How long is the long COVID? a retrospective analysis of football players in two major European Championships. (preprint)

Objectives, the goal of this study was to investigate the correlation between SARS-CoV-2 infection and muscle injuries among a large sample of professional soccer players. Methods, A retrospective cohort study was conducted on professional soccer players from the Serie A and LaLiga leagues during the 2019-2020 and 2020-2021 football seasons. The players were divided into two groups based on whether they contracted the Sars-CoV-2 infection (C+) or not (C-) during the 2020/2021 season. Data collection was conducted using the Transfermarkt24 site. Results, In the 2019-2020 both championships showed non-significant differences in the average number of muscular injuries between the C+ group and the C- group (Serie A: p=0.194; 95%CI: -0.044 to 0.215, LaLiga p=0.915; 95%CI: -0.123 to 0.137). In the 2020-2021 the C+ group had a significantly higher number of muscular injuries compared to the C- group in both championships (Serie A: p<0.001; 95%CI 0.731 to 1.038; LaLiga: p<0.001; 95%CI: 0.773 to 1.054). Multiple linear regression analysis confirmed that belonging to C+ in the season 2020/2021 was the variable that most strongly influenced the probability of having a muscle injury in both championships. Survival analysis revealed a hazard ratio of 3.73 (95%CI 3.018 to 4.628) and of 5.14 (95% CI 3.200 to 8.254) for Serie A and LaLiga respectively. Conclusions This retrospective cohort study revealed a significant association between SARS-CoV-2 infection and increased risk of muscle injury, emphasizing the importance of carefully considering the infection in the decision-making process for determining athletes' readiness to return to sport.

Genome-based comparison between the recombinant SARS-CoV-2 XBB and its parental lineages (preprint)

Recombination is the main contributor to RNA virus evolution, and SARS-CoV-2 during the pandemic produced several recombinants. The most recent SARS-CoV-2 recombinant is the lineage labeled XBB, also known as Gryphon, which arose from BJ.1 and BM.1.1.1. Here we performed a genome-based survey aimed to compare the new recombinant with its parental lineages that never became dominant. Genetic analyses indicated that the recombinant XBB and its first descendant XBB.1 show an evolutionary condition typical of an evolutionary blind background with no further epidemiologically relevant descendant. Genetic variability and expansion capabilities are slightly higher than parental lineages. Bayesian Skyline Plot indicates that XBB reached its plateau around October 6, 2022 and after an initial rapid growth the viral population size did not further expand, and around November 10, 2022 its levels of genetic variability decreased. Simultaneously with the reduction of the XBB population size, an increase of the genetic variability of its first sub-lineage XBB.1 occurred, that in turn reached the plateau around November 9, 2022 showing a kind of vicariance with its direct progenitors. Structure analysis indicates that the affinity for ACE2 surface in XBB/XBB.1 RBDs is weaker than for BA.2 RBD. In conclusion, nowadays XBB and XBB.1 do not show evidence about a particular danger or high expansion capability. Genome-based monitoring must continue uninterrupted in order to individuate if further mutations can make XBB more dangerous or generate new subvariants with different expansion capability.

Genetic and structural data on the SARS-CoV-2 Omicron BQ.1 variant reveal its low potential for epidemiological expansion (preprint)

The BQ.1 SARS-CoV-2 variant, also known as Cerberus, is one of the most recent Omicron descendant lineages. Compared to its direct progenitor BA.5, BQ.1 carries out some additional spike mutations in some key antigenic site which confer it further immune escape ability over other circulating lineage. In such a context, here we performed a genome-based survey aimed to obtain an as complete as possible nuance of this rapidly evolving Omicron subvariant. Genetic data suggests that BQ.1 represents an evolutionary blind background, lacking of the rapid diversification which is typical of a dangerous lineage. Indeed, the evolutionary rate of BQ.1 is very similar to that of BA.5 (7.6 x 10-4 and 7 x 10-4 subs/site/year, respectively), which is circulating by several months. Bayesian Skyline Plot reconstruction, indicates low level of genetic variability, suggesting that the peak has been reached around September 3, 2022. Structure analyses performed by comparing the properties of BQ.1 and BA.5 RBD indicated that the impact of the BQ.1 mutations on the affinity for ACE2 may be modest. Likewise, immunoinformatic analyses showed modest differences between the BQ.1 and the BA5 potential B-cells epitope. In conclusion, genetic and structural analysis on SARS-CoV-2 BQ.1 suggest that, it does not show evidence about its particular dangerous or high expansion capability. The monitoring genome-based must continue uninterrupted for a better understanding of its descendant and all other lineages.

