Feb. 19, 2021 –Could one dose of the COVID vaccines protect as well as two? What about delaying the second dose to get more people vaccinated more quickly? Those questions were raised by three new research briefs.

Two of these briefs, one that appeared in The Lancet and another letter in the New England Journal of Medicine, suggested that single dose of the Pfizer-BioNTech vaccine could be around 90% effective between two and four weeks after the first dose. Together with previous findings that a single Moderna vaccine dose provides 92.1% efficacy against SARS-CoV-2 infection, investigators said it’s time to defer the second dose so more people can get protected with the vaccines.

Q&A With Dr. John Whyte (Feb. 19, 2021)John Whyte, MD, MPH, Chief Medical Officer, WebMD, answers viewers' questions about COVID-19 vaccines.392


JOHN WHYTE: Welcome, everyone.

I'm Dr. John Whyte,

chief medical officer at WebMD.

And you're watching Coronavirus

in Context.

Today, I'm going to answer

your questions.

You've been e-mailing me.

You've been posting

on social media.

And I'm going to take the time

to answer what's on your mind.

So let's start off.

Our first question

is from Annette on Facebook who

writes, Dr. Whyte,

do we have to get the COVID-19

vaccine every year like the flu


Does it help protect

against the new strains


Well, Annette, we're still

figuring out for sure

whether we're going to need

vaccination every year.

What we think right now

is that it likely gives

protection immunity for at least

several months,

maybe even several years.

The strains, those mutations,

though, are causing us

some pause

because what we've seen

is we know the mRNA vaccines

from Pfizer and Moderna

do protect against all

the variants

although less protection

but still enough for the South

African variant, AstraZeneca not

as much protection for the South


So we're going to have to see.

It's likely that we may all need

a booster shot to protect

against those variants

especially if we don't pick up

the pace of vaccination.

Mutations don't happen

if the virus doesn't survive.

So the quicker we get everyone

vaccinated, the more likely

we're going to be protected

from those variants.

And if that happens, then we're

not going to need a shot

every year or booster.

So we'll still have to wait

and see.

I don't know the answer

for sure.

I'm hoping that we don't.

But we're going to need to watch

those variants.

All right, our second question

is from Garden also

from Facebook.

And she says, what about those

with autoimmune diseases?

Anything like a vaccine greatly

stirs up my antibodies

and wreaks havoc on my body.

I'm fearful of both COVID

and the vaccine.

Garden, what we do know

is that those people

with autoimmune diseases

often are at greater risk

if they catch COVID of having

a bad outcome.

That's the real concern.

And remember, it's not just

about death.

It's also about long haulers

having complications from COVID

for many months and possibly

even years.

So that's why the CDC basically

recommends vaccination

for everyone other

than those who have had


a severe allergic reaction,

to some component

of the vaccine.

And that includes people

with autoimmune diseases.

And what you're talking about is

in many ways

your body overreacts, something

called cytokine storm.

And it attacks the good cells as

well as the bad cells.

The good news

is that these vaccines really

are an aspect of precision


They're very precise in terms

of developing antibodies

to the spike protein.

So we haven't seen any evidence

in tens of millions

of doses in the United States

of anyone

developing this over-response

in terms of immunity.

So you always still want

to check with your doctor.

But the recommendation

is that you go ahead and get


Our third question

is from Caroline.

And she writes, Dr. Whyte,

do we know if there's going

to be long-term effects

from the coronavirus shot?

Caroline, we have

excellent safety data.

In terms of vaccines,

where we see problems,

it's usually

in the first few days,

at the most the first two weeks.

We don't see complications

months later, years later.

And we have lots of good safety


So I'm not at all concerned

about any long-term

complications because we would

have already seen problems


And the number

of serious adverse events

is very, very low.

So it's always a risk

versus benefit.

Your risk of having

a serious side effect

from the vaccine is much less

than your risk of getting COVID

and having a bad outcome.

Our next question is from Joe.

And Joe writes, I was

on an antibiotic

when I got my first shot.

Does that make it any less


Joe, being on an antibiotic

doesn't make the vaccine less


We have started to see some data

about the use


nonsteroidal anti-inflammatory

diseases and steroids

because those could decrease

your immune response.

And some people have even

suggested-- because we know

people are getting some side

effects, some arm soreness,

headache-- maybe you should take

NSAIDs, Motrin, ibuprofen

before you get the vaccine

so you weaken any type of side

effects you have.

