乌鸦传媒

More than one in 10 people in the U.S. have missed their second dose of the COVID-19 vaccine, new data from the CDC showed. As the country begins to see a rise in coronavirus cases caused by the highly transmissible Delta variant, public health experts are urging Americans to complete the vaccination process.

Around 88% of people who were eligible for a second dose received it as of June 16, according to CDC data shared with -- a decrease from the 92% completion rate seen earlier this year.

This adds up to nearly 15 million people who have not received their second shot -- which, for the Pfizer-BioNTech and Moderna vaccines is recommended 21 and 28 days, respectively, after the first dose. On top of that, 1.5% of people eligible for their second dose -- or 2 million people -- had not yet completed their vaccination series but were still within an "allowable interval" of 42 days between shots.

have found that the Delta variant does somewhat reduce the efficacy of vaccines, with one British study finding an overall 10% absolute reduction in vaccine effectiveness after both doses. Still, other studies have shown that getting the second dose can more than double the vaccine's efficacy; for example, a by Public Health England found that the efficacy of the Pfizer vaccine jumped from 33% with the first dose to 88% with the second dose.

"It's clear how important the second dose is to secure the strongest possible protection against COVID-19 and its variants -- and I urge everyone to book in their jab when offered," Matt Hancock, former U.K. health and social care secretary.

Adults under the age of 30 were the most likely to miss their second dose, according to CNN's report; adults ages 30-39 were the next age group found to be more likely than average to miss their second shot.

This fact didn't come as a surprise to Leana Wen, MD, MSc, professor of health policy at George Washington University's Milken School of Public Health.

"This is an age group of many people who are working, who probably have many responsibilities when it comes to childcare and other factors in their lives," Wen told 乌鸦传媒. "Getting a second dose of the vaccine may not be top of mind."

Like many other vaccines that require more than one dose, Wen said, there's always a drop-off to be expected between shots -- especially as COVID-19 stops being at the forefront of everyone's daily lives. But, in Wen's view, doctors might be able to play a crucial role in getting their patients fully vaccinated.

"If there's a patient who [doctors] are concerned will not return for that second dose, offer the Johnson & Johnson vaccine," Wen said. "One dose of the Johnson & Johnson vaccine is effective against COVID-19, including the Delta variant -- one dose of the mRNA vaccine is not."

According to the from the CDC, 55% of the U.S. population have received at least one dose of the COVID-19 vaccine, and 48% have been fully vaccinated. Among adults in the U.S., 67% of those over the age of 18 have received at least one dose, and 59% have been fully vaccinated.

Comment