Big gaps in vaccine rates across the US worry health experts

James Martin discusses his hesitancy to get a COVID-19 vaccine while stopping at a store in Clanton, Ala., on Wednesday, May 19, 2021. Martin said he doesn’t trust the vaccines because of the speed with which they were developed and a lack of knowledge about long-term effects. (AP Photo/Jay Reeves)

People work at a mass vaccination site operated by the University of Alabama at Birmingham on Tuesday, May 18, 2021, in Hoover, Ala. Across the Deep South, where vaccination rates are the lowest in the nation and mistrust remains high, this site, one of the largest clinics in Alabama already shut down Wednesday and others will follow in the coming weeks because demand for the shot has plunged. (AP Photo/Jay Reeves)

Kevin Fisher, of Quincy, Mass., left, receives his second shot of Moderna COVID-19 vaccine from RN Katherine Francisco, of Avon, Mass., right, at a mass vaccination clinic, Wednesday, May 19, 2021, at Gillette Stadium, in Foxborough, Mass. A month after every adult in the U.S. became eligible for the vaccine, a distinct geographic pattern has emerged: The highest vaccination rates are concentrated in the Northeast, while the lowest ones are mostly in the South. (AP Photo/Steven Senne)

FOXBOROUGH, Mass. — A steady crowd of people flowed into the New England Patriots’ stadium for their second dose of the COVID-19 vaccine this week in Massachusetts, which is nearing its goal of vaccinating more than 4 million and plans to close its biggest clinics in little more than a month.