In the race between vaccination and variants, how will we know that vaccination is winning? Tracking vaccination coverage systematically and accurately is crucial to understanding how the rest of 2021 will go. But currently, this tracking remains patchy & inconsistent. A .

The CDC reports state-level vaccine coverage (by dose and age group). While this gives an illusion of tracking geographic variation, it obscures communities that are falling behind in vaccination. For more on the importance of fine-scale vacc data: https://bit.ly/3uqEDuw  (2/)

I do know that the CDC recently released a map of county-level vaccination data, but the map only provides qualitative information for 2-dose coverage and the data is not available for download. (3/)

We've been tracking county-level vaccination data from state health departments since mid-January. We only have county data for about ~30 states so far, but this is already revealing the patchwork of vaccine coverage that is developing. http://www.vaccinetracking.us/  (4/)

Of the ~30 states, only a handful provide data for download. The rest have required daily scraping from websites + dashboards, each with their own unique format ( @AlexesMerritt). There are differences in dose reporting, geographic formats, and frequency of updates. (5/)

Things get really fun when it comes to denominators. Measuring vaccine coverage requires not only an accurate measure of doses in arms but also of the underlying popn size. Some states report a different county popn size than the Census which can shift coverage significantly (6/)

Of the missing 20, some provide only qualitative or non-machine readable county-level data; others provide no county-level data at all. For these, we have no option but to rely on state-level estimates of vaccine coverage. (7/)

At the state-level, there tend to be discrepancies in what is reported by the state vs what is reported by the CDC (often higher). From what I understand, this stems from whether the state includes doses administered at federal vaccination sites, but this is not consistent. (8/)

Finally, there is no federal reporting of vaccination by race/ethnicity, even at the state level and 20% of states don't even report vaccination by race/ethnicity. We've also been tracking this at http://www.vaccinetracking.us/  and I'll do another thread about those data. (9/)

So much of this feels like a rerun of the dire data situation from 2020. We must demand granular vacc data b/c low local vaccination = high variant emergence. And we must demand better tracking of vacc disparities because eligibility doesn't mean equity. #DataSavesLives (10/10)