Nearly 1 million American children ages 5 to 11 have been vaccinated against COVID-19 as of Wednesday after the vaccine became available to the age group last week.

There have been 900,000 children who have received the Pfizer vaccine with another 700,000 appointments scheduled within the coming days. The White House has been working with health clinics, healthcare professionals, pharmacies, and schools to vaccinate as many children as possible.

"It’s going to give millions of American parents peace of mind," President Joe Biden said at a virtual political fundraiser touting the vaccine for children.

About 20,000 vaccination sites are operational for elementary school children across the country.

First Lady Jill Biden and Surgeon General Dr. Vivek Murthy are expected to begin a nationwide effort to encourage children to get vaccinated this week. Murthy says parents should talk to their child’s pediatrician if they have any questions or concerns.

"We urge you to do all you can to help parents and families learn about the vaccine and get access to it," Health and Human Services Secretary Xavier Becerra and Education Secretary Miguel Cardona wrote in a letter addressed to school superintendents and elementary school principals.

Since the start of the pandemic, 2 million children ages 5 to 11 have tested positive for the virus.