Komal Bhombe, Int. J. Res. Pharm. Sci., 2020, 11 (SPL)(1), 1151-1155 REVIEW ARTICLE INTERNATIONAL JOURNAL OF RESEARCH IN PHARMACEUTICAL SCIENCES Published by JK Welfare & Pharmascope Foundation Journal Home Page: www.pharmascope.org/ijrps Coronaviruses outbreaks — Then to Now Komal Bhombe * , Vidya Baliga, Dhadse P V, Chitrika Subhadarsanee Department of Periodontics and Implantology, Sharad Pawar Dental College and Hospital, Sawangi (Meghe), Datta Meghe Institute of Medical Sciences (DU), Wardha, Maharashtra-442001, India Article History: Received on: 10 Aug 2020 Revised on: 10 Sep 2020 Accepted on: 15 Sep 2020 Keywords: Coronaviruses, COVID-19, MERS-CoV, SARS-Cov, SARS-CoV-2 ABSTRACT According to the World Health Organization (WHO), Viral diseases continue to evolve, posing a signiϑicant public health concern. Over two decades, several viral epidemics have been recorded wherein several strains of coronaviruses have been associated with epidemics causing severe respiratory complica- tions and even death. Recently, a novel strain of this virus has come into the picture, eventually leading the world towards a pandemic. The situation today is similar to that witnessed earlier named as “SARS-CoV” and “MERS- CoV” which also affected the respiratory system. Current evidence suggests that SARS-CoV-2 is propagating to humans via transmission from illegally sold wild animals in the Huanan Seafood Wholesale Market. Phylogenetically, it has been shown that SARS-CoV-2 is a new member of the Coronaviridae family and yet is distinct from SARS-CoV (79% identical) and MERS-CoV (50% iden- tical). Knowing the origin of such a pathogen is essential to develop the means to prevent further transmission and effective vaccines. This starts a discussion about the very origin of these viruses that have fanned a global emergency in the name of COVID-19. Therefore, the focus of this review is the origin, evolu- tion and emergence of CoV during “SARS-CoV”, “MERS-CoV” and “SARS-CoV-2” along with possibilities of future outbreaks. * Corresponding Author Name: Komal Bhombe Phone: +91-8805259554 Email: kbhombe@gmail.com ISSN: 0975-7538 DOI: https://doi.org/10.26452/ijrps.v11iSPL1.3571 Production and Hosted by Pharmascope.org © 2020 | All rights reserved. INTRODUCTION “Coronaviruses” (CoV) belong to the order “Nidovi- rales”, family “Coronaviridae” and subfamily- “Coro- navirinae”. (Payne, 2017) Based on their phyloge- netic relationships as well as genomic structures the subfamily consists of the following genera namely Alpha, Beta, Gamma and Delta coronavirus of which only α-and -coronaviruses are known to affect mam- mals (Figure 1)(Cui et al., 2019). More than 60 coronaviruses have been isolated from bats, most of which are- corona viruses. Bats are recog- nized as large and highly mobile repositories of CoV and are also linked with the coevolution of these viruses. (Payne, 2017) These viruses are known to cause respiratory as well as gastrointestinal infec- tions. The widespread of Covid-19 is not the ϑirst in history. Similar events have occurred over the past decades, with evidence pointing to a crossover of animal -coronaviruses to humans leading to severe diseases, including the ongoing and evolving pan- demic. During the outbreak of “Severe Acute Respiratory Syndrome” (SARS-CoV), a new coronavirus of - genera was identiϑied in the Guangdong region of southern China in 2002-2003. The origin of the spread was traced back to bats and was transmit- ted to other animals (civet cats and raccoon dogs) which acted as intermediary hosts. An animal-to- human transmission was then reported. Accord- ing to WHO reports, the epidemic had a mortal- ity rate of 11%, affecting around 26 countries with © International Journal of Research in Pharmaceutical Sciences 1151