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Coronaviruses are members of the subfamily named orthocoronavirinae containing four genera: alphacoronavirus, beta coronavirus, gamma coronavirus and delta coronavirus. Alpha and beta coronaviruses infect only mammals and cause respiratory illness in humans [1]. The first coronaviruses were discovered in the 1960s, while the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) was the first human coronavirus pathogen detected in 2002. Since then, seven human coronaviruses have been found [2]. Covid-19 belongs to the beta coronaviruses [3]. It is a single-stranded, nonsegmented positive polarity RNA genome virus. Its virion has four major structural proteins: nucleocapsid protein (N), transmembrane protein (M), an envelope protein (E), and spike protein (S), the last three forming the virus envelope [3]. The most abundant protein is M, being responsible for the virus shape. Proteins S and M are transmembrane proteins involved in virus assembly during replication. The N protein is associated with the virus RNA inside the envelope (CoV replication cycle)[4]. S proteins are responsible for the crown-like appearance of the virus and they also are the most immunogenic part because they will bind with angiotensin-converting enzyme 2 (ACE2) receptors to enter the host cell [4, 5]. COVID19 was detected for the first time in Wuhan (China) in December 2019, then started spreading rapidly across the world, being able to spread by human-to-human transmission. COVID19 was found to have> 95% homology with the bat coronavirus and> 70% similarity with the SARS-CoV [6]. The World Health Organization declared COVID19 to …