Estimating COVID-19-induced Excess Mortality in Lombardy (preprint)

We compare the expected all-cause mortality with the observed one for different age classes during the pandemic in Lombardy, which was the epicenter of the epidemic in Italy and still is the region most affected by the pandemic. A generalized linear mixed model is introduced to model weekly mortality from 2011 to 2019, taking into account seasonal patterns and year-specific trends. Based on the 2019 year-specific conditional best linear unbiased predictions, a significant excess of mortality is estimated in 2020, leading to approximately 35000 more deaths than expected, mainly arising during the first wave. In 2021, instead, the excess mortality is not significantly different from zero, for the 85+ and 15-64 age classes, and significant reductions with respect to the 2020 estimated excess mortality are estimated for other age classes.

Phylogenetic analysis and in silico studies link spike Q675H mutation to SARS-CoV-2 adaptive evolution (preprint)

Genotype screening was implemented in Italy and showed a significant prevalence of new SARS-CoV-2 mutants carrying Q675H mutation, near the furin cleavage site of spike protein. Currently, this mutation, which is expressed on different SARS-CoV-2 lineages circulating worldwide, has not been thoughtfully investigated. Therefore, we performed phylogenetic and biocomputational analysis to better understand SARS-CoV-2 Q675H mutants evolutionary relationships with other circulating lineages and Q675H function in its molecular context. Our studies reveal that Q675H spike mutation is the result of parallel evolution because it arose independently in separate evolutionary clades. In silico data show that the Q675H mutation gives rise to a hydrogen-bonds network in the spike polar region delimiting the conformational space of the highly flexible loop containing the furin cleavage site. This results in an optimized directionality of arginine residues involved in interaction of spike with the furin binding pocket, thus improving proteolytic exposure of the viral protein. Furin was found to have a greater affinity for Q675H than Q675 substrate conformations. As a consequence, Q675H mutation is likely to confer a fitness advantage to SARS-CoV-2 by promoting a more efficient viral entry. Interestingly, here we show an ongoing increase in the occurrence of Q675H spike mutation in the most common SARS-CoV-2 variants of concern (VOC). This finding highlights that, VOC are still evolving and start acquiring the Q675H mutation. At the same time, it suggests that our hypothesis of fitness advantage prompted by Q675H could be concrete.

Cutting epitopes to survive: the case of lambda variant (preprint)

This manuscript concisely reports an in-silico study on the potential impact of the Spike protein mutations on immuno-escape ability of SARS-CoV-2 lambda variant. Biophysical and bioinformatics data suggest that a combination of shortening immunogenic epitope loops and generation of potential N-glycosylation sites may be a viable adaptation strategy potentially allowing this emerging viral variant escaping host immunity.

SARS-CoV-2 B.1.617 Indian variants: are electrostatic potential changes responsible for a higher transmission rate? (preprint)

Lineage B.1.617+, also known as G/452R.V3, is a recently described SARS-CoV-2 variant under investigation (VUI) firstly identified in October 2020 in India. As of May 2021, three sublineages labelled as B.1.617.1, B.1.617.2 and B.1.617.3 have been already identified, and their potential impact on the current pandemic is being studied. This variant has 13 amino acid changes, three in its spike protein, which are currently of particular concern: E484Q, L452R and P681R. Here we report a major effect of the mutations characterizing this lineage, represented by a marked alteration of the surface electrostatic potential (EP) of the Receptor Binding Domain (RBD) of the spike protein. Enhanced RBD-EP is particularly noticeable in the B.1.617.2 sublineage, which shows multiple replacements of neutral or negatively-charged amino acids with positively-charged amino acids. We here hypothesize that this EP change can favor the interaction between the B.1.617+ RBD and the negatively-charged ACE2 thus conferring a potential increase in the virus transmission.

