Origin of the COVID-19 virus has been intensely debated in the scientific community since the first infected cases were detected in December 2019. The disease has caused a global pandemic, leading to deaths of thousands of people across the world and thus finding origin of this novel coronavirus is important in responding and controlling the pandemic. Recent research results suggest that bats or pangolins might be the original hosts for the virus based on comparative studies using its genomic sequences. This paper investigates the COVID-19 virus origin by using artificial intelligence (AI) and raw genomic sequences of the virus. More than 300 genome sequences of COVID-19 infected cases collected from different countries are explored and analysed using unsupervised clustering methods. The results obtained from various AI-enabled experiments using clustering algorithms demonstrate that all examined COVID-19 virus genomes belong to a cluster that also contains bat and pangolin coronavirus genomes. This provides evidences strongly supporting scientific hypotheses that bats and pangolins are probable hosts for the COVID-19 virus. At the whole genome analysis level, our findings also indicate that bats are more likely the hosts for the COVID-19 virus than pangolins.

Origin of Novel Coronavirus (COVID-19): A Computational Biology Study using Artificial Intelligence

Every time a pandemic occurs, dozens of theories emerge to attribute the origin of the event to different facts. The COVID-19 pandemic that has hit virtually all the globe has been no exception. What is known so far about the origin of the virus that causes COVID 19? The first investigations on the origin of this disease have determined that it is a new type of virus, the origin of which is most likely zoonotic.

[What is the origin of SARS-CoV-2?]

The emerging coronavirus disease (COVID-19) swept across the world, affecting more than 200 countries and territories. Genomic analysis suggests that the COVID-19 virus originated in bats and transmitted to humans through unknown intermediate hosts in the Wuhan seafood market, China, in December of 2019. This virus belongs to the Betacoronavirus group, the same group of the 2003 severe acute respiratory syndrome coronavirus (SARS-CoV), and for the similarity, it was named SARS-CoV-2. Given the lack of registered clinical therapies or vaccines, many physicians and scientists are investigating previously used clinical drugs for COVID-19 treatment. In this review, we aim to provide an overview of the CoVs origin, pathogenicity, and genomic structure, with a focus on SARS-CoV-2. Besides, we summarize the recently investigated drugs that constitute an option for COVID-19 treatment.

The Human Coronavirus Disease COVID-19: Its Origin, Characteristics, and Insights into Potential Drugs and Its Mechanisms

A novel coronavirus has caused thousands of human infections in China since December 2019, raising a global public health concern. Recent studies (Huang et al ., Chan et al ., and Zhou et al .) have provided timely insights into its origin and ability to spread among humans, informing infection prevention and control practices.

Unveiling the Origin and Transmission of 2019-nCoV

A novel coronavirus has caused thousands of human infections in China since December 2019, raising a global public health concern. Recent studies (Huang et al., Chan et al., and Zhou et al.) have provided timely insights into its origin and ability to spread among humans, informing infection prevention and control practices.

The proximal origin of SARS-CoV-2

The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19 / SARS-CoV-2 / 2019-nCoV), is a global threat to the human population. Here, we briefly summarize the available data for the zoonotic origins of HCoV-19, with reference to the other two epidemics of highly virulent coronaviruses, SARS-CoV and MERS-CoV, which cause severe pneumonia in humans. We propose to intensify future efforts for tracing the origins of HCoV-19, which is a very important scientific question for the control and prevention of the pandemic.

Zoonotic origins of human coronavirus 2019 (HCoV-19 / SARS-CoV-2): why is this work important?

Strategies to trace back the origin of COVID-19

In the 5th February 2020 issue of Journal of Medical Virology a paper was published by Giovannetti et al., entitled "The first two cases of 2019-nCoV in Italy: where they come from?"1 . In this paper a phylogenetic and evolutionary analysis was applied to the virus identified in the first two subjects diagnosed in Italy with 2019-nCoV infection, recently renamed SARS-CoV-22 , two Chinese spouses arrived in Italy for tourism. The diagnosis was performed by the virology team under direction of Maria R. Capobianchi, at the National Institute of Infectious Diseases (INMI) in Rome, Italy, where the patients are currently hospitalized. This article is protected by copyright. All rights reserved.

About the origin of the first two Sars-CoV-2 infections in Italy: inference not supported by appropriate sequence analysis.

The 2019 novel coronavirus (2019-nCoV) have emerged from Wuhan, China. Studying the epidemic dynamics is crucial for further surveillance and control of the outbreak. We employed a Bayesian framework to infer the time-calibrated phylogeny and the epidemic dynamics represented by the effective reproductive number (Re) changing over time from the genomic sequences available from GISAID. The origin time is estimated to be December 17, 2019 (95% CI: December 5, 2019 – December 23, 2019). The median estimate of Re ranges from 0.2 to 2.2 and changes drastically over time. This study provides an early insight of the 2019-nCoV epidemic.

Origin time and epidemic dynamics of the 2019 novel coronavirus

OBJECTIVE: Turkey is one of the latest countries that COVID-19 disease was reported, with the first case on March 11, 2020, and since then, Istanbul became the epicenter of the pandemic in Turkey. Here, we reveal sequences of the virus isolated from three different patients with various clinical presentations. METHODS: Nasopharyngeal swab specimens of the patients were tested positive for the COVID-19 by qRT-PCR. Viral RNA extraction was performed from the same swab samples. Amplicon based libraries were prepared and sequenced using the Illumina NextSeq platform. Raw sequencing data were processed for variant calling and generating near-complete genome sequences. All three genomes were evaluated and compared with other worldwide isolates. RESULTS: The patients showed various clinics (an asymptomatic patient, patient with mild disease, and with severe pulmonary infiltration). Amplicon-based next-generation sequencing approach successfully applied to generate near-complete genomes with an average depth of 2.616. All three viral genomes carried the D614G variant (G clade according to GISAID classification) with implications for the origin of a spread first through China to Europe then to Istanbul. CONCLUSION: Here, we report the viral genomes circulating in Istanbul for the first time. Further sequencing of the virus isolates may enable us to understand variations in disease presentation and association with viral factors if there is any. In addition, the sequencing of more viral genomes will delineate the spread of disease and will guide and ease the necessary measures taken to stem the spread of the novel coronavirus.

The origin of SARS-CoV-2 in Istanbul: Sequencing findings from the epicenter of the pandemic in Turkey

About the origin of the first two Sars-CoV-2 infections in Italy: inference not supported by appropriate sequence analysis

Coronavirus has emerged as a global health threat due to its accelerated geographic spread over the last two decades. This article reviews the current state of knowledge concerning the origin, transmission, diagnosis and management of coronavirus disease 2019 (COVID-19). Historically, it has caused two pandemics: severe acute respiratory syndrome and Middle East respiratory syndrome followed by the present COVID-19 that emerged from China. The virus is believed to be acquired from zoonotic source and spreads through direct and contact transmission. The symptomatic phase manifests with fever, cough and myalgia to severe respiratory failure. The diagnosis is confirmed using reverse transcriptase PCR. Management of COVID-19 is mainly by supportive therapy along with mechanical ventilation in severe cases. Preventive strategies form the major role in reducing the public spread of virus along with successful disease isolation and community containment. Development of a vaccine to eliminate the virus from the host still remains an ongoing challenge.

Origin, transmission, diagnosis and management of coronavirus disease 2019 (COVID-19)

Origin and evolution of the 2019 novel coronavirus

Origin and Evolution of the 2019 Novel Coronavirus

OBJECTIVE SARS-CoV-2 is responsible for the present coronavirus pandemic and some suggestions were made about its possible artificial origin. We, therefore, compared SARS-CoV-2 with such known viruses that were prepared in the laboratory and other relevant natural strains to estimate their genetic relatedness. MATERIALS AND METHODS BLAST and clustalW were used to identify and align viral sequences of SARS-CoV-2 to other animal coronaviruses (human, bat, mouse, pangolin) and related artificial constructs. Phylogenetics trees were then prepared using iTOL. RESULTS Our study supports the notion that known artificial coronaviruses, including the chimeric SL-SHC014-MA15 synthesized in 2015, differ too much from SARS-CoV-2 to hypothesize an artificial origin of the latter. On the contrary, our data support the natural origin of the COVID-19 virus, likely derived from bats, possibly transferred to pangolins, before spreading to man. CONCLUSIONS Speculations about the artificial origin of SARS-CoV-2 are most likely unfounded. On the contrary, when carefully handled, engineered organisms provide a unique opportunity to study biological systems in a controlled fashion. Biotechnology is a powerful tool to advance medical research and should not be abandoned because of irrational fears.

Bioinformatic analysis indicates that SARS-CoV-2 is unrelated to known artificial coronaviruses.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a positive-sense single stranded RNA virus with high human transmissibility. This study generated Whole Genome data to determine the origin and pattern of transmission of SARS-CoV-2 from the first six cases tested in The Gambia. Total RNA from SARS-CoV-2 was extracted from inactivated nasopharyngeal-oropharyngeal swabs of six cases and converted to cDNA following the ARTIC COVID-19 sequencing protocol. Libraries were constructed with the NEBNext ultra II DNA library prep kit for Illumina and Oxford Nanopore Ligation sequencing kit and sequenced on Illumina MiSeq and Nanopore GridION, respectively. Sequencing reads were mapped to the Wuhan reference genome and compared to eleven other SARS-CoV-2 strains of Asian, European and American origins. A phylogenetic tree was constructed with the consensus genomes for local and non-African strains. Three of the Gambian strains had a European origin (UK and Spain), two strains were of Asian origin (Japan). In The Gambia, Nanopore and Illumina sequencers were successfully used to identify the sources of SARS-CoV-2 infection in COVID-19 cases.

Origin of imported SARS-CoV-2 strains in The Gambia identified from Whole Genome Sequences

BACKGROUND COVID-19 in China was first reported to the World Health Organization on December 31st 2019. The first cases were officially identified around December 8th 2019. The origin of COVID-19 is not confirmed, but half the early cases were linked to a seafood market in Wuhan. The first two documented cases did not attend the seafood market. News reports, social media and informal sources may contain information about outbreaks prior to formal notification. OBJECTIVE To identify early signals of pneumonia and/or severe acute respiratory illness (SARI) in China, prior to official recognition of the COVID 19 outbreak in December 2019, using open source data. METHODS In order to capture early reports we searched an open source epidemic observatory, Epiwatch from 1st October2019 in China, for severe acute respiratory illness (SARI) or pneumonia related illnesses. Google and Chinese search engine Baidu were used. RESULTS There was an increase in reports following the official notification of COVID 19 to WHO on December 31 2019, and a retracted report on December 26th 2019. A report of severe pneumonia was identified on November 22 2019 in Xiangyang, Index patient was retrospectively identified on 17 November. CONCLUSIONS The lack of reports of a SARI outbreaks prior to December 31st, with a retracted report on December 26th suggests media censorship, given formal reports that cases began on December 8th. However, the findings also support relatively recent origin of COVID-19 in November 2019. The case reported on November 22nd was transferred to Wuhan approximately 1 incubation period before the first reported cases on December 8th, and should be further investigated, as only half of the early cases had exposure to the seafood market. It has since been reported that another case of COVID 19 has been retrospectively identified in Hubei on November 17th, confirming that the infection was present prior to December. CLINICALTRIAL

Using open-source intelligence to detect early signals of COVID-19 in China, Descriptive study.

