Via Teleconference 

11:02 A.M. EDT

MR. ZIENTS: Good morning, and thanks for joining us.

It’s been a week of important progress in our fight against the virus. We rolled out our operational plan to protect kids ages 5 through 11, pending FDA and CDC’s determination of Pfizer’s vaccine for this age group.

Globally, we delivered our 200 millionth dose to over 100 countries. Tens of millions Americans became eligible for enhanced protection from a vaccine booster shot.

And nationwide, cases and hospitalizations are down more than 50 percent since September.

So, a week of important progress and further evidence that President Biden’s plan to fight the virus is working.

Today, we will focus on our boosters program. First, I’ll turn to Drs. Walensky and Fauci to discuss the FDA and CDC decisions this week and the science behind vaccine boosters.

Over to you, Dr. Walensky.

DR. WALENSKY: Thank you, Jeff. Good morning. Let’s begin with an overview of the data. As of yesterday, the seven-day daily average of cases was about 73,000 cases per day, which represents a decrease of about 15 percent over the previous week. The seven-day average of hospital admissions was about 6,000 per day, also a decrease of about 10 percent from the previous week. And seven-day average daily deaths were about 1,250 per day, a decrease of about 4 percent from the previous week.

As Jeff stated, this week marks another important step in our vaccination program, and I want to walk you through the important updates.

Yesterday, CDC’s Advisory Committee on Immunization Practices, or ACIP, discussed the data for Moderna and Johnson & Johnson COVID-19 booster doses.

Following a robust discussion, the committee unanimously recommended expanding who may benefit from a booster dose. Following their deliberation, I endorsed their recommendations such that we now have booster recommendations for all three authorized COVID-19 vaccines.

I want to state clearly our current recommendations for COVID-19 booster doses. For those who received an mRNA vaccine, Pfizer or Moderna, there are several groups of people who are eligible for a booster shot six months or more after their primary series, including: those who are 65 and older; those who are 18 and older and live in long-term care settings, have underlying medical conditions, or live or work in high-risk settings.

For those who received a Johnson & Johnson vaccine, all people 18 or older who were vaccinated two or more months ago are eligible for a booster shot.

Now that there are recommendations for booster doses for all vaccine primary series, the next question is: With what?

Some people may have a preference for the vaccine type that they originally received because they did very well with their initial series. For all three vaccines, this is perfectly fine. And now, with 10 months of vaccine experience, some may have an expressed preference for one booster type over another.

FDA’s authorizations and CDC’s recommendations now allow for this type of mix and match. The recommendations made yesterday are yet another demonstration of our fundamental commitment to all of you to never lose sight of our collective goal to protect as many people as possible from COVID-19.

All three COVID-19 vaccines authorized in the United States are extraordinarily safe, as demonstrated by the over 410 million vaccine doses already given. And they are highly effective in reducing the risk of severe disease, hospitalization, and death, even in the midst of the widely circulating Delta variant.

Vaccination continues to be the best way to protect ourselves, our families, and our communities from COVID-19. Expanding vaccination coverage will not only reduce transmission of the virus, it will also help prevent new variants from emerging.

We will continue to do all we can to make sure that as many people as possible, both here in the United States and around the world, are vaccinated and protected from COVID-19.

As you have heard me say before, we will not boost our way out of this pandemic. And no vaccine, even a boosted vaccine, provides 100 percent protection. So even after you boost, it remains important for us to remain smart about our prevention strategies while we still have over 93 percent of our counties with high or moderate community transmission.

Currently, around 64 million Americans remain unvaccinated, leaving themselves and their children, their families, their loved ones, and communities vulnerable.

If you have not yet been vaccinated, I encourage you to take the time to get the information you need to make the decision to get vaccinated.

Thank you. I’ll now turn things over to Dr. Fauci.

DR. FAUCI: Thank you very much, Dr. Walensky. What I’d like to do over the next few minutes is underscore some of the science behind what you’ve just heard from Dr. Walensky.

If I could have the first slide.

We’ll talk about the “mix and match” boosting data, some follow-up recent data from Israel, and just some mention of the recently announced BioNTech-Pfizer phase three trial.

If I could have the next slide.