COVID-19 Sniffer Dog experimental training: which protocol and which implications for reliable identification? (preprint)

The introduction of trained sniffer dogs for COVID-19 disease detection could be an opportunity, as previously described for other diseases. Dogs could be trained to detect volatile organic compounds (VOCs), the whiff of COVID-19 disease. Dogs involved in the study were three one male and two females from different breeds, Black German Shepherd, German Shepherd and Dutch Shepherd. The training was performed using sweat samples from COVID-19 positive apteints and from covid-19 free patients admitted at the University Hospital Campus Bio-medico of Rome. Gauze with sweat were collected in glass jar with metal top and put in metal boxes used for dog training. The dog training protocol was performed in two phase: the olfactory conditioning and the olfactory discrimintaion research. The training palnning was focused on the switch moment for the sniffer dog, the moment when the dog was able to identify VOCs specific for COVID-19 disease. At this time the dog was able to identify VOCs specific for COVID-19 disease with significant reliability, in terms of number of correct versus uncorrect (p<0.0001) reporting. In conclusion, this protocol could provide a useful tool for sniffer dogs training and their introduction in mass screening context, cheaper and faster than a conventional testing method.

SARS-CoV-2 shifting transmission dynamics and hidden reservoirs limited the efficacy of public health interventions in Italy (preprint)

We investigated SARS-CoV-2 transmission dynamics in Italy, one of the countries hit hardest by the pandemic, using phylodynamic analysis of viral genetic and epidemiological data. We observed the co-circulation of at least 13 different SARS-CoV-2 lineages over time, which were linked to multiple importations and characterized by large transmission clusters concomitant with a high number of infections. Subsequent implementation of a three-phase nationwide lockdown strategy greatly reduced infection numbers and hospitalizations. Yet we present evidence of sustained viral spread among sporadic clusters acting as "hidden reservoirs" during summer 2020. Mathematical modelling shows that increased mobility among residents eventually catalyzed the coalescence of such clusters, thus driving up the number of infections and initiating a new epidemic wave. Our results suggest that the efficacy of public health interventions is, ultimately, limited by the size and structure of epidemic reservoirs, which may warrant prioritization during vaccine deployment.

SARS-Cov-2 ORF3a: Mutability and Function (preprint)

In this study, the analysis of the changes of SARS-CoV-2 Orf3a protein during pandemic is reported. Orf3a, a conserved protein in the Coronaviruses, is involved in virus replication and release. A software workflow able to carry out a quick, systematic and repeatable screening of the SARS-CoV-2 genome isolates to detect protein mutations, was utilized to scan 70,752 high-quality SARS-CoV-2 genomes available in GISAID databank at the end of August 2020. All ORF3a mutations in the virus genomes were grouped according to the collection date interval and over the entire data set. The considered intervals were start of collection-February, March, April, May, June, July and August 2020. The top five most frequent variants were examined within each collection interval. Overall, seventeen variants have been isolated. Ten of the seventeen mutant sites occur within the transmembrane (TM) domain of ORF3a and are in contact with the central pore or side tunnels. The other variant sites are in different places of the Orf3a structure. Within the entire sample, the five most frequent mutations are V13L, Q57H, Q57H+A99V, G196V and G252V. The same analysis identified 28 sites identically conserved in all the genome isolates. These sites are possibly involved in stabilization of monomer, dimer, tetramerization and interaction with other cellular components. The results here reported can be helpful to understand virus biology and to design new therapeutic strategies.

Emerging of a SARS-CoV-2 viral strain with a deletion in nsp1 (preprint)

Background:The new Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), which was first detected in Wuhan (China) in December of 2019 is responsible for the current global pandemic.Phylogenetic analysis revealed that it is similar to other betacoronaviruses, such as SARS-CoV and Middle-Eastern Respiratory Syndrome, MERS-CoV. Its genome is ∼30 kb in length and contains two large overlapping polyproteins, ORF1a and ORF1ab that encode for several structural and non-structural proteins. The non-structural protein 1 (nsp1) is arguably the most important pathogenic determinant, and previous studies on SARS-CoV indicate that it is both involved in viral replication and hampering the innate immune system response. Detailed experiments of site-specific mutagenesis and in vitro reconstitution studies determined that the mechanisms of action are mediated by i) the presence of specific amino acid residues of nsp1 and b) the interaction between the protein and the host’s small ribosomal unit. In fact, substitution of certain amino acids resulted in reduction of its negative effects.Methods: A total of 17928 genome sequences were obtained from the GISAID database (December 2019 to July 2020) from patients infected by SARS-CoV-2 from different areas around the world. Genomes alignment was performed using MAFFT (REFF) and the nsp1 genomic regions were identified using BioEdit and verified using BLAST. Nsp1 protein of SARS-CoV-2 with and without deletion have been subsequently modelled using I-TASSER.Results: We identified SARS-CoV-2 genome sequences, from several Countries, carrying a previously unknown deletion of 9 nucleotides in position 686-694, corresponding to the AA position 241-243 (KSF). This deletion was found in different geographical areas. Structural prediction modelling suggests an effect on the C-terminal tail structure.Conclusions: Modelling analysis of a newly identified deletion of 3 amino acids (KSF) of SARS-CoV-2 nsp1 suggests that this deletion could affect the structure of the C-terminal region of the protein, important for regulation of viral replication and negative effect on host’s gene expression. In addition, substitution of the two amino acids (KS) from nsp1 of SARS-CoV was previously reported to revert loss of interferon-alpha expression. The deletion that we describe indicates that SARS-CoV-2 is undergoing profound genomic changes. It is important to: i) confirm the spreading of this particular viral strain, and potentially of strains with other deletions in the nsp1 protein, both in the population of asymptomatic and pauci-symptomatic subjects, and ii) correlate these changes in nsp1 with potential decreased viral pathogenicity.

