Scientists don't yet see signs that nationwide protests that began at the end of May accelerated the spread of the coronavirus. “It’s somewhat difficult to disentangle cases directly arising from the protests versus just opening up of society in general" in prior weeks, a Harvard epidemiologist told Scientific American. Mostly young protestors could in turn transmit the disease to older, more vulnerable family members, so an effect may yet be seen.
A study by San Diego State University found that “the protests had little effect on the spread of COVID-19 for the entire population of the counties with protests during more than two and a half weeks following protest onset.” They theorize that the protests may have on balance kept more people at home, offsetting increased risk of transmission in the streets.