Epidemiologists believe that figure is a significant undercount, due to the resistance of some rallygoers to testing and the limited contact tracing in some states. As a result, the true scope of infections stemming from the event that ran from Aug. 7 to Aug. 16 is unlikely to ever be known. Public health officials had long expressed concern over the decision to move forward with the annual event, believed to be the largest held anywhere in the U.S. since the pandemic shelved most large-scale gatherings.
Now, just over two weeks after the conclusion of the rally, the Midwest and the Dakotas in particular are seeing a spike in coronavirus cases even as infections decline or plateau in the rest of the country. Besides the fallout from Sturgis, Ehresmann and other health officials attribute much of the increase in the Midwest to people not following public health guidelines, not wearing masks and attending social gatherings such as weddings and funerals.
But Sturgis was unique in drawing people from across the nation to one small town, where they crowded into bars, restaurants, tattoo shops and other businesses, many without masks. An analysis of anonymized cellphone data, conducted by a firm called Camber Systems, found that 61 percent of all U.S. counties had been visited by a rallygoer.
Those participants then returned home “perhaps to locations that weren’t seeing as much transmission to begin with,” Ehresmann said. “You have the potential to amplify transmission in multiple places. That’s what’s concerning from a broader public health standpoint.”
Of states that have reported rally-related infections, South Dakota has seen the most, at 105. State health officials there put out alerts about three potential covid-19 exposures that occurred while the event was underway, after learning that individuals who had tested positive for the virus had visited Sturgis businesses while infectious.