Discussion paper: Sturgis rally caused spread of coronavirus

The controversial paper gave a “ballpark estimate” that 19% of new cases in the US between August 2 and September 2 were a result of the rally.

Harley Davidson motorcycle enthusiasts (photo credit: AP)
Harley Davidson motorcycle enthusiasts
(photo credit: AP)
An IZA Institute of Labor Economics Discussion Paper suggests that the 80th Annual Sturgis Motorcycle Rally held in August caused the spread of coronavirus locally and in home counties of non-local attendees. According to the paper, “the spread of the virus due to the event was large.”
The paper by the Bonn-based private and independent institute concluded that the rally generated substantial public health costs estimated at several billion dollars, giving a “ballpark estimate” that 19% of new cases in the US between August 2 and September 2 were a result of the rally.
The study further estimated that the Sturgis event caused an increase from 6.3 coronavirus cases per 1,000 to 6.9 cases per 1,000 in Meade County, South Dakota, where Sturgis is located, and an increase from 3.6 to 3.9 cases per 1,000 in the state.
The report also found that following the rally, counties with large numbers of people who attended saw a 10.7% increase in coronavirus cases relative to counties with no detected event attendees.
It found that states with strict coronavirus policies were able to mitigate potential Sturgis rally infections.
The study set out to examine the rally as a potential superspreader event for the coronavirus. Researchers identified it as such because the event was prolonged, included individuals packed in close proximity to one another, drew a large non-local population, and had “low compliance with recommended infection countermeasures such as the use of masks.”
South Dakota Governor Kristi Noem said that the paper is “fiction,” and an epidemiologist for South Dakota’s Department of Health said that the paper does not correlate with data inside the state and that it has not been peer reviewed, according to Keloland Media.
Kurt Cogswell, a math professor from South Dakota State University's data science department, told Keloland Media that the paper is “directionally correct in terms of no spread to some.”
Cogswell went on to say that the paper used the best data available and is a typical economic analysis in which available data is combined with assumptions in order to produce the report’s conclusions.
Cogswell said that IZA researchers were “very clear about their data,” and “very clear about their assumptions.”
The study itself states that “IZA Discussion Papers often represent preliminary work and are circulated to encourage discussion. Citation of such a paper should account for its provisional nature. A revised version may be available directly from the author.”