(CNN/CBS13) – A US Centers for Disease Control and Prevention advisory panel on Sunday recommended that adults 75 and older and frontline essential workers – including police, grocery workers and teachers – be next in line to receive COVID-19 vaccines.

That would put those people in “Phase 1b” of allocating the vaccine nationwide.

The panel vote also included prioritizing adults ages 65 to 75, people ages 16 to 64 with high-risk medical conditions and “other essential workers” in “Phase 1c” of allocation.

“They really serve to address the current lack of vaccine supply and address those individuals with the highest risk for disease,” Dr. José Romero, chair of the Advisory Committee on Immunization Practices and secretary of the Arkansas Department of Health, said about the recommendations.

The Advisory Committee on Immunization Practices met on Sunday to discuss Phases 1b and 1c of vaccine distribution. In a previous meeting earlier this month, the group voted on Phase 1a, which advised giving the first round of vaccines to health care workers and residents of long-term care facilities.

The Moderna vaccine on Friday became the second COVID-19 vaccine to be authorized by federal officials for emergency use. California began receiving allotments of the Pfizer vaccine last week.

On Sunday, Gov. Gavin Newsom said the state is expecting to begin receiving 672,000 doses of the Moderna vaccine this week.

More from CBS Sacramento:

Who is an essential worker?

A workgroup within the advisory committee defined frontline essential workers as “workers who are in sectors essential to the functioning of society and are at substantially higher risk of exposure” to the virus.

The frontline essential workers in Phase 1b include first responders, people in the education sector, those who work in food and agriculture, those in manufacturing, corrections workers, US postal service workers, public transit workers and grocery store workers.

It is estimated that there are about 30 million frontline essential workers in the United States.

The category of other essential workers in Phase 1c includes people in transportation and logistics, food service, construction and shelter and housing, finance, IT and communication, the energy sector, the media, the legal sector, public safety and water and wastewater industries.

It is estimated that there are about 57 million other essential workers in the United States.