The second dose is supposed to be given three weeks after the first for the Pfizer-BioNTech vaccine and four weeks for the Moderna vaccine (with a few days’ buffer on each side). In that group, 88 per cent of people had their second shot on schedule.
Around 9 per cent of people who had their first shot between December 14 and February 14 had not yet received their second dose but were still within 42 days from their first dose, the report said.
The CDC said that when a delay is unavoidable, people can wait that long. Three percent of people were outside of the 42-day window and had missed the dose, it added.