Question: Back to the chart you shared last week plotting each state’s total cases/pop by vaccination coverage, what does the distribution look like when you add political affiliation?  And why are there a few outlier states (like Rhode Island)?

Answer: I used data from this morning’s NY Times COVID Tracker and data on the 2020 Presidential election results to make this scatter plot (Figure). As you can see (and as you hypothesized), there is a strong association between how a state voted in the 2020 Presidential election and its location on this chart.  States that voted for Biden (those in blue) are more likely to have higher vaccination coverage and lower total cases per population as compared with states that voted for Trump.  When it comes to outlier states, Rhode Island, with relatively high vaccination coverage and high cases per capita is likely in this unique position because of at least two reasons: 1) it was hit hard with the second wave in December, experiencing the highest cases per capita in the country at that time, likely due in part to how dense Rhode Island’s population is; and 2) it tests a LOT and has for a long time, maintaining some of the highest testing rates per capita in the country. When it comes to other outlier states, like Hawaii and Vermont, I suspect that the extremely low total cases per population are likely due to other public health measures both states implemented, including before vaccinations were available.  Indeed, in 2020 Vermont was frequently lauded for keeping the virus at bay. Hawaii’s response has been similarly lauded, although the state has more recently had a difficult time addressing vaccine hesitancy.

Figure. States with higher vaccination coverage have lower cases/population