A Comprehensive Review on Covid-19

During the past two decades, multiple viral epidemics have emerged, including the epidemics of H1N1 influenza in 2009 and the Acute Respiratory Syndrome Coronavirus (SARS-CoV) in 2002 - 2003. Moreover, the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) was initially recognized in Saudi Arabia in 2012. Recently, cases of another lower respiratory tract infection (LRTI) were discovered in Wuhan, Hubei province, China, on December 31st 2019, and reported to the WHO country office in the country. Studies in the field have referred to the identification of first symptomatic people in early December 2019. Since experts in the field could not determine the causative agent of the disease, they mistakenly categorized the first reported cases as pneumonia of unknown etiology (PUE). Therefore, the Chinese Center for Disease Control and Prevention (China CDC), as well as local CDCs, arranged a full outbreak investigation plan, ascribing the etiology to a newly discovered virus of the coronavirus (CoV) family (i.e., the causative agent of COVID-19).