Covid19 origin and transmission to humans. Covid19 infection began in Wuhan (Hubei, China) in December, 2019. Although to date it is considered that Covid19 originates from bats (96.2% overall genome sequence identity) (1), the type of intermediate animals that caused the transmission to humans remains unknown (2-4). Zhou et al (1) mentioned that 'Direct contact with intermediate host animals or consumption of wild animals was suspected to be the main route of SARSCoV2 transmission. However, the source(s) and transmission routine(s) of SARSCoV2 remain elusive' (1).

[Editorial] Possibility of transmission through dogs being a contributing factor to the extreme Covid19 outbreak in North Italy

OBJECTIVE: SARS-CoV-2 is responsible for the present coronavirus pandemic and some suggestions were made about its possible artificial origin. We, therefore, compared SARS-CoV-2 with such known viruses that were prepared in the laboratory and other relevant natural strains to estimate their genetic relatedness. MATERIALS AND METHODS: BLAST and clustalW were used to identify and align viral sequences of SARS-CoV-2 to other animal coronaviruses (human, bat, mouse, pangolin) and related artificial constructs. Phylogenetics trees were then prepared using iTOL. RESULTS: Our study supports the notion that known artificial coronaviruses, including the chimeric SL-SHC014-MA15 synthesized in 2015, differ too much from SARS-CoV-2 to hypothesize an artificial origin of the latter. On the contrary, our data support the natural origin of the COVID-19 virus, likely derived from bats, possibly transferred to pangolins, before spreading to man. CONCLUSIONS: Speculations about the artificial origin of SARS-CoV-2 are most likely unfounded. On the contrary, when carefully handled, engineered organisms provide a unique opportunity to study biological systems in a controlled fashion. Biotechnology is a powerful tool to advance medical research and should not be abandoned because of irrational fears.

Bioinformatic analysis indicates that SARS-CoV-2 is unrelated to known artificial coronaviruses

The novel coronavirus, SARS-CoV-2, causes the unfathomable pandemic in the history of humankind. Bangladesh is also a victim of this critical situation. To investigate the genomic features of the pathogen, the first complete genome of the virus has very recently been published. Therefore, the long awaiting questions regarding the possible origin and typing of the strain(s) can now be answered. Here, we endeavor to mainly discuss the published reports or online-accessed data (results) regarding those issues and presented a comprehensive picture of the typing of the virus alongside the probable origin of the sub-clade containing Bangladeshi strain. Our observation suggested that this strain might have originated from the United Kingdom (UK) or other European countries epidemiologically linked to the UK. According to different genotyping classification schemes, this strain belongs to A2a clade under G major clade, is of B and/or L type, and is a SARS-CoV-2a sub-strain. In the forwarding days, randomized genome data will certainly voluminate in Bangladesh, however because of globalization and immigrant movements, we urgently need a mass regional sequencing approach targeting the partial or complete genome that can link the epidemiological data and may help in further clinical interventions. This article is protected by copyright. All rights reserved.

Understanding the possible origin and genotyping of first Bangladeshi SARS-CoV-2 strain

Coronavirus has emerged as a global health treat due to its accelerated geographic spread over the last two decades. This article reviews the current state of knowledge concerning the origin, transmission, diagnosis and management of coronavirus disease 2019 (COVID-19). Historically, it has caused two pandemics: severe acute respiratory syndrome and Middle East respiratory syndrome followed by the present COVID-19 that emerged from China. The virus is believed to be acquired from zoonotic source and spreads through direct and contact transmission. The symptomatic phase manifests with fever, cough and myalgia to severe respiratory failure. The diagnosis is confirmed using reverse transcriptase PCR. Management of COVID-19 is mainly by supportive therapy along with mechanical ventilation in severe cases. Preventive strategies form the major role in reducing the public spread of virus along with successful disease isolation and community containment. Development of a vaccine to eliminate the virus from the host still remains an ongoing challenge.

Origin, transmission, diagnosis and management of coronavirus disease 2019 (COVID-19).

The initial cases of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) occurred in Wuhan, China, in December 2019 and swept the world by 23 June 2020 with 8,993,659 active cases, 469,587 deaths across 216 countries, areas or territories. This strongly implies global transmission occurred before the lockdown of China. However, the initial source's transmission routes of SARS-CoV-2 remain obscure and controversial. Research data suggest bat (RaTG13) and pangolin carried CoV were the proximal source of SARS-CoV-2. In this study, we used systematic phylogenetic analysis of Coronavirinae subfamily along with wild type human SARS-CoV, MERS-CoV, and SARS-CoV-2 strains. The key residues of the receptor-binding domain (RBD) and O-linked glycan were compared. SARS-CoV-2 strains were clustered with RaTG13 (97.41% identity), Pangolin-CoV (92.22% identity) and Bat-SL-CoV (80.36% identity), forms a new clade-2 in lineage B of beta-CoV. The alignments of RBD contact residues to ACE2 justified? Those SARS-CoV-2 strains sequences were 100% identical by each other, significantly varied in RaTG13 and pangolin-CoV. SARS-CoV-2 has a polybasic cleavage site with an inserted sequence of PRRA compared to RaTG13 and only PRR to pangolin. Only serine (Ser) in pangolin and both threonine (Thr) and serine (Ser) O-linked glycans were seen in RaTG13, suggesting that a detailed study needed in Pangolin (Manis javanica) and bat (Rhinolophus affinis) related CoV. This article is protected by copyright. All rights reserved.

An update on origin of SARS-CoV-2: Despite closest identity, bat (RaTG13) and Pangolin derived Coronaviruses varied in the critical binding site and O-linked glycan residues

Covid‑19 origin and transmission to humans. Covid‑19 infection began in Wuhan (Hubei, China) in December, 2019. Although to date it is considered that Covid‑19 originates from bats (96.2% overall genome sequence identity) (1), the type of intermediate animals that caused the transmission to humans remains unknown (2-4). Zhou et al (1) mentioned that 'Direct contact with intermediate host animals or consumption of wild animals was suspected to be the main route of SARS‑CoV‑2 transmission. However, the source(s) and transmission routine(s) of SARS‑CoV‑2 remain elusive' (1).

Possibility of transmission through dogs being a contributing factor to the extreme Covid-19 outbreak in North Italy

A group of 27 prominent public health scientists from outside China is pushing back against a steady stream of stories and even a scientific paper suggesting a laboratory in Wuhan, China, may be the origin of the outbreak of COVID-19 “The rapid, open, and transparent sharing of data on this outbreak is now being threatened by rumours and misinformation around its origins,” the scientists, from nine countries, write in a statement published online by The Lancet yesterday

Scientists ‘strongly condemn’ rumors and conspiracy theories about origin of coronavirus outbreak ;Science ;AAAS

Is SARS-CoV-2 originated from laboratory? A rebuttal to the claim of formation via laboratory recombination

Origins of MERS-CoV, and lessons for 2019-nCoV

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for the coronavirus disease of 2019 (COVID-19). First identified in Wuhan (Hubei, China) in December of 2019, it has since been declared a pandemic by the World Health Organization in March of 2020. In this study, we will provide a brief review of viral origin, identification, symptoms, transmission, diagnosis, and potential treatment strategies for the newly identified SARS-CoV-2 strain.

Brief Review on COVID-19: The 2020 Pandemic Caused by SARS-CoV-2

Probable Pangolin Origin of SARS-CoV-2 Associated with the COVID-19 Outbreak

In late December 2019, some cases of atypical pneumonia, at that time of unknown origin, were reported in Wuhan, China. Days later, the etiologic agent was identified as a new coronavirus. This new coronavirus was called SARS-CoV-2 and the disease it produces was named COVID-19. The origin of this new virus is presumed zoonotic, with bats being its probable vector. Due to the rapid number of infections and deaths that occurred first in China and later around the world, the infection of this virus quickly went from being an isolated outbreak in a Chinese region to becoming a health emergency of international concern and later, a pandemic. The purpose of this review is to study the most relevant and current information on the pathogen, as well as epidemiology, pathology, clinical features, transmission, prevention, and treatment of the disease.

Pandemia COVID-19, la nueva emergencia sanitaria de preocupación internacional: una revisión./ [Pandemic COVID-19, the new health emergency of international concern: a review]

The coronavirus disease 19 (COVID-19) is a highly transmittable and pathogenic viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in Wuhan, China and spread around the world. Genomic analysis revealed that SARS-CoV-2 is phylogenetically related to severe acute respiratory syndrome-like (SARS-like) bat viruses, therefore bats could be the possible primary reservoir. The intermediate source of origin and transfer to humans is not known, however, the rapid human to human transfer has been confirmed widely. There is no clinically approved antiviral drug or vaccine available to be used against COVID-19. However, few broad-spectrum antiviral drugs have been evaluated against COVID-19 in clinical trials, resulted in clinical recovery. In the current review, we summarize and comparatively analyze the emergence and pathogenicity of COVID-19 infection and previous human coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV). We also discuss the approaches for developing effective vaccines and therapeutic combinations to cope with this viral outbreak.

COVID-19 infection: Origin, transmission, and characteristics of human coronaviruses

Origine de SARS-CoV-2 : le probable et le possible

Bats are presumed reservoirs of diverse coronaviruses (CoVs) including progenitors of Severe Acute Respiratory Syndrome (SARS)-CoV and SARS-CoV-2, the causative agent of COVID-19. However, the evolution and diversification of these coronaviruses remains poorly understood. We used a Bayesian statistical framework and sequence data from all known bat-CoVs (including 630 novel CoV sequences) to study their macroevolution, cross-species transmission, and dispersal in China. We find that host-switching was more frequent and across more distantly related host taxa in alpha-than beta-CoVs, and more highly constrained by phylogenetic distance for beta-CoVs. We show that inter-family and -genus switching is most common in Rhinolophidae and the genus Rhinolophus. Our analyses identify the host taxa and geographic regions that define hotspots of CoV evolutionary diversity in China that could help target bat-CoV discovery for proactive zoonotic disease surveillance. Finally, we present a phylogenetic analysis suggesting a likely origin for SARS-CoV-2 in Rhinolophus spp. bats.

