The Case of Trump Rallies
A group of researchers from Stanford University explored whether or not the large outdoor rallies (that are characterized by few if any mitigation measures) contribute to community spread after the events. They looked at 18 Trump campaign rallies to determine whether there was a subsequent rise in COVID-19 cases in those jurisdictions relative to control (placebo) jurisdictions that didn’t have a rally.
They used a collection of regression models to capture the relationships between pre and post-event outcomes including demographics and the trajectory of COVID-19 cases in matched counties. The regression models showed that COVID-19 cases increased by more than 250 per 100,000 residents following the rallies.
Extrapolating this figure to the entire sample, the report concludes that “these eighteen rallies ultimately resulted in more than 30,000 incremental confirmed cases of COVID-19. Applying county specific post-event death rates, we conclude that the rallies likely led to more than 700 deaths (not necessarily among attendees)“.
They conclude that: “Our analysis strongly supports the warnings and recommendations of public health officials concerning the risk of COVID-19 transmission at large group gatherings, particularly when the degree of compliance with guidelines concerning the use of masks and social distancing is low. The communities in which Trump rallies took place paid a high price in terms of disease and death.”
Remember- this isn’t a peer reviewed article and has not been published except by the authors. In general, I’m reluctant to draw firm conclusions about cause and effect like this unless the work is published in a reputable peer-reviewed journal. However, it does make some intuitive sense that the rallies are likely contributing to community spread because few if any mitigation measures are adhered to at these events.