ABSTRACT
In the past one and half year elapsed since the identification of the SARS-CoV-2 virus and its genome, an extraordinary effort by the scientific community has led to the development of many vaccine projects. More than ten vaccine candidates throughout the world have been granted approval for emergency use. Existing data suggest that these vaccines have the potential to protect individuals and curb the spread of COVID-19 pandemic. However, long term side-effects and certain unresolved issues associated with vaccine use need to be assessed as the time passes. This study reviews the most recent data of 12 vaccines which have been approved for use and presents information on their doses, composition, mechanism of action, side effects, etc.