WATCH LIVE: Federal officials hold Operation Warp Speed briefing after 2nd COVID-19 vaccine ships

(This event is now over. Click here for the latest on the COVID-19 vaccine.)

Federal officials will hold a briefing on Operation Warp Speed Monday morning, a day after a second COVID-19 vaccine, this one from Moderna Inc., began shipping.

Senior officials with the U.S. Department of Health and Human Services and the Department of Defense will speak at 10:30 a.m. from Washington D.C.

The briefing will be livestreamed in this article but delays are possible. If there is not a livestream available, check back at a later time.

The vaccination program that began last week has already inoculated 556,000 Americans, according to the Centers for Disease Control and Prevention. The first vaccines are headed to the most vulnerable, including healthcare workers and nursing home residents.

The Advisory Committee on Immunization Practices recommended Sunday that people 75 and older and essential workers like firefighters, teachers and grocery store workers should be next in line for COVID-19 shots.

The COVID-19 vaccine developed by Pfizer Inc. and Germany’s BioNTech already is being distributed. Regulators last week gave approval to the one from Moderna Inc. that began shipping Sunday.

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