Origin and cross-species transmission of bat coronaviruses in China

To investigate the genetic diversity, time origin, and evolutionary history of the 2019-nCoV outbreak in China and Thailand, a total of 12 genome sequences of the virus with known sampling date (24 December 2019 and 13 January 2020) and geographic location (primarily Wuhan city, Hubei Province, China, but also Bangkok, Thailand) were analyzed. Phylogenetic and likelihood-mapping analyses of these genome sequences were performed. On the basis of our results, the star-like signal and topology of 2019-nCoV may be indicative of potentially large "first generation" human-to-human virus transmission. We estimated that 2019-nCoV likely originated in Wuhan on 9 November 2019 (95% credible interval: 25 September 2019 and 19 December 2019), and that Wuhan is the major hub for the spread of the 2019-nCoV outbreak in China and elsewhere. Our results could be useful for designing effective prevention strategies for 2019-nCoV in China and beyond.

Potential of large "first generation" human-to-human transmission of 2019-nCoV

BACKGROUND: COVID-19 in China was first reported to the World Health Organization on December 31st 2019. The first cases were officially identified around December 8th 2019. The origin of COVID-19 is not confirmed, but half the early cases were linked to a seafood market in Wuhan. The first two documented cases did not attend the seafood market. News reports, social media and informal sources may contain information about outbreaks prior to formal notification. OBJECTIVE: To identify early signals of pneumonia and/or severe acute respiratory illness (SARI) in China, prior to official recognition of the COVID 19 outbreak in December 2019, using open source data. METHODS: In order to capture early reports we searched an open source epidemic observatory, Epiwatch from 1st October2019 in China, for severe acute respiratory illness (SARI) or pneumonia related illnesses. Google and Chinese search engine Baidu were used. RESULTS: There was an increase in reports following the official notification of COVID 19 to WHO on December 31 2019, and a retracted report on December 26th 2019. A report of severe pneumonia was identified on November 22 2019 in Xiangyang, Index patient was retrospectively identified on 17 November. CONCLUSIONS: The lack of reports of a SARI outbreaks prior to December 31st, with a retracted report on December 26th suggests media censorship, given formal reports that cases began on December 8th. However, the findings also support relatively recent origin of COVID-19 in November 2019. The case reported on November 22nd was transferred to Wuhan approximately 1 incubation period before the first reported cases on December 8th, and should be further investigated, as only half of the early cases had exposure to the seafood market. It has since been reported that another case of COVID 19 has been retrospectively identified in Hubei on November 17th, confirming that the infection was present prior to December.

Using open-source intelligence to detect early signals of COVID-19 in China, Descriptive study

In December 2019, an outbreak of pneumonia of unknown origin was reported in Wuhan, Hubei Province, China. Pneumonia cases were epidemiologically linked to the Huanan Seafood Wholesale Market. Inoculation of respiratory samples into human airway epithelial cells, Vero E6 and Huh7 cell lines, led to the isolation of a novel respiratory virus whose genome analysis showed it to be a novel coronavirus related to SARS-CoV, and therefore named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 is a betacoronavirus belonging to the subgenus Sarbecovirus. The global spread of SARS-CoV-2 and the thousands of deaths caused by coronavirus disease (COVID-19) led the World Health Organization to declare a pandemic on 12 March 2020. To date, the world has paid a high toll in this pandemic in terms of human lives lost, economic repercussions and increased poverty. In this review, we provide information regarding the epidemiology, serological and molecular diagnosis, origin of SARS-CoV-2 and its ability to infect human cells, and safety issues. Then we focus on the available therapies to fight COVID-19, the development of vaccines, the role of artificial intelligence in the management of the pandemic and limiting the spread of the virus, the impact of the COVID-19 epidemic on our lifestyle, and preparation for a possible second wave.

The COVID-19 pandemic

COVID-19 is a new type of coronavirus disease which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It originated in China in the month of December 2019 and quickly started to spread within the country. On 31st December 2019, it was first reported to country office of World Health Organization (WHO) in China. Since then, it has spread to most of the countries around the globe. However, there has been a recent rise in trend in believing that it would go away during summer days, which has not yet been properly investigated. In this paper, relationship of daily number of confirmed cases of COVID-19 with three environmental factors, viz. maximum relative humidity (RH_max), maximum temperature (T_max) and highest wind speed (WS_max), considering the incubation period, have been investigated statistically, for four of the most affected places of China, viz. Beijing, Chongqing, Shanghai, Wuhan and five of the most affected places of Italy, viz. Bergamo, Cremona, Lodi, Milano. It has been found that the relationship with maximum relative humidity and highest wind is mostly negligible, whereas relationship with maximum temperature is ranging between negligible to moderate.

Statistical investigation of relationship between spread of coronavirus disease (COVID-19) and environmental factors based on study of four mostly affected places of China and five mostly affected places of Italy

The fast-growing outbreak of the 2019 novel coronavirus (2019-nCoV), which originated from Wuhan locating in central China at the end of 2019, spread to multiple cities in merely a month. Although the mortality of this disease was lower than that of SARS, the incredible contagiousness was much higher than SRAS-CoV. Because of the tremendous clout of 2019-nCoV, it is essential to hold more details about it and monitor its future evolution. This mini review consequently summarizes the key elements of epidemiology features, providing updated relevant findings and novel insights related to 2019-nCoV.

Epidemiological Features of the 2019 Novel Coronavirus Outbreak in China.

The SARS-CoV-2 outbreak: What we know

BACKGROUND: SARS-CoV-2 began spreading in December 2019 and has since become a pandemic that has impacted many aspects of human society. Several issues concerning the origin, time of introduction to humans, evolutionary patterns, and underlying force driving the SARS-CoV-2 outbreak remain unclear. METHOD: Genetic variation in 137 SARS-CoV-2 genomes and related coronaviruses as of 2/23/2020 was analyzed. RESULT: After correcting for mutational bias, the excess of low frequency mutations on both synonymous and nonsynonymous sites was revealed which is consistent with the recent outbreak of the virus. In contrast to adaptive evolution previously reported for SARS-CoV during its brief epidemic in 2003, our analysis of SARS-CoV-2 genomes shows signs of relaxation. The sequence similarity in the spike receptor binding domain between SARS-CoV-2 and a sequence from pangolin is probably due to an ancient intergenomic introgression that occurred approximately 40 years ago. The current outbreak of SARS-CoV-2 was estimated to have originated on 12/11/2019 (95% HPD 11/13/2019-12/23/2019). The effective population size of the virus showed an approximately 20-fold increase from the onset of the outbreak to the lockdown of Wuhan (1/23/2020) and ceased to increase afterwards, demonstrating the effectiveness of social distancing in preventing its spread. Two mutations, 84S in orf8 protein and 251 V in orf3 protein, occurred coincidentally with human intervention. The former first appeared on 1/5/2020 and plateaued around 1/23/2020. The latter rapidly increased in frequency after 1/23/2020. Thus, the roles of these mutations on infectivity need to be elucidated. Genetic diversity of SARS-CoV-2 collected from China is two times higher than those derived from the rest of the world. A network analysis found that haplotypes collected from Wuhan were interior and had more mutational connections, both of which are consistent with the observation that the SARS-CoV-2 outbreak originated in China. CONCLUSION: SARS-CoV-2 might have cryptically circulated within humans for years before being discovered. Data from the early outbreak and hospital archives are needed to trace its evolutionary path and determine the critical steps required for effective spreading.

The origin and underlying driving forces of the SARS-CoV-2 outbreak

Mutation and adaptation have driven the co-evolution of coronaviruses (CoVs) and their hosts, including human beings, for thousands of years. Before 2003, two human CoVs (HCoVs) were known to cause mild illness, such as common cold. The outbreaks of severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS) have flipped the coin to reveal how devastating and life-threatening an HCoV infection could be. The emergence of SARS-CoV-2 in central China at the end of 2019 has thrusted CoVs into the spotlight again and surprised us with its high transmissibility but reduced pathogenicity compared to its sister SARS-CoV. HCoV infection is a zoonosis and understanding the zoonotic origins of HCoVs would serve us well. Most HCoVs originated from bats where they are non-pathogenic. The intermediate reservoir hosts of some HCoVs are also known. Identifying the animal hosts has direct implications in the prevention of human diseases. Investigating CoV-host interactions in animals might also derive important insight on CoV pathogenesis in humans. In this review, we present an overview of the existing knowledge about the seven HCoVs, with a focus on the history of their discovery as well as their zoonotic origins and interspecies transmission. Importantly, we compare and contrast the different HCoVs from a perspective of virus evolution and genome recombination. The current CoV disease 2019 (COVID-19) epidemic is discussed in this context. In addition, the requirements for successful host switches and the implications of virus evolution on disease severity are also highlighted.

Zoonotic origins of human coronaviruses

The COVID-19 pandemic.

BACKGROUND: SARS-CoV-2 began spreading in December 2019 and has since become a pandemic that has impacted many aspects of human society. Several issues concerning the origin, time of introduction to humans, evolutionary patterns, and underlying force driving the SARS-CoV-2 outbreak remain unclear. METHOD: Genetic variation in 137 SARS-CoV-2 genomes and related coronaviruses as of 2/23/2020 was analyzed. RESULT: After correcting for mutational bias, the excess of low frequency mutations on both synonymous and nonsynonymous sites was revealed which is consistent with the recent outbreak of the virus. In contrast to adaptive evolution previously reported for SARS-CoV during its brief epidemic in 2003, our analysis of SARS-CoV-2 genomes shows signs of relaxation. The sequence similarity in the spike receptor binding domain between SARS-CoV-2 and a sequence from pangolin is probably due to an ancient intergenomic introgression that occurred approximately 40 years ago. The current outbreak of SARS-CoV-2 was estimated to have originated on 12/11/2019 (95% HPD 11/13/2019–12/23/2019). The effective population size of the virus showed an approximately 20-fold increase from the onset of the outbreak to the lockdown of Wuhan (1/23/2020) and ceased to increase afterwards, demonstrating the effectiveness of social distancing in preventing its spread. Two mutations, 84S in orf8 protein and 251 V in orf3 protein, occurred coincidentally with human intervention. The former first appeared on 1/5/2020 and plateaued around 1/23/2020. The latter rapidly increased in frequency after 1/23/2020. Thus, the roles of these mutations on infectivity need to be elucidated. Genetic diversity of SARS-CoV-2 collected from China is two times higher than those derived from the rest of the world. A network analysis found that haplotypes collected from Wuhan were interior and had more mutational connections, both of which are consistent with the observation that the SARS-CoV-2 outbreak originated in China. CONCLUSION: SARS-CoV-2 might have cryptically circulated within humans for years before being discovered. Data from the early outbreak and hospital archives are needed to trace its evolutionary path and determine the critical steps required for effective spreading.

Where did SARS-CoV-2 come from?

Abstract The original coronavirus disease (COVID-19) outbreak in Wuhan, China has become a global pandemic. By tracking the earliest 118 COVID-19 cases in Canada, we produced a Voronoi treemap to show the travel origins of the country’s earliest COVID-19 cases. By March 11, 2020, even though the majority (64.1%) of the world’s COVID-19 confirmed cases still had their origin in China, only 7.6% of Canada’s first 118 COVID-19 cases arose due in travelers to China. The most commonly reported travel history among the 118 cases originated from the Middle East, the United States, and Europe. Thus, in retrospect, broadening of early screening tools and travel restrictions to countries and regions outside China may help control global COVID-19 spread.

