www.ejpmr.com Kundan et al. European Journal of Pharmaceutical and Medical Research 718 ETIOLOGY AND PRECAUTIONS OF CORONA VIRUS Kundan J. Tiwari 1 *, Amol Deshmukh 2 , Kiran Suryavanshi 1 and Dr. Yogesh Ushir 3 1 Professor, SMBT Institute of Diploma Pharmacy, Nandihills Dhamangaon, Nashik 422403. 2 Professor, SMBT College of Pharmacy, Nandihills Dhamangaon, Nashik 422403. 3 Principal, SMBT Institute of Diploma Pharmacy, Nandihills Dhamangaon, Nashik 422403. Article Received on 18/02/2020 Article Revised on 08/03/2020 Article Accepted on 29/03/2020 INTRODUCTION Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is a novel virus that caused the first major pandemic of the new millennium. [1,2,3] The rapid economic growth in southern China has led to an increasing demand for animal proteins including those from exotic game food animals such as civets. Large numbers and varieties of these wild game mammals in overcrowded cages and the lack of biosecurity measures in wet markets allowed the jumping of this novel virus from animals to human. [4,5] Its capacity for human-to- human transmission, the lack of awareness in hospital infection control, and international air travel facilitated the rapid global dissemination of this agent. Over 8,000 people were affected, with a crude fatality rate of 10%. The acute and dramatic impact on health care systems, economies, and societies of affected countries within just a few months of early 2003 was unparalleled since the last plague. The small reemergence of SARS in late 2003 after the resumption of the wildlife market in southern China and the recent discovery of a very similar virus in horseshoe bats, bat SARS-CoV, suggested that SARS can return if conditions are fit for the introduction, mutation, amplification, and transmission of this dangerous virus. [6,7,8,9] Here, we review the biology of the virus in relation to the epidemiology, clinical presentation, pathogenesis, laboratory diagnosis, animal models or hosts, and options for treatment, immunization, and infection control. Viral Life Cycle Trimers of the S protein form the peplomers that radiate from the lipid envelope and give the virus a characteristic corona solids-like appearance under an electron microscope. S is a class I fusion protein that consists of the amino-terminal S1 and carboxyl-terminal S2 subunits connected by a fusion peptide. The two subunits are indispensable for receptor binding and membrane fusion, respectively. The receptor binding domain of S1 has been mapped to residues 318 to 510. [10,11] The binding of S1 to the cellular receptor will trigger conformational changes, which collocate the fusion peptide upstream of the two heptad repeats of S2 to the transmembrane domain, and, finally, fusion of the viral and cellular lipid envelopes. Moreover, this process could be facilitated by the infected cell membrane-associated protease, such as factor Xa, which can cleave S into S1 and S2. This proteolytic cleavage is specifically inhibited by a protease inhibitor, Ben-HCl. [12] The key receptor of the host cell attached by S is angiotensin- converting enzyme 2 (ACE2), which is a metalloprotease expressed in the cells of the lung, intestine, liver, heart, vascular endothelium, testis, and kidney. [13] Since ACE2 was shown to protect against acute lung injury in a mouse model and since the binding of the S protein to host cells results in the Down regulation of ACE2, this mechanism may contribute to the severity of lung damage in SARS. [14] Cells expressing some lectins, including DC-SIGN, L-SIGN, and LSECtin, have been shown to augment the cellular entry of pseudo type virus expressing S but only in the concomitant presence of ACE2. [15,16,17,18] Nonsusceptible cells expressing these lectins in the absence of ACE2, such as dendritic cells, were able to promote the cell- mediated transfer of SARS-CoV to susceptible cells. [15] Although lysosomotropic agents can block viral entry, which indicates that endosomal acidification is required for entry, the activation of the S protein by protease can SJIF Impact Factor 6.222 Review Article ISSN 2394-3211 EJPMR EUROPEAN JOURNAL OF PHARMACEUTICAL AND MEDICAL RESEARCH www.ejpmr.com ejpmr, 2020,7(4), 718-724 ABSTRACT The Coronaviruses (CoV) belong to the genus Coronavirus with its high mutation rate in the Coronaviridae. The objective of this manuscript is to have a preliminary opinion about the disease and prevention in this early stage of COVID-19 outbreak. KEYWORDS: COVID-19, Coronaviruses, outbreak. *Corresponding Author: Prof. Kundan J. Tiwari Professor, SMBT Institute of Diploma Pharmacy, Nandihills Dhamangaon, Nashik 422403.