Mutational Screening of the Proteome of Sars-Cov-2 Isolates: Mutability of ORF3a, Nucleocapsid and Nsp2 Proteins (preprint)

The Sars-CoV-2 is the causative agent of the current coronavirus disease pandemic. To effectively fight this pathogen, it is important to understand its evolution and the mechanism of adaptation to the host. A software workflow has been utilized to scan 26,016 Sars-CoV-2 genomes available in GISAID databank to analyse the distribution and frequency of mutations in the corresponding proteomes. A filtering procedure has been applied to remove data inconsistencies and redundancies. The number of observed mutations appears proportional to protein sequence length except for ORF3a, Nucleocapsid and Nsp2 that seem to accept more mutations than expected. The most pervasive mutations of the three proteins have been reported and the most variable and conservative regions mapped onto the respective sequences. The results suggest that these proteins may have a role in the adaptation of virus to new hosts and influence its pathogenicity and replication. These considerations prompt the experimental study and characterization of the three proteins.

Inverse correlation between average monthly high temperatures and COVID-19-related death rates in different geographical areas. (preprint)

Background: With the aim of providing a dynamic evaluation of the effects of basic environmental parameters on COVID-19-related death rate, we assessed the correlation between average monthly high temperatures and population density, with death/rate (monthly number of deaths/1M people) for the months of March (start of the analysis and beginning of local epidemic in most of the Western World, except in Italy where it started in February) and April 2020 (continuation of the epidemic). Different geographical areas of the Northern Hemisphere in the United States and in Europe were selected in order to provide a wide range among the different parameters. The death rates were gathered from an available dataset. As a further control, we also included latitude, as a proxy for temperature. Methods: Utilizing a publicly available dataset, we retrieved data for the months of March and April 2020 for 25 areas in Europe and in the US. We computed the monthly number of deaths/1M people of confirmed COVID-19 cases and calculated the average monthly high temperatures and population density for all these areas. We determined the correlation between number of deaths/1M people and the average monthly high temperatures, the latitude and the population density. Results: We divided our analysis in two parts: analysis of the correlation among the different variables in the month of March and subsequent analysis in the month of April. The differences were then evaluated. In the month of March there was no statistical correlation between average monthly high temperatures of the considered geographical areas and number of deaths/1M people. However, a statistically significant inverse correlation became significant in the month of April between average monthly high temperatures (p=0.0043) and latitude (p=0.0253) with number of deaths/1M people. We also observed a statistically significant correlation between population density and number of deaths/1M people both in the month of March (p=0.0297) and in the month of April (p=0.0116), when three areas extremely populated (NYC, Los Angeles and Washington DC) were included in the calculation. Once these three areas were removed, the correlation was not statistically significant (p=0.1695 in the month of March, and p=0.7076 in the month of April). Conclusions: The number of COVID-19-related deaths/1M people was essentially the same during the month of March for all the geographical areas considered, indicating essentially that the infection was circulating quite uniformly except for Lombardy, Italy, where it started earlier. Lockdown measures were implemented between the end of March and beginning of April, except for Italy which started March 9 th . We observed a strong, statistically significant inverse correlation between average monthly high temperatures with the number of deaths/1M people. We confirmed the data by analyzing the correlation with the latitude, which can be considered a proxy for high temperature. Previous studies indicated a negative effect of high climate temperatures on Sars-COV-2 spreading. Our data indicate that social distancing measure are more successful in the presence of higher average monthly temperatures in reducing COVID-19-related death rate, and a high level of population density seems to negatively impact the effect of lockdown measures.

