COVID -19: EFFICACY AND SAFETY PROFILE OF MAIN VACCINES APPROVED FOR EMERGENCY USE AUTHORIZATION IN 2021

Coronavirus -2 (SARS-CoV-2), is a new member of the human coronaviruses family. It is a single-strand positive-strand nucleic acid (ssRNA), It also has spike (S), membrane (M), envelope (E), and nucleocapsid (N) proteins. The (S) protein is responsible for recognising and binding to receptors on the surface of host cells and plays an important role in the first step of viral infection. Coronavirus-2 is identified in late 2019 as the causative agent of a new disease (COVID-19) outbreak in China associated with severe medical complications and even death in some cases. In March 2020, the World Health Organization (WHO) announced the novel disease outbreak as a pandemic. Current Coronavirus pandemic is the most challenging health emergency to humanity in this century, with globally reported (184 .324 .026) confirmed cases and ( 3. 992. 680) confirmed deaths ,as of 7th July 2021, according to WHO.