Question
"We have a series of variations on the theme of 'big exponential growth and then quick leveling off,' which seems to describe just about every European country (*except maybe Romania, but I'm going to ignore that for now), and then you have one instance of just 'steady nearly linear growth,' describing the US. Why is the US such an extreme outlier here, not so much in raw numbers but in trend?" Dan Zigmond.
Below is the chart that Dan is referring to (it is part of the Covid-19 - Globally report):
US deaths by state
Looking in more details at the Covid-19 deaths for the top 9 US States by population (sum 9 states/total US population=168 Million/331 Million ~ 51% in just under 20% of the US States by number)
We see that the trajectories for these states fall into various categories:
- States such as New York (and also not shown here: New Jersey, Massachusetts, Connecticut, Vermont, Maine) had an exponential growth period and then successfully succeeded in flattening the curve.
- Illinois and Pennsylvania also flattened their curves though less dramatically than New York.
- Others such as Florida, Texas, and Georgia experienced a dramatic midterm (starting June) boost
- Ohio, California and North Carolina have had an almost linear increase in deaths, with a slight kink upwards in July for California and North Carolina
US States with highest Positivity
Another set of US states (ones with higher Positivity) can be seen below:
We see that after early July there is an almost linear increase in deaths/million population
US States that are beating Covid-19
The web page https://www.endcoronavirus.org/states has a list of US states that are beating the Covid-19 virus. For those states, the chart below shows the Covid-19 deaths/million population.
It is seen that all the states apart from Arizona (see the Log10(Y-axis)) graph to the right for Vermont and Maine) had an initial exponential growth followed by a flattening late March to mid April. Arizona has taken longer to flatten its curve.
One can understand a correlation between NY, NJ and CT since the states coordinated their efforts (see https://en.wikipedia.org/wiki/COVID-19_pandemic_in_New_York_(state)).
Other US states with similar curve flattening
| Flattened state | ID | Covid-19 confirmed | deaths | deaths/confirmed% | confirmed/MPop | deaths/MPop | confirmed/Pop-Density |
| Delaware | DE | 35145 | 1475 | 4.2 | 37153.755 | 1559.30541 | 72.41 |
| District of Columbia | DC | 14743 | 617 | 4.19 | 21931.547 | 917.843351 | 1.34 |
| Illinois | IL | 268238 | 8599 | 3.21 | 20858.328 | 668.662779 | 1158.03 |
| Maine | ME | 4941 | 138 | 2.79 | 3716.9156 | 103.811851 | 114.64 |
| Maryland | MD | 117888 | 3855 | 3.27 | 19627.061 | 641.81529 | 190.52 |
| Massachusetts | MA | 125699 | 9245 | 7.35 | 18500.323 | 1360.67498 | 144.3 |
| Michigan | MI | 125742 | 6943 | 5.52 | 12672.314 | 699.717493 | 716.48 |
| New Hampshire | NH | 7781 | 438 | 5.63 | 5847.7027 | 329.172829 | 52.35 |
| New Jersey | NJ | 197792 | 16054 | 8.12 | 22079.897 | 1792.1385 | 162.38 |
| New York | NY | 446366 | 33042 | 7.4 | 22548.531 | 1669.1427 | 1062.62 |
| Rhode Island | RI | 23358 | 1081 | 4.63 | 22113.078 | 1023.38545 | 22.86 |
| Vermont | VT | 1702 | 58 | 3.41 | 2718.6674 | 92.645541 | 25.06 |
| Connecticut | CT | 55166 | 4487 | 8.13 | 15362.782 | 1249.55234 | 74.39 |
| Pennsylvania | PA | 151850 | 7882 | 5.19 | 11860.962 | 615.660859 | 530.7 |
| %Deaths/million population for 7 states with highest deaths/million population | %Deaths/million population for 8-14th states with highest deaths/million population |
|---|---|
 |  |
US States confirmed cases vs political leaning
- For the political leaning see https://www.realclearpolitics.com/epolls/2020/president/2020_elections_electoral_college_map.html;
- For the Covid-19 deaths we use https://www.endcoronavirus.org/states and add the political leaning
| Candidate's states | Covid-19 confirmed cases/million population in states in western US | Covid-19 deaths/million population in states in western US |
|---|---|---|
| Solid Trump states |  |  |
| Solid+likely Biden states |  |  |
| Candidate's states | Covid-19 confirmed cases/million population in states in eastern US | Covid-19 deaths/million population in states in eastern US |
|---|---|---|
| Solid Trump states |  |  |
| Solid+likely Biden states |  |  |
Observations:
- Looking at the deaths/million population charts for the E US states there is a dramatic difference in the Biden vs Trump states. In particular for the Trump states the deaths/million population continue to climb while the Biden states have turned over and are increasing only slowly.
- For the confirmed cases/million population all curves in the Biden states exhibit a downturn in June - July that is not seen in the Trump states. The downturn persists for Vermont, Massachussetts, New York and New Jersey.
US States that were late in the application of Emergency measures
According to "Statewide Interventions and Covid-19 Mortality in the United States: An Observational Study" (see https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa923/5868545):
Later declarations of emergency and later school closure orders by a state were associated with higher state-level Covid-19 mortality in the United States, with each day of delay of either intervention increasing mortality risk by 5 to 6%. They tested the association between the timing of emergency declarations and school closures with 28-day mortality. Day 1 for each state was set to when they recorded ≥ 10 death. Nine states were identified as being late for Emergency contingencies: CA, CO, FL, GA, LA, NJ, NY, TX, WA. For schools add IN, IA, MO. Looking at the deaths/million population for these states we see two states (New York and New Jersey) with the pronouced flattening, the others do not see this.
Also see
- https://www.endcoronavirus.org/states for how well US states are doing in beating the Covid-19 virus.
- https://www.rand.org/pubs/tools/TLA173-1/tool.html for the Health and Economic Impacts of COVID-19 Interventions
"Social Distancing Interventions in the United States: An Exploratory Investigation of Determinants and Impacts"
paper by Shenyang Guo et. al to be found at https://www.medrxiv.org/content/10.1101/2020.05.29.20117259v1. The study has two findings: (1) states with a higher prevalence of Covid-19 cases per 10,000 population reacted more slowly to the outbreak, suggesting that some states may have missed the optimal timing to prevent the widespread of the Covid-19 disease; and (2) of nine mitigation measures, three (non-essential business closure, large-gathering bans, and restaurant/bar limitations) showed positive impacts on reducing cumulative cases, new cases, and death rates across states. The paper does not mention the wearing of masks.- "Statewide Interventions and Covid-19 Mortality in the United States: An Observational Study." See https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa923/5868545. Summary: Later declarations of emergency and later school closure orders by a state were associated with higher state-level Covid-19 mortality in the United States, with each day of delay of either intervention increasing mortality risk by 5 to 6%. Tested the association between the timing of emergency declarations and school closures with 28-day mortality. Day 1 for each state was set to when they recorded ≥ 10 death. Late states (9) for emergency CA, CO, FL, GA, LA, NJ, NY, TX, WA. For schools add IN, IA, MOs.