The fundamental scientific basis for the deliberations of the FDA, and ultimately the CDC, on boosters relate to a “mix and match” study that was conducted out of the NIH, and as shown in the preliminary data from this medRxiv paper that came out just about six or seven days ago. The bottom line of it all is that boosters work very well for increasing the titer of neutralizing antibodies.

In this study, which was a nine-grid study matching a particular vaccine product against three others in a boost, homologous boosts increased the titers anywhere from 4- to 20-fold, and heterologous boosts increased the titer anywhere from 6.2- to 76-fold. That’s antibody titer.

Now, let’s take a look at that in more detail.

Next slide.

This slide is a bit busy. But if you look at the very top of the slide, where it says “Ad26.COV2.3” [Ad26.COV2.S], that is the original primary regimen. The mRNA, which is the boost to that regimen, as you can see, brings the titer up 76-fold.

If you go down to the next level and look at what the J&J — the Ad26 — when it boosts itself, it brings it up 4.2-fold. And across the nine-point grid, you can see, as mentioned on the prior slide, both homologous and heterologous boosts work well from a laboratory standpoint.

Next slide.

Now let’s take a look at what the clinical effect of boosters are. Shown on the slide are data from Israel, namely, the absolute rate of confirmed infection per 100,000 risk-days. Striking in this slide is that if you look at the confirmed infections, in yellow, of people who have not been boosted across multiple age groups, you see a dramatic diminution in the infection, in green, for those who were boosts. This is for confirmed infection.

Next slide.

When you look at severe illness, you see very similar data. Twelve or more days after a third-shot boost of the BioNTech, there was almost a 19-fold lower incidence of severe disease in people older than 60 years old, and more than a 22-fold lower incidence of severe disease in younger people, from 40- to 60-year-old.

Next slide.

And then, finally, just pointing — bringing to your attention the announcement that was made yesterday from Pfizer-BioNTech about their randomized control trial of more than 10,000 people who received two doses of their vaccine and then got a 30-microgram booster. They had a relative vaccine efficacy of close to 96 percent compared to individuals who were not boosts. Of note, there were 5 cases in the booster group and 109 cases in the non-booster group — again, with a very favorable safety profile.

Back to you, Jeff.

MR. ZIENTS: Well, thank you, Doctors. Now, let me provide some more detail on our efforts to get booster shots in arms.

Based on the criteria Dr. Walensky just laid out, more than 120 million Americans will become eligible for a booster in the coming months. That’s two out of three fully vaccinated adults in the U.S. This includes over 60 million vaccinated with Moderna and J&J, on top of the 60 million vaccinated with Pfizer. Importantly, of that total of 120 million, about 70 million are eligible now, as of today.

Booster shots provide enhanced protection and are a significant step forward in our fight against the virus. And to be clear: We are ready to execute on boosters.

Over the last two months, we’ve prepared and our work is paying off. Ten million Americans have already gotten a booster shot. Over 40 percent of eligible seniors, those most at risk, have gotten their third shot. Hundreds of thousands of more people roll up their sleeves to get their booster shot each and every day. And we are ready to get booster shots in the arms of tens of millions of newly eligible Americans.

Thanks to the President’s aggressive actions, we have ample supply of all three vaccines: Pfizer, Moderna, and J&J. And we have a well-tested nationwide vaccine distribution and delivery system.

Boosters are free. No insurance or ID required. And getting a booster is easy and convenient. In fact, boosters are available at over 80,000 locations across the country, including more than 40,000 local pharmacies, as well as thousands of doctors’ offices, community health centers, rural health clinics, and community-based vaccination sites. 90 percent of Americans live within 5 miles of a vaccine site.

We’ve worked with governors, state and local health departments, pharmacies, community and rural health centers, and other partners to ensure vaccine sites and providers have operations in place to get shots in arms quickly, efficiently, and equitably.

Importantly, this includes connecting pharmacies and other vaccine providers with long-term care facilities so those most at risk can get their shots — their booster shots quickly and conveniently.

States are standing up more vaccination sites, launching robust public education campaigns, staffing up call centers, and deploying mobile clinics to help ensure people have easy access to boosters.

And thanks to the funding of the American Rescue Plan, states can receive 100 percent federal reimbursement for these and other booster operations and outreach activities.

