The divide in travel patterns, based on anonymous cellphone data from 15 million people, suggests that Americans in wide swaths of the West, Northeast and Midwest have complied with orders from state and local officials to stay home. Disease experts who reviewed the results say those reductions in travel — to less than a mile a day, on average, from about five miles — may be enough to sharply curb the spread of the coronavirus in those regions, at least for now.

“That’s huge,” said Aaron A. King, a University of Michigan professor who studies the ecology of infectious disease. “By any measure this is a massive change in behavior, and if we can make a similar reduction in the number of contacts we make, every indication is that we can defeat this epidemic.”…

A half-dozen of the most populous counties where residents were traveling widely last week are in Florida, where Gov. Ron DeSantis resisted calling for a statewide lockdown until Wednesday. People in Jacksonville, Tampa, Daytona Beach, Lakeland and surrounding areas continued to travel much more than people in other parts of the country, putting those areas at a higher risk for outbreaks in the coming weeks.