Tracking the origin of early COVID-19 cases in Canada

The original coronavirus disease (COVID-19) outbreak in Wuhan, China has become a global pandemic. By tracking the earliest 118 COVID-19 cases in Canada, we produced a Voronoi treemap to show the travel origins of the country's earliest COVID-19 cases. By March 11, 2020, even though the majority (64.1%) of the world's COVID-19 confirmed cases still had their origin in China, only 7.6% of Canada's first 118 COVID-19 cases arose due in travelers to China. The most commonly reported travel history among the 118 cases originated from the Middle East, the United States, and Europe. Thus, in retrospect, broadening of early screening tools and travel restrictions to countries and regions outside China may help control global COVID-19 spread.

Coronaviruses are the well-known cause of severe respiratory, enteric and systemic infections in a wide range of hosts including man, mammals, fish, and avian. The scientific interest on coronaviruses increased after the emergence of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) outbreaks in 2002-2003 followed by Middle East Respiratory Syndrome CoV (MERS-CoV). This decade’s first CoV, named 2019-nCoV, emerged from Wuhan, China, and declared as ‘Public Health Emergency of International Concern’ on January 30(th), 2020 by the World Health Organization (WHO). As on February 4, 2020, 425 deaths reported in China only and one death outside China (Philippines). In a short span of time, the virus spread has been noted in 24 countries. The zoonotic transmission (animal-to-human) is suspected as the route of disease origin. The genetic analyses predict bats as the most probable source of 2019-nCoV though further investigations needed to confirm the origin of the novel virus. The ongoing nCoV outbreak highlights the hidden wild animal reservoir of the deadly viruses and possible threat of spillover zoonoses as well. The successful virus isolation attempts have made doors open for developing better diagnostics and effective vaccines helping in combating the spread of the virus to newer areas.

Emerging novel coronavirus (2019-nCoV)—current scenario, evolutionary perspective based on genome analysis and recent developments

Since the early 2000s, three novel zooanthroponous coronaviruses (Betacoronavirus) have emerged. The first outbreak of infection (SARS) caused by SARS-CoV virus occurred in the fall of 2002 in China (Guangdong Province). A second outbreak (MERS) associated with the new MERS-CoV virus appeared in Saudi Arabia in autumn 2012. The third epidemic, which turned into a COVID-19 pandemic caused by SARS-CoV-2 virus, emerged in China (Hubei Province) in the autumn 2019. This review focuses on ecological and genetic aspects that lead to the emergence of new human zoanthroponous coronaviruses. The main mechanism of adaptation of zoonotic betacoronaviruses to humans is to changes in the receptor-binding domain of surface protein (S), as a result of which it gains the ability to bind human cellular receptors of epithelial cells in respiratory and gastrointestinal tract. This process is caused by the high genetic diversity and variability combined with frequent recombination, during virus circulation in their natural reservoir - bats (Microchiroptera, Chiroptera). Appearance of SARS-CoV, SARS-CoV-2 (subgenus Sarbecovirus), and MERS (subgenus Merbecovirus) viruses is a result of evolutionary events occurring in bat populations with further transfer of viruses to the human directly or through the intermediate vertebrate hosts, ecologically connected with bats. This review is based on the report at the meeting «Coronavirus - a global challenge to science» of the Scientific Council «Life Science» of the Russian Academy of Science: Lvov D.K., Alkhovsky S.V., Burtseva E.I. COVID-19 pandemic sources: origin, biology and genetics of coronaviruses of SARS-CoV, SARS-CoV-2, MERS-CoV (Conference hall of Presidium of RAS, 14 Leninsky Prospect, Moscow, Russia. April 16, 2020).

[Source of the COVID-19 pandemic: ecology and genetics of coronaviruses (Betacoronavirus: Coronaviridae) SARS-CoV, SARS-CoV-2 (subgenus Sarbecovirus), and MERS-CoV (subgenus Merbecovirus).]

Reanalysis of the epidemic curve from the initial cluster of cases with novel coronavirus (2019-nCoV) in December 2019 indicates substantial human-to-human transmission. It is possible that the common exposure history at a seafood market in Wuhan originated from the human-to-human transmission events within the market, and the early, strong emphasis that market exposure indicated animal-to-human transmission was potentially the result of observer bias. To support the hypothesis of zoonotic origin of 2019-nCoV stemming from the Huanan seafood market, the index case should have had exposure history related to the market and the virus should have been identified from animals sold at the market. As these requirements remain unmet, zoonotic spillover at the market must not be overemphasized.

Initial Cluster of Novel Coronavirus (2019-nCoV) Infections in Wuhan, China Is Consistent with Substantial Human-to-Human Transmission

Abstract There is a current worldwide outbreak of the novel coronavirus Covid-19 (coronavirus disease 2019; the pathogen called SARS-CoV-2; previously 2019-nCoV), which originated from Wuhan in China and has now spread to 6 continents including 66 countries, as of 24:00 on March 2, 2020. Governments are under increased pressure to stop the outbreak from spiraling into a global health emergency. At this stage, preparedness, transparency, and sharing of information are crucial to risk assessments and beginning outbreak control activities. This information should include reports from outbreak site and from laboratories supporting the investigation. This paper aggregates and consolidates the epidemiology, clinical manifestations, diagnosis, treatments and preventions of this new type of coronavirus.

The SARS-CoV-2 outbreak: What we know

The novel coronavirus, SARS‐CoV‐2, causes the unfathomable pandemic in the history of humankind. Bangladesh is also a victim of this critical situation. To investigate the genomic features of the pathogen, the first complete genome of the virus has very recently been published. Therefore, the long awaiting questions regarding the possible origin and typing of the strain(s) can now be answered. Here, we endeavor to mainly discuss the published reports or online‐accessed data (results) regarding those issues and presented a comprehensive picture of the typing of the virus alongside the probable origin of the sub‐clade containing Bangladeshi strain. Our observation suggested that this strain might have originated from the United Kingdom (UK) or other European countries epidemiologically linked to the UK. According to different genotyping classification schemes, this strain belongs to A2a clade under G major clade, is of B and/or L type, and is a SARS‐CoV‐2a sub‐strain. In the forwarding days, randomized genome data will certainly voluminate in Bangladesh, however because of globalization and immigrant movements, we urgently need a mass regional sequencing approach targeting the partial or complete genome that can link the epidemiological data and may help in further clinical interventions. This article is protected by copyright. All rights reserved.

Understanding the possible origin and genotyping of first Bangladeshi SARS‐CoV‐2 strain

Origin of SARS remains a mystery

One cannot spend more than 5 minutes on social media at the moment without finding a link to some conspiracy theory or other regarding the origin of SARS-CoV2, the coronavirus responsible for the COVID-19 pandemic. From the virus being deliberately released as a bioweapon, to pharmaceutical companies blocking the trials of natural remedies to boost their dangerous drugs and vaccines, the internet is rife with far-fetched rumour. And predictably, now that the first immunization trials have started, the anti-vaccine lobby have latched on to most of them. In the last week the trailer for a new 'bombshell documentary' Plandemic has been doing the rounds, gaining notoriety for being repeatedly removed from YouTube and Facebook. We usually wouldn't pay much heed to such things, but for retrovirologists like us the name associated with these claims is unfortunately too familiar: Dr Judy Mikovits.

FAKE SCIENCE: XMRV, COVID-19 AND THE TOXIC LEGACY OF DR JUDY MIKOVITS.

The initial cases of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) occurred in Wuhan, China, in December 2019 and swept the world by 23 June 2020 with 8 993 659 active cases, 469 587 deaths across 216 countries, areas or territories. This strongly implies global transmission occurred before the lockdown of China. However, the initial source's transmission routes of SARS‐CoV‐2 remain obscure and controversial. Research data suggest bat (RaTG13) and pangolin carried CoV were the proximal source of SARS‐CoV‐2. In this study, we used systematic phylogenetic analysis of Coronavirinae subfamily along with wild type human SARS‐CoV, MERS‐CoV, and SARS‐CoV‐2 strains. The key residues of the receptor‐binding domain (RBD) and O‐linked glycan were compared. SARS‐CoV‐2 strains were clustered with RaTG13 (97.41% identity), Pangolin‐CoV (92.22% identity) and Bat‐SL‐CoV (80.36% identity), forms a new clade‐2 in lineage B of beta‐CoV. The alignments of RBD contact residues to ACE2 justified? Those SARS‐CoV‐2 strains sequences were 100% identical by each other, significantly varied in RaTG13 and pangolin‐CoV. SARS‐CoV‐2 has a polybasic cleavage site with an inserted sequence of PRRA compared to RaTG13 and only PRR to pangolin. Only serine (Ser) in pangolin and both threonine (Thr) and serine (Ser) O‐linked glycans were seen in RaTG13, suggesting that a detailed study needed in pangolin (Manis javanica) and bat (Rhinolophus affinis) related CoV.

An update on the origin of SARS‐CoV‐2: Despite closest identity, bat (RaTG13) and pangolin derived coronaviruses varied in the critical binding site and O‐linked glycan residues

Since the early 2000s, three novel zooanthroponous coronaviruses (Betacoronavirus) have emerged. The first outbreak of infection (SARS) caused by SARS-CoV virus occurred in the fall of 2002 in China (Guangdong Province). A second outbreak (MERS) associated with the new MERS-CoV virus appeared in Saudi Arabia in autumn 2012. The third epidemic, which turned into a COVID-19 pandemic caused by SARS-CoV-2 virus, emerged in China (Hubei Province) in the autumn 2019. This review focuses on ecological and genetic aspects that lead to the emergence of new human zoanthroponous coronaviruses. The main mechanism of adaptation of zoonotic betacoronaviruses to humans is to changes in the receptor-binding domain of surface protein (S), as a result of which it gains the ability to bind human cellular receptors of epithelial cells in respiratory and gastrointestinal tract. This process is caused by the high genetic diversity and variability combined with frequent recombination, during virus circulation in their natural reservoir - bats (Microchiroptera, Chiroptera). Appearance of SARS-CoV, SARS-CoV-2 (subgenus Sarbecovirus), and MERS (subgenus Merbecovirus) viruses is a result of evolutionary events occurring in bat populations with further transfer of viruses to the human directly or through the intermediate vertebrate hosts, ecologically connected with bats. This review is based on the report at the meeting «Coronavirus - a global challenge to science¼ of the Scientific Council «Life Science¼ of the Russian Academy of Science: Lvov D.K., Alkhovsky S.V., Burtseva E.I. COVID-19 pandemic sources: origin, biology and genetics of coronaviruses of SARS-CoV, SARS-CoV-2, MERS-CoV (Conference hall of Presidium of RAS, 14 Leninsky Prospect, Moscow, Russia. April 16, 2020).

