Almost nine in ten Americans who received the first dose of a two-dose Covid-19 vaccine completed the regimen, and most people who received two doses received it within the recommended time frame, federal health officials reported Monday.
Analyzes by researchers from the Centers for Disease Control and Prevention included data on tens of millions of Americans who received the Moderna or Pfizer-BioNTech vaccines between mid-December and mid-February.
However, the percentage of people who completed the arrangements varied widely across jurisdictions and across populations. Federal health officials urged local vaccines to take action to make sure everyone comes back. This includes planning a return date for the first shot, sending reminders and postponing missed or canceled appointments.
While the data were overall “reassuring”, CDC researchers had said that the first groups to receive the vaccine in the United States – health professionals and long-term care residents – had easy access to the second dose, as they likely did had been vaccinated at work or at home.
As vaccines become available to a wider group of people, the scientists warned that the percentage of full vaccination could decrease.
People are not considered fully vaccinated against the coronavirus until two weeks after receiving the second intake of the two-dose regimen (or two weeks after receiving the single-dose vaccine made by Johnson & Johnson).
CDC researchers studied around 40.5 million Americans who were vaccinated between December 14, 2020 and February 14, 2021.
In one analysis, they checked the records of 12.4 million people who received the first dose of a two-dose vaccine and had enough time to receive the second dose. 88 percent had completed the series, while 8.6 percent were within the allowable 42 day interval to receive the second dose. But 3.4 percent missed this window. (The recommended interval between doses is 21 days for the Pfizer BioNTech vaccine and 28 days for Moderna).
Americans most likely missed the second dose, which varies by location. Among those vaccine recipients who were known to have racial and ethnicity information, the lowest graduation rates were from Native American or Alaskan people.
A second analysis of 14.2 million people who completed the full regimen found that 95.6 percent received the second dose within the recommended time frame, although again the numbers varied by community.
The study’s authors urged providers and public health workers to encourage Americans to return for a second dose and to highlight the importance of a full vaccination. CDC officials also urged vaccines to understand what is holding people back from completing the series, and whether access or lack of trust in the vaccines is a factor.