You might also be weakening

the immune response.

So I'm not worried

about antibiotics or anything.

But I would say maybe hold off

on nonsteroidal

anti-inflammatories and steroids

when you get the vaccine.

And finally, our last question

is from Twitter.

And Uche asked, does the vaccine

cure COVID-19?

Remember, vaccines are

to prevent disease.

It's not for treatment.

And if you actually have COVID,

we recommend that you wait

typically around 90 days

before you get vaccination.

It's the way to prevent it,

not to treat it or not to cure.

Those are the questions we have

this week.

I want to thank you all

for sending them in.

Remember, you can email me

at [email protected]

and post it

on our social properties

Thanks for watching.


John Whyte, MD, MPH, Chief Medical Officer, WebMD./delivery/aws/db/a0/dba06f67-edc4-3b7e-8084-49d62df1fb8a/JW_Summary_QA_021021_v6_,4500k,2500k,1000k,750k,400k,.mp402/19/2021 15:39:0018001200JW_Summary_QA_021021_1800x1200/webmd/consumer_assets/site_images/article_thumbnails/video/covid19-images/JW_Summary_QA_021021_1800x1200.jpg091e9c5e82119731

Anthony Fauci, MD, who directs the National Institute of Allergy and Infectious Diseases, weighed in on these findings on Friday, saying the U.S. will stick with a 2-dose strategy for now.

“And the reason is, even though you can get a fair degree of protection after a single dose, it clearly is not durable,” said Fauci at a briefing Friday from the White House COVID response team.

Andy Slavitt, White House senior advisor on the COVID-19 response, said they would need more research to make any changes to vaccine dosing.

“I think we've got the best people in the world looking at this. I feel very confident and they'll look aggressively at these studies, but I think it's important that you let people understand that we're not going to be persuaded by one study that happens to grab headlines,” said Slavitt.

In a letter published in the New England Journal of Medicine, researchers said a single dose of the Pfizer/BioNTech vaccine offers 92.6% efficacy based on the companies’ own data submitted to the FDA.

The second dose adds little short-term benefit, "while high-risk persons who could have received a first dose with that vaccine supply are left completely unprotected," wrote authors Danuta M. Skowronski, MD, of the British Columbia Centre for Disease Control in Vancouver, Canada, and Gaston De Serres, MD, PhD, of the Quebec National Institute of Health, Quebec City, Canada

In addition, correspondence in the Lancet February 18 appeared to further fortify the single dose Pfizer vaccine strategy. Researchers in Israel reported that one dose was associated with 85% protection against symptomatic COVID-19 in an adjusted analysis of more than 9,000 health care workers eligible for immunization.

"Deferral of the second dose of the COVID-19 vaccine will enable more individuals within our high-risk and health care worker priority groups to receive a single dose," Skowronski said. "Since a single dose provides swift and substantial protection exceeding 90%, and a second dose provides little added benefit in the short term, second dose deferral will maximize the benefits of scarce vaccine supply while the pandemic risk remains elevated."

But Fauci said that protection, while good, doesn’t last long.

He pointed out that a second dose boosts by 10-fold the number of neutralizing antibodies made in response to the vaccine.

He said this large increase in antibodies becomes important from the standpoint of circulating virus variants. People who get a booster have a cushion that may help prevent severe disease, even if they're infected by one of the variants that's evolved to escape some of the vaccine's protection.. More antibodies also means the virus has less chance of escaping and creating new variants.

Other experts agreed, saying more data are needed before changing the two-dose regimen. They also point out that the FDA granted emergency use authorization based on the two-dose studies.

" The studies did not actually look at just giving one dose and trying to just go with that," Dial Hewlett Jr, MD, medical director of the Division of Disease Control at the Westchester County Department of Health in White Plains, NY, said today during a media briefing, sponsored by the Infectious Diseases Society of America.

"It may be true that in the short run, one dose might be effective," Hewlett said, "but we don't know how long that this protection will last, and is the second dose going to be adding to that?"

But Skowronski and De Serres wrote that "given the current vaccine shortage, postponement of the second dose is a matter of national security that, if ignored, will certainly result in thousands of COVID-19-related hospitalizations and deaths this winter in the United States — hospitalizations and deaths that would have been prevented with a first dose of vaccine."