Bats have been recognized as the natural reservoirs of a large variety of viruses. Special attention has been paid to bat coronaviruses as the two emerging coronaviruses which have caused unexpected human disease outbreaks in the 21st century, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV), are suggested to be originated from bats. Various species of horseshoe bats in China have been found to harbor genetically diverse SARS-like coronaviruses. Some strains are highly similar to SARS-CoV even in the spike protein and are able to use the same receptor as SARS-CoV for cell entry. On the other hand, diverse coronaviruses phylogenetically related to MERS-CoV have been discovered worldwide in a wide range of bat species, some of which can be classified to the same coronavirus species as MERS-CoV. Coronaviruses genetically related to human coronavirus 229E and NL63 have been detected in bats as well. Moreover, intermediate hosts are believed to play an important role in the transmission and emergence of these coronaviruses from bats to humans. Understanding the bat origin of human coronaviruses is helpful for the prediction and prevention of another pandemic emergence in the future.

Bat origin of human coronaviruses

OBJECTIVE: COVID-19 has recently become a pandemic affecting many countries worldwide. This study aims to evaluate the current status of COVID-19 in Taiwan and analyze the source of infection. METHODS: National data regarding SARS-CoV-2 infection were obtained from Taiwan. CDC at the end of April 2020. These data were subjected to analysis of the current status and correlation between indigenous and imported COVID-19 cases. A phylogenetic tree was created to analyze the phylogeny of Taiwanese SARS-CoV-2 isolates. RESULTS: The first case of SARS-CoV-2 infection in Taiwan was detected on January 21, 2020. Epidemiological data indicate that by April 30, there were a total of 429 COVID-19 confirmed cases with the death rate of 1.3%. Most cases were identified as imported (79.9%; 343/429), with the majority originating from the United States of America (22.1%) and the United Kingdom (17.6%). Results from phylogenetic tree analyses indicate that the Taiwanese SARS-CoV-2 isolates were clustered with the SARS-CoV-2 isolates from other countries (bootstrap value 98%) and sub-clustered with bat SARS-like coronaviruses (bootstrap value 99%). CONCLUSION: This study suggests that the importation of SARS-CoV-2 infection was the primary risk-factor resulting in the COVID-19 epidemic in Taiwan.

Importation of SARS-CoV-2 infection leads to major COVID-19 epidemic in Taiwan

SARS-CoV-2, a new coronavirus strain responsible for COVID-19 has emerged in Wuhan City, China and still continuing its worldwide pandemic nature. Considering the severity of the disease, a number of studies are underway, and full genomic sequences have already been released in the last few weeks to enable the understanding of the evolutionary origin and molecular characteristics of this virus. Bioinformatics analysis, satellite derived imaging data and epidemiological attributes were employed to investigate origin, immunogenic resemblance and global threat of newly pandemic SARS-CoV-2 including Bangladesh perspective. Based on currently available genomic information, a phylogeny study was employed focusing four types of representative viral proteins (spike, membrane, envelope and nucleoprotein) of SARS-CoV-2, HCoV-229E, HCoV-OC43, SARS-CoV, HCoV-NL63, HKU1, MERS-CoV, HKU4, HKU5 and BufCoV-HKU26. The findings clearly demonstrated that SARS-CoV-2 exhibited evolutionary convergent relation with previously reported SARS-CoV. It was also found that SARS-CoV-2 proteins were highly similar and identical to SARS-CoV proteins, though proteins from other coronaviruses showed lower level of similarity and identical patterns. The cross-checked conservancy analysis of SARS-CoV-2 antigenic epitopes showed significant conservancy with antigenic epitopes derived from SARS-CoV. The study also prioritized the temperature comparison through satellite imaging alongside compiling and analyzing the epidemiological outbreak information on the 2019 novel coronavirus based on several open datasets on COVID-19 (SARS-CoV-2) and discussed possible threats to Bangladesh.

Ancestral origin, antigenic resemblance and epidemiological insights of novel coronavirus (SARS-CoV-2): Global burden and Bangladesh perspective

The fast-growing outbreak of the 2019 novel coronavirus (2019-nCoV), which originated from Wuhan locating in central China at the end of 2019, spread to multiple cities in merely a month. Although the mortality of this disease was lower than that of SARS, the incredible contagiousness was much higher than SRAS-CoV. Because of the tremendous clout of 2019-nCoV, it is essential to hold more details about it and monitor its future evolution. This mini review consequently summarizes the key elements of epidemiology features, providing updated relevant findings and novel insights related to 2019-nCoV.

Epidemiological Features of the 2019 Novel Coronavirus Outbreak in China

Results of analysis of phylogenetic, virological, epidemiological, ecological, clinical data of COVID-19 outbreaks in Wuhan, China (PRC) in comparison with SARS-2002 and MERS-2012 outbreaks allow to conclude: - the etiological agent of COVID-19 is coronavirus (2019-CoV), phylogenetically close to the SARS-CoV, isolated from human, and SARS-related viruses isolated from bats (SARS-related bat CoV viruses). These viruses belong to the Sarbecovirus subgenus, Betacoronavirus genus, Orthocoronavirinae subfamily, Coronaviridae family (Cornidovirinea: Nidovirales). COVID-19 is a variant of SARS-2002 and is different from MERS-2012 outbreak, which were caused by coronavirus belonged to the subgenus Merbecovirus of the same genus; - according to the results of phylogenetic analysis of 35 different betacoronaviruses, isolated from human and from wild animals in 2002-2019, the natural source of COVID-19 and SARS-CoV (2002) is bats of Rhinolophus genus (Rhinolophidae) and, probably, some species of other genera. An additional reservoir of the virus could be an intermediate animal species (snakes, civet, hedgehogs, badgers, etc.) that are infected by eating of infected bats. SARS-like coronaviruses circulated in bats in the interepidemic period (2003-2019); - seasonal coronaviruses (subgenus Duvinacovirus, Alphacoronavirus) are currently circulating (November 2019 - January 2020) in the European part of Russia, Urals, Siberia and the Far East of Russia, along with the influenza viruses A(H1N1)pdm09, A(H3N2), and В, as well as six other respiratory viruses (HPIV, HAdV, HRSV, HRV, HBoV, and HMPV).

[Etiology of epidemic outbreaks COVID-19 on Wuhan, Hubei province, Chinese People Republic associated with 2019-nCoV (Nidovirales, Coronaviridae, Coronavirinae, Betacoronavirus, Subgenus Sarbecovirus): lessons of SARS-CoV outbreak.]

The COVID-19 global pandemic is not even over yet but it has already taught us a lot of lessons - the hard way. The vast majority of the global community has blamed the Chinese Illegal wildlife markets for the origin of this pandemic. Through careful scientific analysis, I have explained in this article that we don't need such wildlife markets for these kinds of outbreaks to occur in the future. I have also explained how India which is the second-most populous country in the world, could be the origin of the next outbreak, even though such wildlife markets are either very rare or do not exist at all in India.

Could India be the origin of next COVID-19 like epidemic?

The positive-strand RNA viruses, severe acute respiratory syndrome coronavirus (SARS-CoV) and recently emerged COVID-19 epidemics, demonstrated the transmission capability of the coronaviruses by crossing the species barrier and emergence in humans. The source of coronavirus disease 2019 (COVID-19) is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), firstly reported in December 2019 at Wuhan, China. COVID-19 is a kind of viral pneumonia. The outbreak of SARS-CoV-2 (COVID-19) has been reported as the introduction of the third highly pathogenic coronavirus which crossed the species barrier and spread into the human population. Severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV) were the first two epidemic viruses, respectively, in the twenty-first century. Introduction of the 2019 novel coronaviruses (2019-nCoV) in human population is a worldwide concern, and this might have generated via RNA recombination among the previous reported coronaviruses. The COVID-19 is spreading in an alarming rate, and till date no vaccine or specific medicines are available in the market. The newly emerged coronavirus COVID-19 is strongly related to SARS-CoV except little dissimilarity. In this chapter, we will discuss about the alterations and variations in antigenicity, structural changes, and RNA recombination which might be responsible for the COVID-19 emergence.

Emergence and Reemergence of Severe Acute Respiratory Syndrome (SARS) Coronaviruses

A novel coronavirus, probably of bat origin, has caused an outbreak of severe respiratory infection in humans in Wuhan, China and has been dispersed globally by travelers. The WHO has declared the spread of the infection a Public Health Emergency of International Concern.

Travellers give wings to novel coronavirus (2019-nCoV)

Results of analysis of phylogenetic, virological, epidemiological, ecological, clinical data of COVID-19 outbreaks in Wuhan, China (PRC) in comparison with SARS-2002 and MERS-2012 outbreaks allow to conclude: - the etiological agent of COVID-19 is coronavirus (2019-CoV), phylogenetically close to the SARS-CoV, isolated from human, and SARS-related viruses isolated from bats (SARS-related bat CoV viruses). These viruses belong to the Sarbecovirus subgenus, Betacoronavirus genus, Orthocoronavirinae subfamily, Coronaviridae family (Cornidovirinea: Nidovirales). COVID-19 is a variant of SARS-2002 and is different from MERS-2012 outbreak, which were caused by coronavirus belonged to the subgenus Merbecovirus of the same genus; - according to the results of phylogenetic analysis of 35 different betacoronaviruses, isolated from human and from wild animals in 2002-2019, the natural source of COVID-19 and SARS-CoV (2002) is bats of Rhinolophus genus (Rhinolophidae) and, probably, some species of other genera. An additional reservoir of the virus could be an intermediate animal species (snakes, civet, hedgehogs, badgers, etc.) that are infected by eating of infected bats. SARS-like coronaviruses circulated in bats in the interepidemic period (2003-2019); - seasonal coronaviruses (subgenus Duvinacovirus, Alphacoronavirus) are currently circulating (November 2019 - January 2020) in the European part of Russia, Urals, Siberia and the Far East of Russia, along with the influenza viruses A(H1N1)pdm09, A(H3N2), and Ð, as well as six other respiratory viruses (HPIV, HAdV, HRSV, HRV, HBoV, and HMPV).

In December 2019 a new human coronavirus emerged in Wuhan, China, which is known as SARS-CoV‑2. The clinical course of the disease known as coronavirus disease 2019 (COVID-19) ranges from mild respiratory symptoms to severe lung failure. The virus is currently rapidly spreading around the world and pushing health systems to the limits of their capacity due to the exponential increase in the number of cases. The origin of SARS-CoV‑2 lies in the bat coronavirus pool and has now emerged in the human population due to interspecies transmission. Molecular diagnostic methods have been established in a very short time and a number of clinical studies on the effectiveness of different antiviral drugs are ongoing. The development of a vaccine using different approaches is also under investigation. Considering the high number of cases and mortality rates of up to 9% there is an urgent need for action. This article summarizes the current state of knowledge on human coronaviruses with a strong focus on the current data on SARS-CoV‑2. Due to the daily changing level of knowledge, the article reflects the status up to 21 March 2020.

