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The 2019‐new coronavirus epidemic: Evidence for virus evolution - Coggle…
The 2019‐new coronavirus epidemic: Evidence
for virus evolution
Introduction
In 2019, the 2019-nCoV was reported to have originated in Wuhan, China. People infected with the virus were observed to possess a severe respiratory infection.
The first cause of infection seen in humans was believed to be caused by animal to human viral transmission.
The new coronavirus, named 2019-nCoV is from the Coronaviridae family and the Orthocoronavirinae subfamily.
The report will use a phylogenetic tree to infer more on the selective pressures inflicted onto the virus in specific regions.
Materials and Methods
Datasets were built using five SARS sequences that were similar to 2019-nCoV, two Middle East respiratory syndrome (MERS) sequences, and five bat SARS‐like coronavirus similar to 2019-nCoV.
By using the maximum likelihood (ML) method, it allowed for multiple phylogenetic hypotheses to be tested.
Fifteen complete genomes of 2019‐nCoV sequences were taken from the GISAID (
https://www.gisaid.org/
) and GenBank (
http://www.ncbi.nlm.nih.gov/genbank/
) online databases.
Other methods which involved the downloading of an adaptive evolution sever and the use of homology models were used to create and observe a phylogenetic tree of the 2019‐nCoV in specific regions.
The 2019-nCoV virus sequences were sampled in 4 specific locations: Wuhan, Zhejiang, Nonthaburi and Guangdong.
Results
Another distinct clade formed, and originating from the ancestor, is two branches of bat SARS-like virus sequences. One branch has several bat SARS-like sequences and the other branch possesses only one bat SARS-like sequence. Branching off from the one of the bat SARS-like virus sequences in the branch with multiple sequences is the SARS virus sequences.
From the branch of the single bat SARS-like virus sequence, the sampling locations of the 2019-nCoV virus sequences can be observed. This displays that the 2019-nCoV virus sequences are only closely related to one specific type of bat SARS-like virus sequence.
By observing the ML phylogenetic tree created in Figure 1 of the report, one can see how the MERS virus sequences have formed a distinct clade from the other viruses that are compared. This clade is shown to originate from an ancestor.
Discussion
The evidence presented in the paper supports the theory of animal to human viral transmission of the 2019-nCoV virus currently seen in humans.
Mutations observed in specific proteins found in the 2019-nCoV virus suggests two important characteristics of the 2019-nCoV virus during the epidemic: (1) the virus may have a higher ability to infect hosts and (2) the virus possesses increased pathogenicity when compared to the bat‐like SARS coronavirus, but the 2019-nCoV virus has decreased pathogenicity than SARS coronavirus.
The data reported in the paper illustrated that the 2019-nCoV was significantly connected to a specific sequence from the bat SARS‐like coronavirus which was isolated in
Rhinolophus sinicus
in China in the year 2015.
These characteristics displayed by the 2019-CoV virus may explain the zoonotic transference of the virus from animal-to-human.
Work cited
Benvenuto D, Giovanetti M, Ciccozzi A, Spoto S, Angeletti S, Ciccozzi M. 2020. The 2019-new coronavirus epidemic: evidence for virus evolution. Journ of Med Virol; 92(4):455-459.