NEW YORK (AP) — Kids at summer camps can skip wearing masks outdoors, with some exceptions, federal health officials said Friday.

Children who aren’t fully vaccinated should still wear masks outside when they’re in crowds or in sustained close contact with others – and when they are inside, the Centers for Disease Control and Prevention said. Fully vaccinated kids need not wear masks indoors or outside, the agency said.

The guidance is the first in a wave of updates that will incorporate the agency’s recent decisions on masks and social distancing. Last week, the CDC said Americans don’t have to be as cautious about using masks and social distancing outdoors, and that fully vaccinated people generally don’t need to follow such measures indoors, either.

Previously, the CDC advised that just about all people at camps should wear masks with only a few exceptions, like while they are eating, drinking or swimming.

But that was before U.S. adults began getting vaccinations in December, and before the U.S. government authorized Pfizer vaccinations for kids as young as 12 to 15.

About 2.5 million of the roughly 17 million U.S. kids in that age group have gotten at least one dose of vaccine since it was authorized less than three weeks ago. A second dose is also required, three weeks after the first, and then it takes two more weeks before the vaccine fully takes effect.