Coronaviren: von der banalen Erkältung zum schweren Lungenversagen: Chronologie einer Pandemie

Abstract Objective COVID-19 has recently become a pandemic affecting many countries worldwide. This study aims to evaluate current status of COVID-19 in Taiwan and analyze the source of infection. Methods National data regarding SARS-CoV-2 infection were obtained from Taiwan CDC at the end of April, 2020. These data were subjected for analysis of the current status and correlation between indigenous and imported COVID-19 cases. Phylogenetic tree was performed to analyze the phylogeny of Taiwanese SARS-CoV-2 isolates. Results The initial case of SARS-CoV-2 infection in Taiwan was detected on January 21, 2020. Epidemiological data indicate that by April 30, there were a total of 429 COVID-19 confirmed cases with the death rate of 1.3%. Most of cases were identified as imported (79.9%; 343/429) with majority transmitted from United States of America (22.1%) and United Kingdom (17.6%). Results from phylogenetic tree analyses indicate that the Taiwanese SARS-CoV-2 isolates were clustered with the SARS-CoV-2 isolates from other countries (bootstrap value 98%) and sub-clustered with bat SARS-like coronaviruses (bootstrap value 99%). Conclusion This study suggests that importation of SARS-CoV-2 infection was the primary risk-factor resulting in the COVID-19 epidemic in Taiwan.

One cannot spend >5 min on social media at the moment without finding a link to some conspiracy theory or other regarding the origin of SARS-CoV2, the coronavirus responsible for the COVID-19 pandemic. From the virus being deliberately released as a bioweapon to pharmaceutical companies blocking the trials of natural remedies to boost their dangerous drugs and vaccines, the Internet is rife with far-fetched rumors. And predictably, now that the first immunization trials have started, the antivaccine lobby has latched on to most of them. In the last week, the trailer for a new "bombshell documentary" Plandemic has been doing the rounds, gaining notoriety for being repeatedly removed from YouTube and Facebook. We usually would not pay much heed to such things, but for retrovirologists like us, the name associated with these claims is unfortunately too familiar: Dr. Judy Mikovits.

Fake Science: XMRV, COVID-19, and the Toxic Legacy of Dr. Judy Mikovits

Middle East respiratory syndrome (MERS) is an emerging infectious disease, caused by Middle East respiratory syndrome coronavirus (MERS-CoV) and is considered to be a zoonosis. However, the natural reservoirs of MERS-CoV remain obscure, with bats and camels as the most suspected sources. In this article, we review the evidence supporting a bat/camel origin of human MERS-CoV infection and current knowledge on the modes of camel-to-human transmission of MERS-CoV.

Evidence for zoonotic origins of Middle East respiratory syndrome coronavirus

The ongoing Coronavirus Disease 2019 (COVID-19) outbreak, originated in the end of 2019 in Wuhan, China, has claimed more than 2200 lives and posed a huge threat to global public health. The Chinese government has implemented control measures including setting up special hospitals and travel restriction to mitigate the spread. We propose conceptual models for the outbreak in Wuhan with the consideration of individual behavioural reaction and governmental actions, e.g., holiday extension, travel restriction, hospitalisation and quarantine. We employed the estimates of these two key components from the 1918 influenza pandemic in London, United Kingdom, incorporated zoonotic introductions and the emigration, then computed future trends and the reporting ratio. The model is concise in structure, and it successfully captures the course of the COVID-19 outbreak, and thus sheds light on understanding the trends of the outbreak.

A conceptual model for the outbreak of Coronavirus disease 2019 (COVID-19) in Wuhan, China with individual reaction and governmental action

Ideas and the origin of evidence during the COVID-19 pandemic.

The human pathogen severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the major pandemic of the 21st century. We analyzed >4,700 SARS-CoV-2 genomes and associated meta-data retrieved from public repositories. SARS-CoV-2 sequences have a high sequence identity (>99.9%), which drops to >96% when compared to bat coronavirus. We built a mutation-annotated reference SARS-CoV-2 phylogeny with two main macro-haplogroups, A and B, both of Asian origin, and >160 sub-branches representing virus strains of variable geographical origins worldwide, revealing a uniform mutation occurrence along branches that could complicate the design of future vaccines. The root of SARS-CoV-2 genomes locates at the Chinese haplogroup B1, with a TMRCA dating to 12 November 2019 - thus matching epidemiological records. Sub-haplogroup A2a originates in China and represents the major non-Asian outbreak. Multiple founder effect episodes, most likely associated with super-spreader hosts, explain COVID-19 pandemic to a large extent.

The impact of super-spreaders in COVID-19: mapping genome variation worldwide

Severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) are two highly transmissible and pathogenic viruses that emerged in humans at the beginning of the 21st century. Both viruses likely originated in bats, and genetically diverse coronaviruses that are related to SARS-CoV and MERS-CoV were discovered in bats worldwide. In this Review, we summarize the current knowledge on the origin and evolution of these two pathogenic coronaviruses and discuss their receptor usage; we also highlight the diversity and potential of spillover of bat-borne coronaviruses, as evidenced by the recent spillover of swine acute diarrhoea syndrome coronavirus (SADS-CoV) to pigs.

Origin and evolution of pathogenic coronaviruses

A newly emerged coronavirus, SARS-CoV-2, caused severe outbreaks of pneumonia in China in December 2019 and has since spread to various countries around the world. To probe the origin and transmission dynamics of this virus, we performed phylodynamic analysis of 247 high quality genomic sequences of viruses available in the GISAID platform as of March 05, 2020. A substantial number of earliest sequences reported in Wuhan in December 2019, including those of viruses recovered from the Huanan Seafood Market (HNSM), the site of the initial outbreak, were genetically diverse, suggesting that viruses of multiple sources were involved in the original outbreak. The viruses were subsequently disseminated to different parts of China and other countries, with diverse mutational profiles being recorded in strains recovered subsequently. Interestingly, four genetic clusters defined as Super-transmitters (STs) were found to become dominant and were responsible for the major outbreaks in various countries. Among the four clusters, ST1 is widely disseminated in Asia and the US and mainly responsible for outbreaks in the states of Washington and California in the US as well as those in South Korea at the end of February and early March, whereas ST4 contributed to the pandemic in Europe. Each ST cluster carried a signature mutation profile which allowed us to trace the origin and transmission patterns of specific viruses in different parts of the world. Using the signature mutations as markers of STs, we further analysed 1539 genome sequences reported after February 29, 2020. We found that around 90% of these genomes belonged to STs with ST4 being the dominant one and their contribution to pandemic in different continents were also depicted. The identification of these super-transmitters provides insight into the control of further transmission of SARS-CoV-2.

Identification of super-transmitters of SARS-CoV-2

Since December 2019, coronavirus disease 2019 (COVID-19) emerged in Wuhan, Central China and rapidly spread throughout China. Up to March 3, 2020, SARS-CoV-2 has infected more than 89,000 people in China and other 66 countries across six continents. In this study, we used 10 new sequenced genomes of SARS-CoV-2 and combined 136 genomes from GISAID database to investigate the genetic variation and population demography through different analysis approaches (e.g. Network, EBSP, Mismatch, and neutrality tests). The results showed that 80 haplotypes had 183 substitution sites, including 27 parsimony-informative and 156 singletons. Sliding window analyses of genetic diversity suggested a certain mutations abundance in the genomes of SARS-CoV-2, which may be explaining the existing widespread and high adaptation of the deadly virus. Phylogenetic analysis showed that the view, pangolin acted as an intermediate host, may be controversial. The network indicated that, in the original haplotype (H14), one patient sample lived near the Huanan seafood market (approximate 2 km), indicating high possibility of the patient having a history of unconscious contact with this market. However, based on this clue, we cannot accurately concluded that whether this market was the origin center of SARS-CoV-2. Additionally, 16 genomes, collected from this market, assigned to 10 haplotypes, indicated a circulating infection within the market in a short term and then leading to the outbreak of SARS-CoV-2 in Wuhan and other areas. The EBSP results showed that the first estimated expansion date of SARS-CoV-2 began from 7 December 2019, which may indicated that the transmission could have begun from person to person in mid to late November.

Genome-wide data inferring the evolution and population demography of the novel pneumonia coronavirus (SARS-CoV-2)

Coronaviruses are the well-known cause of severe respiratory, enteric and systemic infections in a wide range of hosts including man, mammals, fish, and avian. The scientific interest on coronaviruses increased after the emergence of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) outbreaks in 2002-2003 followed by Middle East Respiratory Syndrome CoV (MERS-CoV). This decade's first CoV, named 2019-nCoV, emerged from Wuhan, China, and declared as 'Public Health Emergency of International Concern' on January 30th, 2020 by the World Health Organization (WHO). As on February 4, 2020, 425 deaths reported in China only and one death outside China (Philippines). In a short span of time, the virus spread has been noted in 24 countries. The zoonotic transmission (animal-to-human) is suspected as the route of disease origin. The genetic analyses predict bats as the most probable source of 2019-nCoV though further investigations needed to confirm the origin of the novel virus. The ongoing nCoV outbreak highlights the hidden wild animal reservoir of the deadly viruses and possible threat of spillover zoonoses as well. The successful virus isolation attempts have made doors open for developing better diagnostics and effective vaccines helping in combating the spread of the virus to newer areas.

Emerging novel coronavirus (2019-nCoV)-current scenario, evolutionary perspective based on genome analysis and recent developments

The Coronavirus pandemic (COVID-19) is one of the most devastating in this century. It originated in China in December 2019 caused by the SARS-Cov-2 virus, and in less than a month it had been classified as an "International Public Health Emergency". To date there are nearly 3 million people infected and more than 250,000 deaths caused by the disease worldwide. Initially it affects the respiratory tract with atypical pneumonia and in severe cases it produces systemic inflammation with cytokine storm that can cause rapid deterioration with circulatory and respiratory failure, coagulopathy and a lethality rate of approximately 7%. In Mexico, the first case was detected in February 2020, and to date there are 26,616 confirmed cases and 2,961 deaths throughout the country. The low number of diagnostic tests conducted in our country clearly underestimates the real incidence and impact of the disease. The most affected groups are those with risk factors such as age over 60, presence of hypertension, diabetes or cardiovascular disease. Of the confirmed cases, 15% are healthcare workers. There is no specific treatment or vaccine yet, so it is important to have hygiene, social isolation and personal protection measures. Health, social and economic consequences could have great impact in the near future.

The SARS-CoV-2 (COVID-19) coronavirus pandemic: current situation and implications for Mexico.

Ideas and the origin of evidence during the COVID-19 pandemic

This communication aims to advocate a more coordinate activity mainly between medical and environmental scientists to clarify some confusing information related to airborne diffusion mechanisms of COVID-19. In this frame it is suggested that parameters other than environmental pollution (accounting for pollution-to-human transmission mechanisms), as for example parameters involving commercial exchanges (accounting for human-to-human transmission mechanisms), should be considered to better justify the difference in the initial diffusion of virus in Italy.

