Covid-19 vaccine may have unpleasant side effects. That will mean it’s working.
Early data suggest several of the coronavirus vaccines may cause people to feel crummy for a few days. And then they’ll need a second dose.
Pfizer is expected to seek federal permission to release its Covid-19 vaccine by the end of November, a move that holds promise for quelling the pandemic but also sets up a tight time frame to make sure consumers understand what it will mean to get the shots.
