The CDC reported 11.3 million wasted COVID-19 vaccine doses in 8 months

a data scientist
3 min readSep 5, 2021


By the end of July, the U.S. Center for Disease Control (CDC) had administered nearly 368 million doses of the COVID-19 vaccine. In the process, at least 11.3 million doses (~3%) were wasted.

Total number of wasted doses by week, which has been steadily growing since April.

The CDC data is missing entire states like Michigan and Connecticut, federal vaccination programs like the Department of Defense and U.S. Bureau of Prisons, and various smaller vaccination programs that do not report wastage to the CDC. As of August, at least 15 million doses have been wasted, with the full scale of wastage yet to be accounted for.

How vaccines get wasted

The mRNA vaccines developed by Pfizer, Moderna, and J&J must be kept at a specific low temperature during transport and storage, so any refrigeration problems can cause a mass wastage of doses. The Moderna and Pfizer vaccine must be administered within 6 hours of removal from temperature control, while the J&J vaccine must be used within 12 hours. Some vaccines come in vials of five doses each, while others come in vials of ten, leading to waste when a full vial cannot be used in time.

Wastage grouped by vaccine manufacturer. 56% of wasted doses were of the Moderna vaccine, 32% were Pfizer, and 12% were from J&J.

The CDC released guidelines on how vaccine providers should minimize waste, and the WHO recommends keeping waste below 1%.

Where vaccines get wasted

More than half of all waste occurs at Walgreens, CVS, Walmart, Rite Aid, and major retail pharmacies.

Waste by vaccine provider. Large retail pharmacies account for around two-thirds of all reported vaccine waste — state vaccination programs, hospitals, clinics, and smaller providers account for the remaining third.

When an instance of waste is reported to the CDC, the provider name includes the pharmacy store number (e.g. “WALGREENS #123” or “RITE AID 00120”). Store locators like the one for Walgreens make it easy to programmatically retrieve the latitude/longitude of a particular store, which can in turn be used to generate a relatively high-resolution heat map of vaccine waste in the United States over time. I’m working on mapping all retail pharmacy locations to waste over time — if you have data on pharmacy locations (ideally with latitude/longitude), I would greatly appreciate if you could email them to me.

I am currently exploring the data with the Wolfram Language, which is how I found that the “submitted” date is not exactly correlated with the actual day a dose was wasted.

FOIA request

Data on vaccine waste was not publicly disseminated anywhere, so I filed a FOIA request with the CDC for any relevant information.

I did not qualify for a fee waiver since my website seemingly wasn’t enough to demonstrate that I disseminate information to the public.

My request finally received a response containing a massive Microsoft Excel 2007 spreadsheet with a row for every reported instance of waste. You can avoid the horrendous CDC interface for FOIA requests, and the difficulty/cost of this process, by downloading the raw data I received from the CDC as well a nicely-formatted NDJSON file where I made a first attempt at parsing the values and cleaning things up.

You can also use the aws command line utility to download this dataset and all future updates.

aws s3 cp s3://adatascientist/cdc/ .

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I’ve had some months since my last post, and have some projects like this one in the works that will get my motivation back to where it used to be. Stay tuned!