Commercial exchanges instead of air pollution as possible origin of COVID-19 initial diffusion phase in Italy: More efforts are necessary to address interdisciplinary research

There are outstanding evolutionary questions on the recent emergence of coronavirus SARS-CoV-2/hCoV-19 in Hubei province that caused the COVID-19 pandemic, including (1) the relationship of the new virus to the SARS-related coronaviruses, (2) the role of bats as a reservoir species, (3) the potential role of other mammals in the emergence event, and (4) the role of recombination in viral emergence. Here, we address these questions and find that the sarbecoviruses – the viral subgenus responsible for the emergence of SARS-CoV and SARS-CoV-2 – exhibit frequent recombination, but the SARS-CoV-2 lineage itself is not a recombinant of any viruses detected to date. In order to employ phylogenetic methods to date the divergence events between SARS-CoV-2 and the bat sarbecovirus reservoir, recombinant regions of a 68-genome sarbecovirus alignment were removed with three independent methods. Bayesian evolutionary rate and divergence date estimates were consistent for all three recombination-free alignments and robust to two different prior specifications based on HCoV-OC43 and MERS-CoV evolutionary rates. Divergence dates between SARS-CoV-2 and the bat sarbecovirus reservoir were estimated as 1948 (95% HPD: 1879-1999), 1969 (95% HPD: 1930-2000), and 1982 (95% HPD: 1948-2009). Despite intensified characterization of sarbecoviruses since SARS, the lineage giving rise to SARS-CoV-2 has been circulating unnoticed for decades in bats and been transmitted to other hosts such as pangolins. The occurrence of a third significant coronavirus emergence in 17 years together with the high prevalence and virus diversity in bats implies that these viruses are likely to cross species boundaries again. In Brief The Betacoronavirus SARS-CoV-2 is a member of the sarbecovirus subgenus which shows frequent recombination in its evolutionary history. We characterize the extent of this genetic exchange and identify non-recombining regions of the sarbecovirus genome using three independent methods to remove the effects of recombination. Using these non-recombining genome regions and prior information on coronavirus evolutionary rates, we obtain estimates from three approaches that the most likely divergence date of SARS-CoV-2 from its most closely related available bat sequences ranges from 1948 to 1982. Key Points RaTG13 is the closest available bat virus to SARS-CoV-2; a sub-lineage of these bat viruses is able to infect humans. Two sister lineages of the RaTG13/SARS-CoV-2 lineage infect Malayan pangolins. The sarbecoviruses show a pattern of deep recombination events, indicating that there are high levels of co-infection in horseshoe bats and that the viral pool can generate novel allele combinations and substantial genetic diversity; the sarbecoviruses are efficient ‘explorers’ of phenotype space. The SARS-CoV-2 lineage is not a recent recombinant, at least not involving any of the bat or pangolin viruses sampled to date. Non-recombinant regions of the sarbecoviruses can be identified, allowing for phylogenetic inference and dating to be performed. We constructed three such regions using different methods. We estimate that RaTG13 and SARS-CoV-2 diverged 40 to 70 years ago. There is a diverse unsampled reservoir of generalist viruses established in horseshoe bats. While an intermediate host responsible for the zoonotic event cannot be ruled out, the relevant evolution for spillover to humans very likely occurred in horseshoe bats.

Evolutionary origins of the SARS-CoV-2 sarbecovirus lineage responsible for the COVID-19 pandemic

The spread of SARS-CoV-2 since December 2019 has become a pandemic and impacted many aspects of human society. Here, we analyzed genetic variation of SARS-CoV-2 and its related coronavirus and found the evidence of intergenomic recombination. After correction for mutational bias, analysis of 137 SARS-CoV-2 genomes as of 2/23/2020 revealed the excess of low frequency mutations on both synonymous and nonsynonymous sites which is consistent with recent origin of the virus. In contrast to adaptive evolution previously reported for SARS-CoV in its brief epidemic in 2003, our analysis of SARS-CoV-2 genomes shows signs of relaxation of selection. The sequence similarity of the spike receptor binding domain between SARS-CoV-2 and a sequence from pangolin is probably due to an ancient intergenomic introgression. Therefore, SARS-CoV-2 might have cryptically circulated within humans for years before being recently noticed. Data from the early outbreak and hospital archives are needed to trace its evolutionary path and reveal critical steps required for effective spreading. Two mutations, 84S in orf8 protein and 251V in orf3 protein, occurred coincidentally with human intervention. The 84S first appeared on 1/5/2020 and reached a plateau around 1/23/2020, the lockdown of Wuhan. 251V emerged on 1/21/2020 and rapidly increased its frequency. Thus, the roles of these mutations on infectivity need to be elucidated. Genetic diversity of SARS-CoV-2 collected from China was two time higher than those derived from the rest of the world. In addition, in network analysis, haplotypes collected from Wuhan city were at interior and have more mutational connections, both of which are consistent with the observation that the outbreak of cov-19 was originated from China. SUMMARY In contrast to adaptive evolution previously reported for SARS-CoV in its brief epidemic, our analysis of SARS-CoV-2 genomes shows signs of relaxation of selection. The sequence similarity of the spike receptor binding domain between SARS-CoV-2 and a sequence from pangolin is probably due to an ancient intergenomic introgression. Therefore, SARS-CoV-2 might have cryptically circulated within humans for years before being recently noticed. Data from the early outbreak and hospital archives are needed to trace its evolutionary path and reveal critical steps required for effective spreading. Two mutations, 84S in orf8 protein and 251V in orf3 protein, occurred coincidentally with human intervention. The 84S first appeared on 1/5/2020 and reached a plateau around 1/23/2020, the lockdown of Wuhan. 251V emerged on 1/21/2020 and rapidly increased its frequency. Thus, the roles of these mutations on infectivity need to be elucidated.

The origin and underlying driving forces of the SARS-CoV-2 outbreak

The ongoing pandemic of a new human coronavirus, SARS-CoV-2, has generated enormous global concern. We and others in China were involved in the initial genome sequencing of the virus. Herein, we describe what genomic data reveal about the emergence SARS-CoV-2 and discuss the gaps in our understanding of its origins.

A Genomic Perspective on the Origin and Emergence of SARS-CoV-2

In early December 2019, the 2019 novel coronavirus (COVID-19) was identified as the agent responsible for the first pneumonia cases of unknown origin in Wuhan, the capital of the Hubei region in China. The virus has been identified as a novel enveloped RNA betacoronavirus2 , that has been promptly named SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). The World Health Organization (WHO), on January 12, 2020 declared the COVID-19 a public health emergency of international concern. On March 11, the WHO made the assessment that COVID-19 can be characterized as a pandemic.

Papa Giovanni XXIII Bergamo Hospital at the time of the COVID-19 outbreak: letter from the warfront.

In December, 2019, an infection outbreak occurred in Wuhan of unknown cause, which attracts intense attention. Shortly after the virus was identified with the name of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), the epidemic of coronavirus disease 2019 (COVID-19) broke out and an information storm occurred. At that time, two important aspects: the stage and the links of epidemic, were unclear. Answers to the questions, what are the sources, how do infections occur, and who will be affected should be clarified as the outbreak continues to evolve. Furthermore, the epidemic process and the stage of epidemic should be explored and discussed. Based on information of SARS, middle east respiratory syndrome(MERS) and COVID-19, the links of epidemic (the sources, the routes of infection, and the susceptible population) will be discussed as well as the role of the natural and the social factors. Epidemiology characteristics of patients will be traced based on current information.

Epidemiology of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2.

According to what was published by the WHO (World Health Organization), a first case of acute respiratory infection, of unknown origin, appeared in the province of HUBEI, CHINA, in the city of WUHAN, (December 2019). After having ruled out other etiological agents, the isolation of a new coronavirus (7-01-2020) was achieved, which was called new coronavirus (nCOV, COVID-19), currently named SARS-CoV-2. Coronaviruses, being important pathogens, can infect the respiratory, gastrointestinal, hepatic, and nervous systems of humans and birds, livestock, bats, mice, and other wild animals. Since the outbreaks of SARS (Severe Acute Respiratory Syndrome) in 2002 and MERS (Middle East Respiratory Syndrome) in 2012, the transmission of these viruses between humans and animals has been demonstrated.

Coronavirus-2019. General considerations/ Coronavirus-2019. Consideraciones Generales

Exploring the presence of animal origin in the causation of corona virus disease 2019 outbreak and strategies to prevent acquisition of the infection

Exploring the Presence of Animal Origin in the Causation of Corona Virus Disease 2019 Outbreak and Strategies to Prevent Acquisition of the Infection

A novel Coronavirus, 2019-nCoV, has been identified as the causal pathogen of an ongoing epidemic, with the first cases reported in Wuhan, China, last December 2019, and has since spread to other countries worldwide, included Europe and very recently Italy. In this short report, phylogenetic reconstruction was used to better understand the transmission dynamics of the virus from its first introduction in China focusing on the more recent evidence of infection in a couple of Chinese tourists arrived in Italy on 23rd January 2020 and labeled as Coronavirus Italian cases. A maximum clade credibility tree has been built using a dataset of 54 genome sequences of 2019-nCoV plus two closely related bat strains (SARS-like CoV) available in GenBank. Bayesian time-scaled phylogenetic analysis was implemented in BEAST 1.10.4. The Bayesian phylogenetic reconstruction showed that 2019-2020 nCoV firstly introduced in Wuhan on 25 November 2019, started epidemic transmission reaching many countries worldwide, including Europe and Italy where the two strains isolated dated back 19 January 2020, the same that the Chinese tourists arrived in Italy. Strains isolated outside China were intermixed with strains isolated in China as evidence of likely imported cases in Rome, Italy, and Europe, as well. In conclusion, this report suggests that further spread of 2019-nCoV epidemic was supported by human mobility and that quarantine of suspected or diagnosed cases is useful to prevent further transmission. Viral genome phylogenetic analysis represents a useful tool for the evaluation of transmission dynamics and preventive action.

The first two cases of 2019-nCoV in Italy: Where they come from?

This communication aims to advocate a more coordinate activity mainly between medical and environmental scientists to clarify some confusing information related to airborne diffusion mechanisms of COVID-19. In this frame it is suggested that parameters other than environmental pollution (accounting for pollution-to human transmission mechanisms), as for example parameters involving commercial exchanges (accounting for human-to human transmission mechanisms), should be considered to better justify the difference in the initial diffusion of virus in Italy.

Commercial exchanges instead of air pollution as possible origin of COVID-19 initial diffusion phase in Italy: more efforts are necessary to address interdisciplinary research

A novel coronavirus (nCoV-2019) was the cause of an outbreak of respiratory illness detected in Wuhan, Hubei Province, China in December of 2019. Genomic analyses of nCoV-2019 determined a 96% resemblance with a coronavirus isolated from a bat in 2013 (RaTG13); however, the receptor binding motif (RBM) of these two genomes share low sequence similarity. This divergence suggests a possible alternative source for the RBM coding sequence in nCoV-2019. We identified high sequence similarity in the RBM between nCoV-2019 and a coronavirus genome reconstructed from a viral metagenomic dataset from pangolins possibly indicating a more complex origin for nCoV-2019.

