The Sturgis Motorcycle Rally in South Dakota, which took place from Aug. 7-16, acted as a "superspreader event" for COVID-19, according to a discussion paper published by the IZA Institute of Labor Economics that has sparked backlash from the state's governor.
The authors studied the 10-day event, which drew more than 460,000 individuals to a city with a population of about 7,000, according to the paper. The authors said media reports suggest social distancing and mask-wearing recommendations were not heavily followed at the rally.
The authors said the event increased COVID-19 cases in South Dakota's Meade County, where the event took place, by 6.3 to 6.9 cases per 1,000 as of Sept. 2. South Dakota as a whole saw a 35 percent increase in cases a month after the event when compared to cases on July 31, the paper said.
The researchers concluded the Sturgis rally may have generated at least $12.2 billion in public health costs. However, Devin Pope, PhD, a professor of behavioral science and economics at the University of Chicago, tweeted Sept. 8 that he would "suggest caution in terms of running with numbers like the Rally had 'public health costs of $12.2B.'" He added that, "Overall, I think the 'Sturgis Effect' that the authors document is in large part just a Midwest surge that took place during this time period. There is likely still a small Sturgis Effect (for example, Meade county looks especially bad), but the results are likely biased upward."
South Dakota Gov. Kristi Noem called the study "grossly misleading" and said that "modeling isn't reality" in a Sept. 8 statement.
"This report isn't science; it's fiction. Under the guise of academic research, this report is nothing short of an attack on those who exercised their personal freedom to attend Sturgis," Gov. Noem said. "At one point, academic modeling also told us that South Dakota would have 10,000 COVID patients in the hospital at our peak. Today, we have less than 70. I look forward to good journalists, credible academics, and honest citizens repudiating this nonsense."