A scientific quest to find a vaccine had begun at the outset of the global pandemic. As it usually takes years to develop a vaccine – the polio vaccine took 7 years to develop and the chickenpox vaccine took 9 years – there is an expectation to have widespread availability of a vaccine within less than one year. The U.S. government has invested about $9.5 billion in the development of the vaccine and the EU has committed several billion dollars collectively. The Food and Drug Administration, which has the ultimate say on vaccine approval says a vaccine for COVID-19 will need to prevent disease or decrease symptoms in at least 50 percent of those who receive it.
Source: The Washington Post