus/genética , Uso do Códon , Infecções por Coronavirus/virologia , Doenças do Cão/virologia , Genoma Viral , Pneumonia Viral/virologia , Animais , Gatos , Bovinos , Quirópteros , Cães , Evolução Molecular , Cavalos , Especificidade de Hospedeiro , Humanos , Mutação , Pandemias , Seleção Genética , Suínos
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