It has been much noted in the news in recent days that confirmed cases of Covid-19 have been soaring in a number of states in the US, primarily in the south and southwest. But it is of interest to examine how widespread this is, and how it correlates with the politics of the different states. With the politicization by Trump of what should be a matter of public health, states (and their residents) are responding differently in their management of this public health crisis.

One way to look at this is to group the states according to who won there in 2016: Trump or Clinton. This divides the country roughly in half, between more liberal and more conservative areas. The chart above shows what then results for daily new confirmed cases (on a 7-day moving average).

The division is stark. The states won by Clinton (which included New York, New Jersey, the Northeast, Illinois, California, and Washington) were exposed early to Covid-19. These states are generally more highly urbanized and there is more international travel by both residents and visitors. This left them especially vulnerable as the virus that causes Covid-19 started to spread (first with little knowledge of how fast it was spreading, due to blunders in rolling out the necessary testing program in February and into much of March). But after peaking in April, these states brought down the daily number of new cases by over 60%, although with a partial and still limited reversal in the past week.

The pattern in the Trump states is quite different. Confirmed cases rose in the period leading up to April (in part as testing only became broadly available then), but then leveled off in these states through essentially all of April and May. Furthermore, the numbers leveled off at roughly 10,000 cases a day, or less than half the 21,000 cases per day seen in the Clinton states at their peak. The Trump states are often more rural, and there is less international travel (by both residents and visitors), so the lower numbers there were taken by some as indicating they were less vulnerable to this infectious disease.