COVID-19 Pandemic: The Origin, Transmission, Pathogenesis, and Therapeutic Application

An outbreak of atypical pneumonia reported in late December 2019, which subsequently progressed to global health crises of significant magnitude within the first three months after its appearance and the etiology was traced to a seafood wholesale market in the city of Wuhan, China. Where a large number of infected patients are presumed to have been exposed to the wet animal market and this was the first confirmed incident recorded. The genome sequence of this unknown pathogen was obtained and then through carefully genome sequence comparison with the already previously characterized corona viruses; SARS-CoV and MERS-CoV, it was found that a betacoronavirus belonging to subfamily orthocoronavirinie is responsible for the pneumonia cases. This suggested that Wuhan was the site where COVID-19 first started and the disease is zoonotic in origin. COVID-19 pandemic has presented considerable challenges to public health care systems at global scale and dictates almost every aspect of medical practice and policies across the world. Apparently, an effective treatment therapy against COVID-19 is the most urgently needed to curb the rapidly increasing incidence of SARS-CoV-2 infections. Unfortunately up to this moment there is no approved drug for the treatment of COVID-19 patients, although many reports are suggesting the drugs which were previously used against SARS-CoV and MERS-CoV such as remdesviri, lopinavir, ritonavir, interferon beta-1b, and ribavirin but these are being tested in randomized trials and again mostly showing less clinical benefits. Use of a triple combination of interferon beta-1b, lopinavir-ritonavir and ribavirin drugs were reported to be effective than when each drug is used separately, however, collaborative investigations are needed to ascertain the fidelity of these drugs. In this review, we summarize the latest research progress of the origin, pathogenesis, clinical characteristics of COVID-19, and discussed the current treatment regimens for combating the COVID-19 pandemic