Protests in top 25 virus hot spots ignite fears of contagion

In this Saturday, May 30, 2020 photo, police officers guard the Trump International Hotel & Tower in Chicago, as they hold back protesters during a rally and march over the death of George Floyd. Protests were held in U.S. cities over the death of Floyd, a black man who died after being restrained by Minneapolis police officers on May 25. (John J. Kim/Chicago Tribune via AP)

PROVIDENCE, R.I. — As demonstrators flooded streets throughout America to decry the killing of George Floyd, public health experts watched in alarm — the close proximity of protesters and their failures in many cases to wear masks, along with the police using tear gas, could fuel new transmissions of the coronavirus.