Research, Development and Application of COVID-19 Vaccines: Progress, Challenges, and Prospects

The pandemic of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become the most formidable challenge to humanity in this century. The research and development of COVID-19 vaccines, which are believed to be the most effective tools to control this pandemic, has been a topic of critical importance, not only in the field of biomedicine but also in the entire international community. Here, we introduce the concepts related to COVID-19 vaccines, including their development process, clinical trials, designs and types. On this basis, we further summarize the research, development, and application of vaccines in different regions of the world, and describe the vaccines according to their respective regions. Finally, we discuss existing and emerging challenges, strategies and prospects of in the development and application of COVID-19 vaccines.