It's possible that the recent protests caused an increase in the spread of the coronavirus. But researchers haven't seen it yet, NBC reports. A study published Wednesday by the National Bureau of Economic Research considered data from 281 cities that have had protests and 34 that have not. "When we look at the population of the counties as a net, there does not seem to have been significant community spread," said one of the study's authors, a professor, "and no significant increase at all in overall cases at the population level." Health officials in New York and Philadelphia said they haven't seen an increase since the protests began. Researchers used data from the Centers for Disease Control and Prevention and SafeGraph, which tracks people's movements through their cellphones. The study has not been peer reviewed yet.
The researchers have a theory, which an outside expert at Emory University in Atlanta supported: People who were not taking part in the protests started staying at home more, which could have canceled out an increased spread among the crowds in the streets. "There are other possible explanations for our findings as well, such as avoiding travel outside the home due to additional traffic congestion or street closures, or due to lack of available activities from businesses closures near protest sites," the study says, per CNN. It's also possible the protests still will lead to more infections; Dr. Anthony Fauci has said it takes at least three weeks for the number of coronavirus cases to be affected by a change in behavior, such as gathering in large crowds. (Read more coronavirus stories.)