Two coronavirus vaccines entered the final phase of testing this week. There are now five shots in the pipeline. Scientists expect to know by the end of the year if any of them are safe and effective. VOA's Steve Baragona has this update.
Two coronavirus vaccines entered the final phase of testing this week. There are now five shots in the pipeline. Scientists expect to know by the end of the year if any of them are safe and effective. VOA's Steve Baragona has this update.
