Dr. Leana Wen explains how the CDC's Covid-19 safety guidelines have changed, given what scientists now know about how it spread.
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Many grandparents have one goal in mind this winter: Get vaccinated so they can see their children and grandchildren again. But is that safe if their younger family members have not yet been vaccinated?
The slow vaccine rollout confirms public health officials' warnings that they lacked support or money to quickly get vaccines into arms. See some charts tracking US vaccinations.