By Nedra Rhone | Atlanta Journal-Constitution | June 1, 2020 

As protests spilled into metro area communities this weekend, Atlanta Mayor Keisha Lance Bottoms offered demonstrators a few words of advice. “If you were out protesting, you probably need to go get a COVID test this week,” Bottoms said during a press conference Saturday evening.

Local and national health experts echoed the mayor’s concerns given some unknowns of how the virus might be transmitted.

“There is little that we know about how protests or events like these impact transmission,” said Emory infectious disease expert Dr. Carlos del Rio. “It is not good and it is not good for a variety of reasons.”

Sparked by the death of George Floyd, who died Monday after being pinned down by a then-Minneapolis police officer, protests in Atlanta and other major cities drew large crowds into the streets this past weekend. Hundreds gathered downtown and in other parts of the metro area linking arms, standing in close proximity and chanting or shouting. Some wore masks but many did not, raising concerns of how the protests may alter the trajectory of Atlanta’s COVID-19 transmission rates in the coming weeks.

For many people, the desire for public expression won out over the possible impact on public health. “You have a First Amendment right to be present in public spaces to express your views,” said Andrea Young, executive director for ACLU Georgia. “(Attending a protest) is an individual decision, but certainly we would always encourage people to follow the guidelines of science and health professionals when they are out in public. It is hard to say you should go to the grocery store but not follow your conscience when something is calling you to be present and stand for justice.”

Dre Propst, 51, a local activist who lives in Gwinnett County, said he thought carefully about his decision to attend the protest this weekend in Centennial Olympic Park. “I made sure I covered my face. I made sure I followed the guidelines from the CDC,” he said. Some organizations also posted guidelines for protesters, such as wearing masks, maintaining social distancing, limiting face-to-face conversations and making plans to quarantine for 14 days and get tested after attending an event.On Sunday, Scott Gottlieb, former commissioner of the Food and Drug Administration, warned that the national protests could lead to an uptick in coronavirus cases. “There’s going to be a lot of issues coming out of what’s happened in the last week, but one of them is going to be that chains of transmission will have become lit from these gatherings,” Gottlieb said on CBS News’ “Face the Nation.”

For months, researchers have studied how COVID-19 is transmitted, but what they know about the virus changes rapidly, said Dr. Jose Vazquez, chief of the Division of Infectious Diseases at the Medical College of Georgia at Augusta University. The virus is believed to spread primarily through respiratory droplets from close person-to-person contact even in people who do not exhibit symptoms. “We do think that aerosol transmission is the most likely route. Sneezing or coughing into someone’s face. Even when we talk, there are air particles that come out,” Vazquez said.

The farther those droplets travel, the fewer that remain in the air. “Within 3 feet is the danger zone. How long do we have to be within 3 feet? That we don’t know,” he said. “To me, (a protest) seems like an event where something is going to happen.”

Casual contact rarely leads to transmission, but there are a range of scenarios at a protest that may impact how the virus is transmitted. “It is not just the number of people but also the actions that may increase transmission,” del Rio said. “When you are screaming or shouting and you are infected, you are more likely to transmit. But you are outside and because you are outside, the likelihood of transmission decreases. The good news is you are outside; the bad news is that people are congregating and gathering and screaming and many of them are not wearing masks. That to me is concerning.” In order for transmission rates to be decreased, about 75% of people in a crowded environment would need to be wearing masks, del Rio said.

More than 1 million Americans have contracted COVID-19 since the first case was confirmed in late January, including more than 46,000 Georgians. There are signs that the number of cases and death counts may be leveling off, but that is not consistent across the country, according to health experts. Georgia has remained mostly the same from day to day, said del Rio, noting that there is more likely to be a second hump of infections than a second wave in the future.

In Atlanta, the number of COVID-19 cases has been flat but is having a slight, steady increase, del Rio said. The virus has an average incubation period of five days and as many as 14 days, he said, so any impact from the protests this weekend on infection rates would not be seen for at least another week. “This could potentially lead to transmission,” del Rio said. “We won’t know until it happens … but obviously the reality is that all of us that worry about transmission worry that this could happen.”