Pfizer vaccine has shown more than 90% effectiveness against Coronavirus. Pfizer has picked four U.S. States – Rhode Island, Texas, New Mexico, and Tennessee for experimentation of the vaccine. These states were chosen because of their diversity in population, overall size, and immunisation infrastructure. However, it was made clear that these states will not receive the vaccine doses sooner than the others. The vaccine will go to the EUA after large-scale trials.