New Delhi: An effective vaccine is not likely to be available for the general public before the fall of 2021, according to experts working in the field of vaccine development.Researchers at McGill University in Canada carried out a survey of 28 experts working in vaccinology in late June 2020.The majority of those surveyed were mostly Canadian or American academics with an average of 25 years of experience working in the field."Experts in our survey offered forecasts on vaccine development that were generally less optimistic than the timeline of early 2021 offered by US public officials," Jonathan Kimmelman, a professor at McGill University, said in a statement."In general they seem to believe that a publicly available vaccine next summer.