Abstract
Over the past two decades, there have been two major outbreaks where the crossover of animal Betacoronaviruses to humans has resulted in severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). In December 2019, a global public health concern started with the emergence of a new strain of coronavirus (SARS-CoV-2 or 2019 novel coronavirus, 2019-nCoV) which has rapidly spread all over the world from its origin in Wuhan, China. SARS-CoV-2 belongs to the Betacoronavirus genus, which includes human SARS-CoV, MERS and two other human coronaviruses (HCoVs), HCoV-OC43 and HCoV-HKU1. The fatality rate of SARS-CoV-2 is lower than the two previous coronavirus epidemics, but it is faster spreading and the large number of infected people with severe viral pneumonia and respiratory illness, showed SARS-CoV-2 to be highly contagious. Based on the current published evidence, herein we summarize the origin, genetics, epidemiology, clinical manifestations, preventions, diagnosis and up to date treatments of SARS-CoV-2 infections in comparison with those caused by SARS-CoV and MERS-CoV. Moreover, the possible impact of weather conditions on the transmission of SARS-CoV-2 is also discussed. Therefore, the aim of the present review is to reconsider the two previous pandemics and provide a reference for future studies as well as therapeutic approaches.
Highlights
Comparative genome studies published in recent papers strongly support the bats and that pangolins (Manis javanica) acted as intermediate mammalian hosts hypothesis that SARS-CoV-2 originated in bats and that pangolins (Manis javanica) acted as the genetic sequence the SARS-CoV-2 more than 79%
RNA genome can be packaged into one adeno-associated virus (AAV) vector, making the CRISPR/Cas13d system more efficient for virus elimination and resistance prevention, taking into account that AAV has serotypes highly specific to the lung, the main organ infected by SARS-CoV-2 [180]
In a recent retrospective study, one dose (200 mL) of convalescent plasma (CP) collected from 10 severe adult cases has been reported to be tolerated; increasing or maintaining high level of neutralizing antibodies broke down the viral load in seven days, improve clinical symptoms and paraclinical criteria within three days and lung lesions were found to be differently absorbed on radiological examination within seven days [192]
Summary
Coronaviruses (CoVs) are a group of highly enveloped viruses that are diversely found in humans and wildlife With their high mutation rate and infectivity, CoVs are important zoonotic pathogens that can infect animals [1,2] and humans, leading to 5–10% of acute respiratory syndromes [3]. Comparative genome dogs forofSARS-CoV and camels in the case of MERS-CoV, acquiring the ability to infect studies published in recent papers strongly support the hypothesis that. These species molecular studies, the ACE2 proteins of non-human primates, pigs, cats and ferrets closely resemble These species may be susceptible to SARS-CoV-2 4infection, as has been shown for SARS-CoV. Based on the genetic sequence identity and the phylogenetic reports, SARS-CoV-2 is sufficiently different from SARS-CoV; WHO has classified it as a new Betacoronavirus that infects humans [30].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
