The Food and Drug Administration has authorized the Pfizer-BioNTech Covid-19 vaccine for children between the ages of 5 to 11. The lower-dose vaccine is now available for 28 million children in the United States.

An advisory committee voted 17-0 this week to recommend the vaccine for children, saying the benefits of the vaccine are greater than the risks.

When Pfizer approached the FDA, they said their vaccine is 91% effective at preventing illness in children. They also said it appears to fight off the highly transmissible delta variant.