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Americans were still processing Joe Biden’s victory when more big news arrived: a breakthrough in the search for a COVID-19 vaccine, courtesy of the drugmaker Pfizer.

We caught up with Sarah Zhang, a staff writer who’s covered the search for vaccines extensively, to unpack why she’s feeling good about this development—and how a Biden administration might handle the pandemic differently.

The conversation that follows has been edited and condensed.

Caroline Mimbs Nyce: You were surprisingly optimistic about yesterday’s Pfizer news. What excited you?

Sarah Zhang: The fact that this vaccine might be over 90 percent effective was a lot better than most people expected. It was certainly a lot better than the minimum the FDA set, and a lot better than what many scientists I’ve talked with expected.

For this to happen with a new vaccine, using a new technology, was just a really pleasant surprise.

Caroline: Today, you warn that this vaccine may launch at a particularly tricky time: the transition between two administrations.

What makes that so challenging?

Sarah: If everything goes to plan, scientifically, Pfizer will try to get emergency use authorization later this month. So the vaccine will hopefully be rolling out to the first people who are getting it—probably health-care workers—at the end of this year or the beginning of next year.

In the best-case scenario, you might say that Donald Trump really wants people to think he helped make a great vaccine. And that the Biden administration also really wants people to get this vaccine. Maybe we’ll have some sort of bipartisan—almost accidentally bipartisan—movement encouraging people to get the vaccine.

But this whole interregnum feels really unpredictable. Trump still hasn’t conceded the election.

Caroline: Trump could still compromise the vaccine rollout, you write. How so?

Sarah: He’s just a really loud voice.

Look at the contrast in how the president and the president-elect reacted to the Pfizer vaccine news. Biden praised the scientists who were involved and then really quickly pivoted to This is going to take a long time, whereas Trump tweeted in all caps: “STOCK MARKET UP BIG, VACCINE COMING SOON.”

The standard best practice is you let scientists speak first and you don’t overpromise. That is always going to get drowned out by Trump tweeting.

Logistically, vaccine distribution is going to happen at the state and local levels, and local health departments have been preparing for several months now. The unpredictable piece feels like the politics.

Caroline: You told me earlier that it’s remarkable how unremarkable Biden’s statements have been. Can you explain what you mean?

Sarah: They just sound like how politicians talked four or five years ago. It’s very boring, in a good way.

I think a lot of scientists are breathing a huge sigh of relief that under a Biden administration, you probably won’t have the president actively and openly fighting with agencies on Twitter.

Caroline: If a vaccine is approved, what would getting vaccinated look like?

Sarah: It will probably be well into next year before the average American is able to get a vaccine. This is a new vaccine. It’s comparatively fast to manufacture, but it still takes time to do so safely.

The Pfizer vaccine is two doses. Two doses means twice as much vaccine to make and twice as many syringes. And there’s the added logistical challenge of making sure that someone remembers to come back three weeks after the first dose. It just adds a layer of complication.

Illustrations by Guillem Casasús / Renderings by Borja Alegre

One question, answered: What happens, process-wise, if Trump never concedes?

Barton Gellman, our staff writer who warned weeks ago about that possibility, responds:  

We’ll have to invent a substitute. Normally, concession is the way our elections end. That’s how we know the election is over, because there is no single national authority who calls it otherwise—at least until Congress meets in joint session on January 6 to count electoral votes.

Some of the substitutes we’re improvising now include Fox News joining the other networks in declaring Biden president-elect; foreign government leaders (not including Russia or China) sending Biden congratulations; recognition that it’s over from the U.S. Chamber of Commerce and from Republican leaders such as George W. Bush and Mitt Romney—senior figures, but outliers still in their party.

Eventually, we’ll have certified results from all 50 states and the District of Columbia. Meanwhile, the summary dismissal of nearly all of Trump’s lawsuits is also a kind of concession substitute. Some of Trump’s own language, including private musings about running again in 2024, can likewise be seen as tantamount to concession.

With all that said, I don’t think we’re over the worst of this contest yet.

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