Impact of lockdown on Covid-19 Case Fatality Rate and Viral Mutations Spread in 7 Countries in Europe and North America. (preprint)

Background: Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) caused the first coronavirus disease 2019 (COVID-19) outbreak in China and has become a public health emergency of international concern. SARS-CoV-2 outbreak has been declared a pandemic by WHO on March 11th, 2020 and the same month several Countries put in place different lockdown restrictions and testing strategies in order to contain the spread of the virus. Methods: The calculation of the Case Fatality Rate of SARS-CoV-2 in the Countries selected was made by using the data available at https://github.com/owid/covi-19-data/tree/master/public/data. Case fatality rate was calculated as the ratio between the death cases due to COVID-19, over the total number of SARS-CoV-2 reported cases 14 days before. Standard Case Fatality Rate values were normalized by the Country-specific ρ factor, i.e. the number of PCR tests/1 million inhabitants over the number of reported cases/1 million inhabitants. Case-fatality rates between Countries were compared using proportion test. Post-hoc analysis in the case of more than two groups was performed using pairwise comparison of proportions and p-value was adjusted using Holm method.We also analyzed 487 genomic sequences from the GISAID database derived from patients infected by SARS-CoV-2 from January 2020 to April 2020 in Italy, Spain, Germany, France, Sweden, UK and USA. SARS-CoV-2 reference genome was obtained from the GenBank database (NC_045512.2). Genomes alignment was performed using Muscle and Jalview software. We, then, calculated the Case Fatality Rate of SARS-CoV-2 in the Countries selected. Results: In this study we analyse how different lockdown strategies and PCR testing capability adopted by Italy, France, Germany, Spain, Sweden, UK and USA have influenced the Case Fatality Rate and the viral mutations spread. We calculated case fatality rates by dividing the death number of a specific day by the number of patients with confirmed COVID-19 infection observed 14 days before and normalized by a ρ factor which takes into account the diagnostic PCR testing capability of each Country and the number of positive cases detected. We notice the stabilization of a clear pattern of mutations at sites nt241, nt3037, nt14408 and nt23403. A novel nonsynonymous SARS-CoV-2 mutation in the spike protein (nt24368) has been found in genomes sequenced in Sweden, which enacted a soft lockdown strategy.Conclusions: Strict lockdown strategies together with a wide diagnostic PCR testing of the population were correlated with a relevant decline of the case fatality rate in different Countries. The emergence of specific patterns of mutations concomitant with the decline in case fatality rate needs further confirmation and their biological significance remains unclear. 

Sars-CoV-2 Envelope and Membrane Proteins: Structural Differences Linked to Virus Characteristics? (preprint)

The Coronavirus Disease 2019 (COVID-19) is a new viral infection caused by the severe acute respiratory coronavirus 2 (SARS-CoV-2). Genomic analyses have revealed that SARS-CoV-2 is related to Pangolin and Bat coronaviruses. In this report, a structural comparison between the Sars-CoV-2 Envelope and Membrane proteins from different human isolates with homologous proteins from closely related viruses is described. The analyses here reported show the high structural similarity of Envelope and Membrane proteins to the counterparts from Pangolin and Bat coronavirus isolates. However, the comparisons have also highlighted structural differences specific of Sars-CoV-2 proteins which may be correlated to the cross-species transmission and/or to the properties of the virus. Structural modelling has been applied to map the variant sites onto the predicted three-dimensional structure of the Envelope and Membrane proteins.

Sars-CoV-2 Envelope and Membrane Proteins: Differences from Closely Related Proteins Linked to Cross-species Transmission? (preprint)

