ST. LOUIS (AP) — Mask mandates in St. Louis and St. Louis County slowed the spread of the coronavirus this summer when compared to neighboring counties that didn't require face masks, a Saint Louis University study found.

The study compared infections in St. Louis and St. Louis County beginning in July, when leaders in those communities began requiring masks, to neighboring Franklin, St. Charles and Jefferson counties, the St. Louis Post-Dispatch reported Wednesday.

The study found average daily case growth was 44% less in St. Louis and St. Louis County compared to the neighboring counties thr...