In the timeline when many are already doubting the safety and workability of the COVID-19 vaccines being ambitiously used right now, will the vaccines be effective enough to fight out the new virus strains? Will it be safe for use in the future?

In the timeline when many are already doubting the safety and workability of the COVID-19 vaccines being ambitiously used right now, will the vaccines be effective enough to fight out the new virus strains? Will it be safe for use in the future?