The Coronavirus disease (COVID-19) is a new viral infection caused by severe acute respiratory coronavirus 2 (SARS-CoV-2) that was initially reported in city of Wuhan, China and afterwards spread globally. Genomic analyses revealed that SARS-CoV-2 is phylogenetically related to severe acute respiratory syndrome-like (SARS-like) Pangolin and Bat coronavirus specific isolates. In this study we focused on two proteins of Sars-CoV-2 surface: Envelope protein and Membrane protein. Sequences from Sars-CoV-2 isolates and other closely related virus were collected from the GenBank through TBlastN searches. The retrieved sequences were multiply aligned with MAFFT. The Envelope protein is identical to the counterparts from Pangolin CoV MP798 isolate and Bat CoV isolates CoVZXC21, CoVZC45 and RaTG13. However, a substitution at position 69 where an Arg replace for Glu, and a deletion in position 70 corresponding to Gly or Cys in other Envelope proteins were found. The Membrane glycoprotein appears more variable with respect to the SARS CoV proteins than the Envelope: a heterogeneity at the N-terminal position, exposed to the virus surface, was found between Pangolin CoV MP798 isolate and Bat CoV isolates CoVZXC21, CoVZC45 and RaTG13. Mutations observed on Envelope protein are drastic and may have significant implications for conformational properties and possibly for protein-protein interactions. Mutations on Membrane protein may also be relevant because this protein cooperates with the Spike during the cell attachment and entry. Therefore, these mutations may influence interaction with host cells. The mutations that have been detected in these comparative studies may reflect functional peculiarities of the Sars-CoV-2 virus and may help explaining the epizootic origin the COVID-19 epidemic.

Emerging SARS-CoV-2 mutation hot spots include a novel RNA-dependent-RNA polymerase variant (preprint)

Background: SARS-CoV-2 is a RNA coronavirus responsible for the pandemic of the Severe Acute Respiratory Syndrome (COVID-19). RNA viruses are characterized by a high mutation rate, up to a million times higher than that of their hosts. Virus mutagenic capability depends upon several factors, including the fidelity of viral enzymes that replicate nucleic acids, as SARS-CoV-2 RNA dependent RNA Polymerase (RdRp). Mutation rate drives viral evolution and genome variability, thereby enabling viruses to escape host immunity and to develop drug resistance. Methods. We analyzed 220 genomic sequences from the GISAID database derived from patients infected by SARS-CoV-2 worldwide from December 2019 to mid-March 2020. SARS-CoV-2 reference genome was obtained from the GenBank database. Genomes alignment was performed using Clustal Omega. Mann-Whitney and Fisher-Exact tests were used to assess statistical significance.Results. We characterized 8 novel recurrent mutations of SARS-CoV-2, located at positions 1397, 2891, 14408, 17746, 17857, 18060, 23403 and 28881. Mutations in 2891, 3036, 14408, 23403 and 28881 positions are predominantly observed in Europe, whereas those located at positions 17746, 17857 and 18060 are exclusively present in North America. We noticed that the 14408 mutation, emerged for the first time in Europe in mid-February 2020, is present in the SARS-CoV-2 RdRp gene sequence. Viruses with RdRp mutation have a median of 3 point mutations [range: 2-5], otherwise they have a median of 1 mutation [range: 0-3] (p value < 0.001). Conclusions. These findings suggest that the virus is evolving and European, North American and Asian strains might coexist, each of them characterized by a different mutation pattern. The contribution of the mutated RdRp to this phenomenon needs to be investigated. To date, several drugs targeting RdRp enzymes are being employed for SARS-CoV-2 infection treatment. Some of them have a predicted binding moiety in a SARS-CoV-2 RdRp hydrophobic cleft, which is adjacent to the 14408 mutation we identified. Consequently, it is important to study and characterize SARS-CoV-2 RdRp mutation in order to assess possible drug-resistance viral phenotypes. It is also important to recognize whether the presence of some mutations might correlate with different SARS-CoV-2 mortality rates.

The 2019-new Coronavirus epidemic: evidence for virus evolution (preprint)

There is concern about a new coronavirus, the 2019-nCoV, as a global public health threat. In this article, we provide a preliminary evolutionary and molecular epidemiological analysis of this new virus. A phylogenetic tree has been built using the 15 available whole genome sequence of 2019-nCoV and 12 whole genome sequences highly similar sequences available in gene bank (5 from SARS, 2 from MERS and 5 from Bat SARS-like Coronavirus). FUBAR analysis shows that the Nucleocapsid and the Spike Glycoprotein has some sites under positive pressure while homology modelling helped to explain some molecular and structural differences between the viruses. The phylogenetic tree showed that 2019.nCoV significantly clustered with Bat SARS-like Coronavirus sequence isolated in 2015, whereas structural analysis revealed mutation in S and nucleocapsid proteins. From these results, 2019nCoV could be considered a coronavirus distinct from SARS virus, probably transmitted from bats or another host where mutations conferred upon it the ability to infect humans.