Sarah Zhang writes:

Last winter, when vaccines were still incredibly scarce in the United States, Ashish Jha told The Atlantic that he was feeling optimistic about summer: By July 4, Jha, the dean of the Brown University School of Public Health, expected enough people to be vaccinated that he could host a backyard barbecue. Indeed, Jha confirmed to me this week, he will be grilling burgers and hot dogs for friends this Fourth of July. He had predicted back in the winter that guests would still need to mask up indoors, but even that feels unnecessary now. “Fifteen, 20 vaccinated people inside my house, if it starts raining, feels very safe,” he said.

This is because, he added, he lives in Massachusetts, which has one of the lowest COVID-19 case rates in the nation (fewer than one new case per 100,000 people a day) and one of the highest vaccination rates (82 percent of adults have had at least one dose). His town, Newton, is an outlier even among outliers: More than 95 percent of people older than 30 have gotten at least one dose. It’s one of the safest places in the world with respect to the coronavirus.

The outlook is dramatically different elsewhere in the country. COVID-19 cases are rising sharply in several states with low vaccine coverage, fueled by the spread of the coronavirus’s more transmissible Delta variant. In southwest Missouri, understaffed hospitals are already having to send COVID-19 patients hundreds of miles away. The same July 4 party that is very safe in Massachusetts is riskier in Missouri, where much more virus is circulating (15 new cases per 100,000 people a day) and many fewer adults are at least partially vaccinated (56 percent). [Continue reading…]