Question

Compare and contrast the three types of coronaviruses: "SARS-Cov, MERS-Cov and Covid-2019" in regards to their replication cycle, transmission, R0

Answer 1

SARS-CoV-2 is the seventh member of the family of CoVs that infect humans. Four human CoVs (HCoV-229E, HCoV-NL63, HCoV-OC43 and HCoV-HKU1) are able to cause a wide range of upper respiratory tract infections (common cold), whereas SARS-CoV and MERS-CoV are responsible for atypical pneumonia. The causes of different infection sites are likely related to the presence of dipeptidyl peptidase 4 (DPP4) and angiotensin-converting enzyme 2 (ACE2) in the lower respiratory tract, which are the major human receptors for the surface spike (S) glycoprotein of MERS-CoV and SARS-CoV, respectively.The genetic sequence of SARS-CoV-2 is ≥70% similar to that SARS-CoV, and SARS-CoV-2 is capable of using the same cell entry receptor (ACE2) as SARS-CoV to infect humans,The novel CoV can be transmitted between humans via respiratory droplets. Notably, the respiratory tract is probably not the only route of transmission. Close contact is also a source of transmission of SARS-CoV-2. For example, SARS-CoV-2 can be transmitted through direct or indirect contact with mucous membranes in the eyes, mouth or nose,interferon-alpha (IFNα) IFNα is a member of the family of type I IFNs that plays an important role in host resistance to viral infection. IFNα suppresses viral infection by directly interfering with replication of the virus and by promoting both innate and adaptive immune responses. In vitro experiments showed that IFNα effectively inhibits the replication of SARS-CoV,It has also been reported that cynomolgus monkeys are protected from infection with SARS CoV by treatment with IFNα ,Moreover, the therapeutic benefit of synthetic recombinant IFNα for patients with SARS was demonstrated in a pilot clinical trial . Thus, IFNα should be considered a candidate drug for COVID-19 therapy