SACHA PFEIFFER, HOST:

Retail pharmacies have been a crucial part of the country's rollout of COVID-19 vaccines. But new reporting from Kaiser Health News finds that the majority of wasted vaccines in the U.S. comes from two big pharmacy chains, CVS and Walgreens. The findings are based on CDC data and show that those two companies are responsible for more wasted vaccines than federal, state and local government agencies combined.

Here to talk about this is reporter Joshua Eaton. He co-wrote the story with Rachana Pradhan for Kaiser Health News. Joshua, welcome.

JOSHUA EATON: Thank you for having me.

PFEIFFER: Would you help us understand the scope of this problem in terms of how many COVID-19 vaccine doses were wasted and over what period of time?

EATON: So the data we got from the CDC showed almost 200,000 vaccine doses wasted through March 29. And then we were able to get some more data from states that didn't report to the CDC. And that showed, combined with the CDC data, just over 200,000 doses wasted.

PFEIFFER: So roughly 200,000 doses wasted, and it sounds like at least 150 million doses out there, even if not administered. The waste is tiny, but waste is still waste. And there were many people who tried desperately and unsuccessfully to get vaccinated earlier this year. So in your reporting, how problematic did people tell you this waste was? Or did they just say it was inevitable waste and not that problematic?

EATON: We really have a limited view on this. We were able to get some data from Texas, but the CDC data didn't include Texas. So there's one problem, which is the waste, and then there's another problem, which is how limited our view is of what's been wasted and what's being used and what's not being used and where.

PFEIFFER: Joshua, your article talked about waste being the result of everything from broken syringes to vaccines that weren't kept cold enough and so essentially went bad. What else do we know about why waste would have happened?

EATON: Incidents where there were hundreds or sometimes even more than a thousand doses wasted at one time, it was almost exclusively either a freezer malfunction, or a worker left them out for too long at room temperature, and so they spoiled. So it was usually - it had to do with the storage requirements.

PFEIFFER: What have CVS and Walgreens said about these findings?

EATON: So CVS told us that despite the challenges, they worked very hard to eliminate waste. And they had approximately - they said one dose per onsite vaccination clinic that was wasted. And Walgreens said its wastage amounted to less than half a percent of vaccines they administered through March 29.

PFEIFFER: As more people get vaccinated, demand for vaccines will slow down. In fact, it - that's happening already in some parts of the country. Is there an expectation that this might contribute to more waste as clinics are held and people don't show up? And if so, is there any way to get ahead of that?

EATON: Experts told us that as we enter the next phase of vaccination, we're going to have to tolerate more vaccine waste. And that isn't necessarily a bad thing. If there are three people who come into a doctor's office on a given day and they want to get vaccinated, and the doctor's office has a vial with six doses in it, they may have to waste three doses. But it's worth it to vaccinate those three people. The other thing is, you know, with this limited view, it's difficult to know if there are places where there are problems with storage, if there are problems with procedures. So when you have this limited view of the data, it makes it harder to correct those kinds of problems.

PFEIFFER: That's Joshua Eaton, who reported on vaccine waste for Kaiser Health News. Thank you.

EATON: Thank you for having me.

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