Pharmacy partners are ready. Scheduling systems are being updated and staffing plans are in place to handle the increased volume.

Importantly, equity remains front and center. We’ve worked with states, pharmacies, and others to make sure they are making boosters available in the hardest-hit communities and helped community health centers and rural health clinics do the same.

Later today, we’ll meet with key partners, including governors, state and local health departments, and pharmacies, as they launch their Moderna and J&J booster programs.

We’re also getting resources to community groups, faith-based organizations, and local leaders so they can understand who’s eligible for boosters and spread the word in their communities.

The bottom line is that our booster program is off to a very strong start. And today, with additional boosters authorized, we’re accelerating with tens of millions more Americans now eligible for enhanced protection.

It’s been a very important week of progress in our fight against the virus, and we’re laser focused on executing against the President’s plan to move us further along on our path out of this pandemic.

With that, let’s open it up for questions.


MODERATOR: Thanks, Jeff. A reminder to please keep your questions to one question.

First, let’s go to Jeff Mason at Reuters.

Q  Thanks very much. Can you just spell out exactly what age groups are now eligible for the boosters and if you expect to expand that in the coming weeks? That just wasn’t entirely clear to me.

And, Dr. Fauci, if you might be able to explain “homologous” and “heterologous,” that would be — that’d be awesome, too.

MR. ZIENTS: Dr. Walensky, why don’t you take the first on who’s eligible, and, Dr. Fauci, the second.

DR. WALENSKY: Perfect. Okay. So, in terms of — for those who got J&J, everybody is eligible if you got your dose more than two months ago. So, anybody who got J&J, if their dose was more than two months ago, then they are eligible for a boost.

For those who got Pfizer and Moderna, if your dose was more than six months ago, you’re eligible if you’re over the age of 65, and you’re eligible if you live in a long-term care facility, and you’re eligible if you’re over the age of 18 and you have underlying medical conditions or you live or work in a high-risk place. So, all of those groups are currently eligible for a booster vaccine.

We are following the data in real time, and we are looking at its ongoing efficacy, as well as potential for waning, in our other age groups. And we will update our recommendations as soon as we have more data for recommendations for other age groups for the Moderna and Pfizer.

Dr. Fauci.

DR. FAUCI: Hey, Jeff. I’m sorry that — if I wasn’t clear on that. “Homologous” means you boost with the same product that was the original regimen. So, if I got mRNA from Pfizer, and I get boosted with Pfizer, that’s a homologous boost.

If I get originally vaccinated with J&J, and I get boosted with Moderna, that’s called a “heterologous boost.”


MR. ZIENTS: Next question, please.

MODERATOR: Let’s go to Jeannie Baumann at Bloomberg.

Q  Thank you so much for taking my question. I was wondering when we might have data on boosting with the 50-microgram dose of Moderna, since the NIAID study looked at a 100-microgram dose.

And then I was also wondering — it seems like the recommendations on boosting right now don’t necessarily make a preference on the series. And, you know, if more data become available, might there be a recommendation to do J&J followed by an mRNA if that, you know, ends up (inaudible)?

MR. ZIENTS: So, Dr. Fauci, on the 50-microgram dose — to you, first. And then, Dr. Walensky, on the second part of the question.

DR. FAUCI: Yeah, right now, the data that we got was the 100-microgram dose. The company itself is submitting data on the study that they did on 50. I’m not sure exactly when that’s going to be able to go to the FDA for regulatory approval. Maybe Rochelle knows better, but I’m not quite sure when that’s going to happen, Rochelle.

DR. WALENSKY: Yeah, thank you for that question, Jeannie. So, let me be very clear that the FDA authorization for a boost with Moderna, whether you’re boosting Moderna or you’re boosting anything else, is for a 50-microgram dose.

So, all of our Moderna boosts are for 50-microgram dose, and we’re reaching out and doing a lot of training and teaching with our providers, our pharmacists to make sure that the booster dose for Moderna is known to be a 50-microgram dose. That’s a half dose from the primary series.

With regard to your question for preference, you know, we will not articulate a preference. My understanding is that most people will have done largely well with the initial vaccine that they got and may express a preference, very much, for the original vaccine series they got, having done very well.

There may be some people who might prefer another vaccine over the one that they received, and the current CDC recommendations now make that possible.

