ATLANTA — Delta Air Lines said Monday it will continue to block some seats on all flights through spring break and Easter to provide a bit more space between passengers.

The Atlanta-based airline announced Monday it will limit capacity on flights through April 30. Delta said it will block middle seats in most cabins, although groups of three or more passengers can choose to sit together.

During the early days of the pandemic, several U.S. airlines blocked middle seats, although United Airlines never did. The others that temporarily limited the number of seats for sale have since dropped the practice, at least in the main cabin, including Southwest, JetBlue, Alaska and American.

A Delta official, Bill Lentsch, said the airline will monitor virus cases and vaccination rates as it reassess its seating policy.

Airlines that no longer block seats cite research by the Pentagon’s transport command and others that concluded the risk of transmitting the virus that causes COVID-19 during a flight is very low.

Air travel was a major vector of the disease, especially in the early part of the pandemic, before most countries imposed travel restrictions. Many health officials also blamed travel for surges in newly reported virus cases in the U.S. after Thanksgiving and Christmas.