Emerging novel coronavirus (2019-nCoV)—current scenario, evolutionary perspective based on genome analysis and recent developments

Malik, Yashpal Singh; Sircar, Shubhankar; Bhat, Sudipta; Sharun, Khan; Dhama, Kuldeep; Dadar, Maryam; Tiwari, Ruchi; Chaicumpa, Wanpen

During the first week of December 2019, a few cases of pneumonia appeared in the city of Wuhan, Hubei province of China. The patients exhibited a history of visiting the local nearby Huanan seafood market which deals in the sale of different live animals, where zoonotic (animal-to-human) transmission suspected as the main route of disease origin (Hui et al. 2020 ). Firstly, the affected patients presented with pneumonia-like symptoms, followed by a severe acute respiratory infection. Some cases showed rapid development of acute respiratory distress syndrome (ARDS) followed by serious complications in the respiratory tract. On Jan 7 th , 2020, it was confirmed by the Chinese Center for Disease Control and Prevention (CDC) that a new coronavirus has emerged and was named 2019-nCoV. As on February 4 th 2020, China has confirmed 20471 cases with 425 deaths and 2788 severe cases of 2019-nCoV. In addition to China, 24 different countries from Europe, Northern America, Southeast Asia, Eastern Mediterranean, and Western Pacific Asia have reported the confirmed cases of this disease making the total tally of confirmed cases to 20630 worldwide ( Figure 2 ). Although the mortality rate due to 2019-nCoV is comparatively lesser than the earlier outbreaks of SARS and MERS-CoVs, as well as this virus presents relatively mild manifestations, the total number of cases are increasing speedily and are crossing the old census. There is a high risk of human-to-human transmission which has also been reported in family clusters and medical workers. The infected patients with nCoV exhibit high fever and dyspnea with chest radiographs showing acute invasive lesions in both lungs.