There are over 100 different vaccines are under development and at least eight of them are already in human trials globally, according to the World Health Organization. 

Pfizer, an American biopharmaceutical company confirmed it has started to test an experimental vaccine to fight the COVID-19 in the U.S. on Tuesday.

CGTN spoke to Jessica Justman, ICAP's senior technical director at the Columbia University Medical Center. She didn't believe that is will possible to have a vaccine that's really ready to go by end of this year. 

She said, "As much as we want everybody to go quickly, we also want everybody to be careful and develop a vaccine that is both safe and truly effective. There's no point vaccinating people with something that will be harmful."

She also encourages everyone to wear masks. "So to think carefully before you take risks and expose yourself to others and to remember that the mask is about protecting other people, not about protecting yourself," She said.