Evidence of recombination in coronaviruses implicating pangolin origins of nCoV-2019

Research efforts of the ongoing SARS-CoV-2 pandemic have focused on viral genome sequence analysis to understand how the virus spread across the globe. Here, we assess three recently identified SARS-CoV-2 genomes in Beijing from June 2020 and attempt to determine the origin of these genomes, made available in the GISAID database. The database contains fully or partially sequenced SARS-CoV-2 samples from laboratories around the world. Including the three new samples and excluding samples with missing annotations, we analyzed 7, 643 SARS-CoV-2 genomes. Using principal component analysis computed on a similarity matrix that compares all pairs of the SARS-CoV-2 nucleotide sequences at all loci simultaneously, using the Jaccard index, we find that the newly discovered virus genomes from Beijing are in a genetic cluster that consists mostly of cases from Europe and South(east) Asia. The sequences of the new cases are most related to virus genomes from a small number of cases from China (March 2020), cases from Europe (February to early May 2020), and cases from South(east) Asia (May to June 2020). These findings could suggest that the original cases of this genetic cluster originated from China in March 2020 and were re-introduced to China by transmissions from samples from South(east) Asia between April and June 2020.

Unsupervised cluster analysis of SARS-CoV-2 genomes indicates that recent (June 2020) cases in Beijing are from a genetic subgroup that consists of mostly European and South(east) Asian samples, of which the latter are the most recent

Since the outbreak of severe acute respiratory syndrome (SARS) 18 years ago, a large number of SARS-related coronaviruses (SARSr-CoVs) have been discovered in their natural reservoir host, bats(1–4). Previous studies have shown that some bat SARSr-CoVs have the potential to infect humans(5–7). Here we report the identification and characterization of a new coronavirus (2019-nCoV), which caused an epidemic of acute respiratory syndrome in humans in Wuhan, China. The epidemic, which started on 12 December 2019, had caused 2,794 laboratory-confirmed infections including 80 deaths by 26 January 2020. Full-length genome sequences were obtained from five patients at an early stage of the outbreak. The sequences are almost identical and share 79.6% sequence identity to SARS-CoV. Furthermore, we show that 2019-nCoV is 96% identical at the whole-genome level to a bat coronavirus. Pairwise protein sequence analysis of seven conserved non-structural proteins domains show that this virus belongs to the species of SARSr-CoV. In addition, 2019-nCoV virus isolated from the bronchoalveolar lavage fluid of a critically ill patient could be neutralized by sera from several patients. Notably, we confirmed that 2019-nCoV uses the same cell entry receptor—angiotensin converting enzyme II (ACE2)—as SARS-CoV.

A pneumonia outbreak associated with a new coronavirus of probable bat origin

The global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causing coronavirus disease 2019 (COVID-19) reached over two million confirmed cases worldwide, and numbers are still growing at a fast rate. The majority of new infections are now being reported outside of China, where the outbreak officially originated in December 2019 in Wuhan. Despite the wide outbreak of the infection, a remarkable asymmetry is observed in the number of cases and in the distribution of the severity of the COVID-19 symptoms in patients with respect to the countries/regions. In the early stages of a new pathogen outbreak, it is critical to understand the dynamics of the infection transmission, in order to follow contagion over time and project the epidemiological situation in the near future. While it is possible to reason that observed variation in the number and severity of cases stem from the initial number of infected individuals, the difference in the testing policies and social aspects of community transmissions, the factors that could explain high discrepancy in areas with a similar level of healthcare still remain unknown. Here we introduce a binary classifier based on an artificial neural network that can help in explaining those differences and that can be used to support the design of containment policies. We propose that air pollutants, and specifically particulate matter (PM) 2.5 and ozone, are oppositely related with the SARS-CoV-2 infection frequency and could serve as surrogate markers to complement the infection outbreak anticipation.

Spatial-temporal variations of atmospheric factors contribute to SARS-CoV-2 outbreak

Since the outbreak of severe acute respiratory syndrome (SARS) 18 years ago, a large number of SARS-related coronaviruses (SARSr-CoVs) have been discovered in their natural reservoir host, bats1-4. Previous studies have shown that some bat SARSr-CoVs have the potential to infect humans5-7. Here we report the identification and characterization of a new coronavirus (2019-nCoV), which caused an epidemic of acute respiratory syndrome in humans in Wuhan, China. The epidemic, which started on 12 December 2019, had caused 2,794 laboratory-confirmed infections including 80 deaths by 26 January 2020. Full-length genome sequences were obtained from five patients at an early stage of the outbreak. The sequences are almost identical and share 79.6% sequence identity to SARS-CoV. Furthermore, we show that 2019-nCoV is 96% identical at the whole-genome level to a bat coronavirus. Pairwise protein sequence analysis of seven conserved non-structural proteins domains show that this virus belongs to the species of SARSr-CoV. In addition, 2019-nCoV virus isolated from the bronchoalveolar lavage fluid of a critically ill patient could be neutralized by sera from several patients. Notably, we confirmed that 2019-nCoV uses the same cell entry receptor-angiotensin converting enzyme II (ACE2)-as SARS-CoV.

2019 novel coronavirus (SARS-CoV-2), which originated in Wuhan, China, has attracted the world's attention over the last month. The Chinese government has taken emergency measures to control the outbreak and has undertaken initial steps in the diagnosis and treatment of 2019 novel coronavirus infection disease (COVID-19). However, SARS-CoV-2 possesses powerful pathogenicity as well as transmissibility and still holds many mysteries that are yet to be solved, such as whether the virus can be transmitted by asymptomatic patients or by mothers to their infants. Our research presents selected available cases of COVID-19 in China to better understand the transmission and diagnosis regarding this infectious disease.

The transmission and diagnosis of 2019 novel coronavirus infection disease (COVID-19): A Chinese perspective

Since the identification of the first cases of the coronavirus in December 2019 in Wuhan, China, there has been a significant amount of confusion regarding the origin and spread of the so-called 'coronavirus', officially named SARS-CoV-2, and the cause of the disease COVID-19 Conflicting messages from the media and officials across different countries and organizations, the abundance of disparate sources of information, unfounded conspiracy theories on the origins of the newly emerging virus and the inconsistent public health measures across different countries, have all served to increase the level of anxiety in the population Where did the virus come from? How is it transmitted? How does it cause disease? Is it like flu? What is a pandemic? What can we do to stop its spread? Written by a leading expert, this concise and accessible introduction provides answers to the most common questions surrounding coronavirus for a general audience

Understanding Coronavirus

Epidemiology of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan city, China in December 2019 and thereafter its spillover across the world has created a global pandemic and public health crisis. Today, it appears as a threat to human civilization. Scientists and medical practitioners across the world are involved to trace out the origin and evolution of SARS-CoV-2 (also called 2019 novel coronavirus and referred as 2019-nCoV), its transmission route, cause of pathogenicity, and possible remedial action. In this work, we aim to find out the origin, evolutionary patternthat led to its pathogenicity and possible transmission pathway of 2019-nCoV. To achieve the aims we conducted a large-scale deep phylogenetic analysis on the 162 complete Orthocoronavirinae genomes consisting of four genera namely Alphacoronavirus, Betacoronavirus, Deltacoronavirus and Gammacoronavirus, their gene trees analysis and subsequently genome and gene recombination analyses. Our analyses revealed that i) bat, pangolin and anteater are the natural hosts of 2019-nCoV, ii) outbreak of 2019-nCoV took place via inter-intra species transmission mode, iii) host-specific adaptive mutation made 2019-nCoV more virulent, and the presence of widespread recombination events led to the evolution of new 2019-nCoV strain and/or could be determinant of its pathogenicity. Highlights Orthocoronavirinae genome phylogeny revealed that bat, pangolin and anteater are natural reservoir hosts of novel coronavirus (2019-nCoV/SARS-CoV-2). Host-specific adaptive mutation occurred among the coronaviruses. Transmission of 2019-nCoV to human took place by inter-intra species mode of transmission. Presence of widespread recombination events led to the evolution of new 2019-nCoV strain and/or could be determinant of its pathogenicity.

Deep phylogenetic analysis of Orthocoronavirinae genomes traces the origin, evolution and transmission route of 2019 novel coronavirus

Before the severe acute respiratory syndrome outbreak in 2003, coronaviruses (CoVs) were not considered to be highly pathogenic to humans. However, it was this epidemic that highlighted this group of viruses and included them among the causative agents of emerging epidemic diseases. In addition, in 2012, another new CoV responsible for the Middle East respiratory syndrome was identified. Both infections were considered a threat to global health security. At present, the third epidemic caused by a CoV is being faced. This new CoV, called 2019-nCoV, was originated in the city of Wuhan, China, and has been linked to severe respiratory infections in humans. Thanks to the collaboration of experts worldwide, more information about this virus and its infection is reported each day, which allows modifying the recommendations for its prevention and treatment, without forgetting that the ultimate goal is to control this epidemic. In this review, the important aspects of this new coronavirus, 2019-nCoV, and its disease, COVID-19, have been summarized with the information available up to February 2020.

COVID-19: The outbreak caused by a new coronavirus.

The emergence of an unusual Corona virus (COVID-19) flu pandemic starting in China in December 2019, spreading all around the globe is a major threat to public health The investigations have shown this virus originated from a seafood market in Wuhan However, the unavailability of medicines for the new disease is a big challenge all around An attempt has been made in the present article to familiarise about the morphology of the virus The study of effect of pH, temperature and relative humidity is also depicted Various preventive measures have also been discussed The natural dietary measures suggested in the paper would be very beneficial to improve and boost the immunity of the mankind

Study of Morphological Nature of Coronavirus: Causes and Prevention

To investigate the genetic diversity, time origin, and evolutionary history of the 2019‐nCoV outbreak in China and Thailand, a total of 12 genome sequences of the virus with known sampling date (24 December 2019 and 13 January 2020) and geographic location (primarily Wuhan city, Hubei Province, China, but also Bangkok, Thailand) were analyzed. Phylogenetic and likelihood‐mapping analyses of these genome sequences were performed. On the basis of our results, the star‐like signal and topology of 2019‐nCoV may be indicative of potentially large “first generation” human‐to‐human virus transmission. We estimated that 2019‐nCoV likely originated in Wuhan on 9 November 2019 (95% credible interval: 25 September 2019 and 19 December 2019), and that Wuhan is the major hub for the spread of the 2019‐nCoV outbreak in China and elsewhere. Our results could be useful for designing effective prevention strategies for 2019‐nCoV in China and beyond.

Potential of large “first generation” human‐to‐human transmission of 2019‐nCoV