Where Cases Are Rising and Falling in the U.S.

Over the last four weeks, the rate of new cases have surged in four states in the northern U.S. In South Dakota, new cases per 100,000 residents rose from an average of 30 per day on Sept. 17 to 74 per day on Oct. 15, an increase of 44 new cases. The recent rise in cases in Pennsylvania pales by comparison, with an increase of 4 new cases per 100,000 since Sept. 17.