MR. ZIENTS: Next question.

MODERATOR: Let’s go to Sabrina Siddiqui at the Wall Street Journal.

Q  Hi. Thank you, as always, for doing the briefing. This is probably a question for Dr. Walensky, but can you just clarify the guidance for pregnant people? I do believe that’s one of the underlying conditions. So, are you recommending boosters for all women or all people who are pregnant?

And also, is that true for nursing women? Because I think there’s been some confusion over how you would define people who are recently pregnant and whether or not they should get a booster.

DR. WALENSKY: Yeah, thank you, Sabrina, for that question. First and foremost, I want to really emphasize how important it is to get a primary series if you’re pregnant.

We have relatively low rates of vaccination for pregnant women in general. So, really important to consider pregnancy an underlying medical condition — high risk of COVID. And, yes, you are absolutely — you should get vaccinated if you’re pregnant.

If you are eligible for a boost and you’re pregnant, you should also get your boost during that period of time. And I would say for nursing as well.

MR. ZIENTS: Next question.

MODERATOR: (Inaudible) Pettypiece at NBC News.

Q  Hi. I have a mask question. I know most places still have high to moderate transmission right now. But as more communities start to get — I mean high to substantial community transmission — but as more communities start to get down into that low to moderate community transmission, is it still the recommendation that people who are fully vaccinated can go without wearing masks indoors if there is low community spread, or are you guys rethinking that at all?

MR. ZIENTS: Dr. Walensky?

DR. WALENSKY: Yeah, thank you for that question. You know, we still have 75,000 cases in this country. And I am very encouraged to watch these trends coming down.

But, as you know, we have still over 90 percent of our counties that are in substantial or high risk — high community transmission.

So, we’re watching that very carefully. We’re scaling up our vaccinations, scaling up our booster programs. And we will, you know, hopefully, have vaccinations for children as well. And as we watch the community levels come down, we will update our recommendations.

It’s important to note that, as we look at the current situation, we are also heading into respiratory virus season. During that season, we know respiratory viruses tend to thrive. And so, we’re taking all of those into consideration.

MR. ZIENTS: Okay. Kevin, last question.


Q  Thanks, as always, for doing this. Maybe for Dr. Fauci — I was hoping — is there any research regarding the booster doses’ ability to slow a person’s ability to transmit the virus, or any effect on transmission for vaccinated — between vaccinated and boosted individuals?

And then, maybe for Dr. Walensky and Jeff, is the administration rethinking the definition of what it means to be fully vaccinated now that these boosters are recommended? Should people who are eligible for a booster now get one by a certain timeframe to maintain their fully vaccinated status?

MR. ZIENTS: Dr. Fauci?

DR. FAUCI: Yeah, thanks for that question. There is highly suggestive data from the Israeli cohort, who is well into their boosting program, that in the boosting — which they’re essentially doing for everyone from 12 years old or older — they are finding that simultaneously with the clinical effect of decrease in infection and severe disease, they are seeing a gradual diminution coincident with the booster in what we call the “R nought,” or, namely, the transmissibility from one person to any of a number of other people. It has gone down from 1.33, to 1.11, to now 0.985.

So, although that’s not definitive, it does strongly suggest that there is an impact on transmissibility, but further studies would have to confirm that.

MR. ZIENTS: Dr. Walensky, on the definition of “fully vaccinated”?

DR. WALENSKY: Yeah, it’s a really great question.  Right now, we don’t have booster eligibility for all people currently. So, we are going to — we have not yet changed the definition of “fully vaccinated.”

We will continue to look at this. We may need to update our definition of “fully vaccinated” in the future. But, right now, what I would say is: If you’re eligible for a booster, go ahead and get your booster. And we will continue to follow.

MR. ZIENTS: And the current CDC definition, Dr. Walensky, is two doses of an mRNA vaccine and one dose of J&J, correct?

DR. WALENSKY: Absolutely, yes. Thank you.

MR. ZIENTS: Okay. Well, thank you everybody for joining. And I hope everybody has a good weekend. And we look forward to seeing you next week. Thank you.

DR. WALENSKY: Thank you.

11:24 A.M. EDT

To view the COVID Press Briefing slides, visit:

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