Prior to COVID-19, the shortest amount of time it took to develop a vaccine was for mumps and it took roughly four years. The development and testing processes for vaccines normally take many years.
The rush for a COVID-19 vaccine is unprecedented in its speed. However, given the high rate at which possible vaccines drop off during the testing process, and potential manufacturing constraints, it will be difficult to produce, test, and scale a COVID-19 vaccine before 2021.
Because unparalleled efforts and funding are going into COVID-19 vaccine development, experts are hopeful to have a vaccine available much quicker.
Even after a COVID-19 vaccine is developed, adequate manufacturing, supply chain, and distribution networks also need to be coordinated in order to get the vaccine to people across the world.