Currently, the world is facing the COVID-19 epidemic, a disease caused by SARS-CoV-2. Emerging body of molecular evidences suggested a similar path to SARS and MERS viruses. A viral particles cascade enters into the human body through eyes, nose, and mouth, few of these viral particles reaches to the lower respiratory tract through breathing and here their spike protein act like a key and lock into epithelial cells which are the air sacs in lungs. SARS-CoV-2 is undetectable for a longer period of time than many other flu and coronaviruses. Once they entered inside body, they overtake the cell’s machinery, replicate, multiply and infect the adjoining cells. All the viruses have a tell-tale signature on the surface known as antigens, identifying these antigens is what activate the immune system by producing the antibodies. Researchers have shown that a wide range of immune cells that react to SARS-CoV-2 and helps in recovery could be helpful in the development of potential vaccines.