First Look at Sturgis Super Spreader MC Rally

It’s now been about 3 weeks since the start of the annual motorcycle rally in Sturgis, SD, which lasted from August 7-16 and drew an estimated 460,000 attendees this year — with very little evidence of face masks or social distancing.  Nearby states are already linking dozens of new Covid-19 cases back to Sturgis, so the question becomes whether we can actually see such a signal emerging from the weekly new case data for South Dakota and surrounding states yet. 

Toward that end is a table listing the day-by-day weekly totals for those 7 states, as well as the USA as a whole, all normalized to reflect the 7-day new case totals per 1 Million population, together with a baseline trend from July 30 — August 13 (2/4 Wks), and the trend from today relative to 2 weeks ago (0/2 Wks) in which we would expect to see the start of any true signal. 

The first thing to note is that while it is still too early to see much evidence of any signal in NE, MT, or WY yet (the latter of which still has too few weekly new cases to provide any meaningful trend analysis), and only the hint of an emerging signal in MN, there is already a clear signal present in ND and IA, and an absolutely screaming signal in SD itself.  Indeed, up until about 10 days ago, total new covid-19 cases had been averaging well under 700 per week there, but have now spiked to over 1,500 in the past week (with 623 today alone).

So taking into account both the pre-Sturgis baseline trends and the overall downward trend in the USA as a whole over the past month, we could be looking at well over 1,000 new cases attributable to Sturgis already in SD, and possibly hundreds of others in ND and IA.  Those familiar with my analysis of the Tulsa Super Spreader Event may recall that it took at least 3 weeks for the signal in OK to become manifest, so if we’re seeing this strong a signal this relatively soon after Sturgis, this really could turn out to be a real monster of a super spreader with an ultimately national impact.

Sturgis Effect thru August 27

	USA	SD	ND	MN	IA	NE	WY	MT
0/2 Wks 2/4 Wks 8/27 8/26 8/25 8/24 8/23 8/22 8/21 8/20 8/19 8/18 8/17 8/16 8/15 8/14 8/13 8/12 8/11 8/10 8/09 8/08 8/07 8/06 8/05 8/04 8/03 8/02 8/01 7/31 7/30	-22% -18% 907 905 906 917 929 942 968 999 1,029 1,057 1,089 1,109 1,148 1,150 1,159 1,168 1,171 1,178 1,166 1,164 1,177 1,200 1,225 1,269 1,293 1,335 1,355 1,382 1,405	141% 15% 1,699 1,136 1,200 1,204 1,133 1,150 972 897 849 825 788 756 725 738 705 731 717 727 735 689 686 665 596 664 651 633 635 638 613	57% 23% 2,045 1,967 1,899 1,776 1,692 1,696 1,512 1,406 1,310 1,177 1,226 1,301 1,228 1,306 1,304 1,198 1,249 1,218 1,228 1,189 1,126 1,150 1,089 1,039 1,049 1,029 1,136 1,122 1,060	17% -12% 901 819 824 812 786 790 782 765 765 749 745 754 765 805 772 802 829 879 878 871 837 877 857 865 843 850 868 882 881	84% -11% 1,750 1,559 1,369 1,246 1,217 1,237 1,288 1,234 1,106 1,149 1,155 1,142 1,120 967 952 997 1,040 1,022 1,034 1,012 1,046 1,050 1,069 1,035 1,042 1,065 1,081 1,044 1,073	-5% -6% 906 872 787 767 784 796 847 873 929 928 965 1,003 1,105 974 951 1,068 958 900 895 886 979 1,063 908 1,045 1,064 1,078 1,032 1,053 1,007	58% -53% 439 439 468 470 506 546 589 603 594 501 485 408 370 316 278 282 326 349 418 421 473 470 509 509 566 575 558 554 587	6% -11% 803 777 729 653 636 672 632 623 644 695 726 747 721 734 754 786 740 734 711 757 742 738 705 786 798 797 769 867 847

As usual all data derived from worldometer