The novel corona virus infection is frighteningly increasing worldwide. The first known infection from Covid were discovered in Wuhan, China. However, the original source of infection is still unclear. Covid-19 is caused by Severe Acute Respiratory Corona virus (SARS-COV-2). WHO declared COVID-19 as a global pandemic in March11, 2020. So far millions of millions of people have contracted to the virus worldwide and it has contributed to millions of death. An immense effort of scientific community has led to the development of more than 300 vaccine project . Many of which are under still undergoing clinical evaluation . Before the vaccine is approved for use, it is extensively tested through several clinical trials to ensure the vaccine is safe and demonstrate that it induce immune response. Few vaccine have passed those clinical trials and have been approved by WHO for emergency use.
