关键词: 第二株SARS-冠状病毒, 2019冠状病毒疾病, 复制, 致死率, 发病率

Abstract: Coronavirus has been regarded as safe pathogen that causes no diseases or only induces milder syndromes. However, At the first 20 years as human society enters into the 21st century, the world has experienced three coronaviral epidemics(SARS-CoV in 2002—2003, MERS-CoV in 2012 and SARS-CoV-2 in 2019—2020) with the most severe in the latest one. By March 12, 2020, this outbreak has caused more than 126 000 confirmed cases with over 4 600 deaths. Similar with the previous two outbreaks, SARS-CoV-2 infection was also caused by cross species transmission that was believed to be derived from bats to human, although the intermediate hosts are still remained unknown. As the same as the previous two coronaviruses, SARS-CoV-2 also belongs to the pathogen that can infect lower respiratory tracts. Patients with underlying diseases such as diabetes and hypertension are more susceptible to this infection. The severe patients manifest not only different degrees of dyspnea, but also can sometimes develop functional damages in heart and/or kidney. The results of pathological autopsy indicated that the obstructive pulmonary ventilation failure in critical ill patients might be mainly due to the complete filling of excessive amount of viscous liquids in alveolar cavities and tracheas. Patients' conditions could be even worse when they develop the followings: lymphopenia, the increased level of CRP, cytokine storm caused by the large secretion of pro-inflammatory cytokines. Because of the quite differences in syndromes from patient to patient, diagnosis and treatment should be carefully evaluated and fully based on the illness as well as the patient’s condition so as to avoid improper treatments that might aggravate disease progression and even cause the deadweight loss in lives. This review attempts to summarize the current knowledge about the typical features of this novel coronavirus such as the structure of the viral genome, the origin of the virus, life cycle, morbidity, disease progression and the strategies of clinical prevention and treatments.

Key words: SARS-CoV-2, COVID-19, replication, mortality, morbidity