This is Science Friday. I'm Ira Flato. Later in the hour, a look at solar power and why it's the biggest disruptor of fossil fuel energy.

But first, it's been a big week for news on the COVID front. With the Pfizer vaccine finally receiving full FDA approval, Moderna is in the process.

And in the wake of that, many organizations are moving toward mandatory vaccinations.

It remains to be seeing just how much that will move the needle on vaccination numbers and cases and hospitalizations in the US.

And big questions remain about the future of the pandemic as well.

Joining me now to talk about some of them is Sarah Zang, staff writer for the Atlantic. Welcome back, Sarah.

Hi, thanks for having me.

Nice to have you as always. Maybe the biggest practical COVID news this week is that final approval of the Pfizer vaccine?

Yeah, absolutely. I think this is going to be a really important step to getting more people vaccinated.

Is it going to convince everyone to get vaccinated? Definitely not. You know, we seem like vaccine hesitancy is like a really heterogeneous thing.

People have different reasons. Maybe some people be convinced. But as you said earlier, I think the really big deal is that this is going to power a lot more employers, a lot more school, some mandate vaccines.

You know, we're already seeing that the military is not going to be mandating the COVID vaccine. Disney World Employees, you know, people who work for New York City, bunch of universities with the Pfizer vaccine getting improved.

They're now making everyone who can get the vaccine, get the vaccine.

And increasing vaccination numbers shifts that already complicated risk equation, right? I mean, on the one hand, you have more people getting vaccinated. But on the other hand, you have this delta variant.

Yeah, I feel like it's been really confusing the past several months because you know, over the previous year, we kind of decided what kind of risks were okay with an immodal pandemic. And then we have these two big things that have changed right we have vaccines and we have the delta variant.

We put them together. It's even more confusing thing because what's going on is that we're seeing the vaccines are slightly less effective against delta. We are seeing more breakthrough infections.

We are seeing that people who get breakthrough infections can transmit the virus. But we don't really have a good sense of exactly how much that is happening. The US hasn't really been collecting the data.

The CDC decided they weren't going to collect data on mild breakthrough infection. So we're kind of flying a little bit blind here relying a lot on what's going on in other countries, try to give the sense of how much delta is affecting vaccine efficacy.

I think it's also so confusing about this moment is that we all sort of have different levels of risk right now, right? Like if you're vaccinated versus you're unvaccinated, your risk of COVID is just very, very different. And we have lots of mixed vaccination households. If you have kids in door 12, you know, a lot of times the parents are vaccine, but the kids can't be and this is just a such a confusing situation.

Yeah, and of course, schools are reopening everywhere and people are wondering, what do I do there? Populations that largely can't be vaccinated little kids.

Yeah, exactly. You know, when you kind of put all the pieces together, right, we're having more kids back in school in person this year. We have a more transmissible variant. And we have a lot of places, a lot of states where you're not allowed to wear a mask. It seems pretty likely we're going to be having a lot of transmission in schools. Now, you know, experts I've talked to you have said that if your school is doing all the things that I should be doing, you know, good ventilation, asking for kids, even regular testing, if that's available, vaccine, all the teachers.

And so, you know, I think that's the case, and I think the problem is that a lot of places are not doing those things and especially not doing masks, not doing testing. It's a really tough time for parents, you know, we're already seeing that lots of schools are sending thousands of kids to quarantine and isolation. Some schools have even started to go back to remote learning because there's just so many cases going on. I think the bottom line is even though the risk of COVID to most kids is pretty low.

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