White House COVID-19 advisors discuss vaccine shortages, variants and when to get second shot

A senior advisor to the White House COVID-19 Response Team says the US is hitting its target of vaccinating at least a million Americans a day, with an additional 10 million doses now shipping out to states each week.

Yet, to vaccinate all Americans 16 and older, Andy Slavitt says, will require about 500 million doses.

"We're taking action to increase supply and increase capacity," Slavitt says.  "But, even so, it will be months before everyone who wants to receive a vaccine will get one."

Slavitt says the federal government will do a better job of updating state leaders on how much vaccine they can expect to receive each week, so they can pass along that information to their vaccine providers.

The Biden Administration plans to launch 100 community vaccination centers over the next month, supply vaccines directly to pharmacies, deploy mobile vaccine clinics into hard to reach areas, and partner with community health centers in hard hit communities, Slavitt says.

This comes as the US confirmed 309 cases Tuesday of a new British variant of the virus that is more contagious and, some experts believe, more deadly.  

The B.1.1.7. variant is one of 3 emerging coronavirus strains scientists are closely watching, concerned they may be able to eventually evade the COVID-19 vaccines.

RELATED: COVID-19 variant found in Brazil, South Africa could pose higher reinfection risk, study suggests

Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases and chief medical advisor to the president, says there are early indications the vaccines may be slightly less effective at protecting against the  South African variant of the virus.

"So, looking forward, what we plan to do, in collaborating with the companies is to develop what we would call alternatives, or boosts, that would use the same platform, but would incorporate a particular immunogen that would address these particular variants," Dr. Fauci says.

The currently approved COVID-19 vaccines in the US require two doses. 

With supply still uneven, some of those getting their first shot are concerned about receiving their second dose on time.

CDC Director Dr. Rochelle Walensky says her agency recommends people get their second dose as close to the recommended intervals as possible.

The Pfizer vaccine doses, she says, should be given 3 weeks apart, the Moderna doses a month apart.

"However, we also know that life can get in the way, and that some of those doses may be missed in the best time window," Dr. Walensky says.  "In those rare circumstances, the second dose may be given up to 6 weeks or 42 days after the first."

The vaccines are not interchangeable, she says.  

Still, Dr. Walensky says, in rare cases where people lose their paperwork or cannot remember which vaccine they had for their first shot, they can receive either of the mRNA vaccines for their second shot.

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