A vial of Pfizer-BioNTech Covid-19 vaccine is seen at a pop up vaccine clinic in the Arleta neighborhood of Los Angeles, California, August 23, 2021.

A pharmacy in Virginia incorrectly administered Pfizer and BioNTech's Covid-19 shots to 112 children last week, according to the state Department of Health.

"The pharmacy attempted to provide a proper dose," Loudoun County Health Department director Dr. David Goodfriend told CNBC on Thursday. He said it appears the pharmacy did administer about a third of the adult dose, which should be the correct amount. However, "a lower dose is possible if not all of the 0.1 ml was administered into muscle," he said.