The delta variant poses more risks to unvaccinated people than any previous mutation of the coronavirus, including the risk of being infected by those who are vaccinated.

The number of COVID-19 cases has risen more than threefold in the past month, from a seven-day average of 11,470 on June 20 to 37,673 on July 20, according to the Centers for Disease Control and Prevention. Hospitalizations have more than doubled during that same time period, rising from 1,868 to 3,521.