In August, approximately 460,000 people converged on the town of Sturgis, South Dakota, to participate in the 2020 Sturgis Motorcycle Rally. After the event, the Minnesota Department of Health investigated a COVID-19 outbreak associated with the rally. Mayo Clinic microbiologists Joseph Yao, M.D., and Matthew Binnicker, Ph.D., served as two of the co-authors on that study.
A report summarizing the results was published in November on the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report. It stated that 86 cases of COVID-19 in Minnesota were found to be associated with the rally, and approximately one-third of Minnesota counties reported at least one case linked to the event. But it noted that the findings represent an underestimate of the event's COVID-19 impact in Minnesota and do not take into account its effect in other states.
The report also stated: "The findings suggest that this rally not only had a direct impact on the health of attendees, but also led to subsequent SARS-CoV-2 transmission among household, social, and workplace contacts of rally attendees upon their return to Minnesota. Whole genome sequencing results supported the finding of secondary and tertiary transmission associated with this rally."
It emphasized that the findings reinforce the importance of infection prevention strategies, such as avoiding large gatherings, mask use, social distancing, isolation of people with COVID-19, and quarantine for individuals who come in close contact with those who have the virus.