None of the plans for how the nation might safely emerge from the coronavirus lockdown involved thousands of Americans standing shoulder to shoulder in the streets of major cities or coughing uncontrollably when the authorities used tear gas to disperse them. No one planned on protesters being herded into crowded prison buses or left in crowded cells.
Before the eruption of outrage over the killing of George Floyd in police custody in Minneapolis, debates about reopening centered on whether states had adequate systems in place to detect and treat cases of the coronavirus, which has killed more than 110,000 people in the United States since the beginning of the year.
But as the protests against police brutality continue for a second week, public officials are warily watching for signs that an unanticipated end to social distancing on a mass scale has led to new cases of the virus. The question has become part of the politicized debate over the economic repercussions of the lockdown, which some critics have argued went too far.
And on Sunday, infectious disease experts on Twitter debated how to supply a reliable estimate of the impact of the protests on virus transmission — or whether trying to do so may wrongly be seen as discouraging participation in the growing racial justice movement.
In what he called a back-of-the-envelope estimate, Trevor Bedford, an expert on the virus at the Fred Hutchinson Cancer Research Center, wrote on Twitter that each day of protests would result in about 3,000 new infections. Over several weeks, as each infected person infected just under one other person on average — the current U.S. transmission rate — those infections would in turn lead to 15,000 to 50,000 more, and 50 to 500 eventual deaths. Given the racial disparities so far in the pandemic, he noted, those deaths will be disproportionately among black people. “Societal benefit of continued protests must be weighed against substantial potential impacts to health,” he wrote.
Marc Lipsitch, an epidemiologist at Harvard, agreed that those projections were reasonable, and said in an email that Dr. Bedford had done “a service” by making an approximate estimate with explicit assumptions.
But he also noted that if states where the virus was still spreading managed to rein it in, that would “massively overshadow the effects of the protests.” About 20,000 new cases are identified across the country on most days, and about 1,000 new deaths are announced. If all communities were performing enough tests and contact tracing to bring down those numbers, fewer of those acquiring infections at protests would infect others, shortening the transmission chain and reducing the number of eventual deaths.
Dr. Bedford wrote that his estimates contained a lot of uncertainty. There is no official estimate for how many people are protesting on an average day, for instance. Still, he thought it was important, he said, to provide a framework grounded in epidemiologic principles to counter the offhand assumptions being made by political pundits. But, in response, other scientists voiced concern that Dr. Bedford’s posts would “give fodder to those opposing civil rights.”
Many epidemiologists, including Dr. Bedford, have noted in recent days that America’s entrenched racial inequalities themselves translate into disproportionate early deaths and illness among African-Americans. That has been especially evident in the coronavirus pandemic, in which black Americans are dying at about twice the rate of white Americans. A group of more than 1,000 people working in health and medicine signed a letter recently that said protests were, in fact, vital to public health.
“Racism and police violence are major threats to public health in this country, and protest is one of the only options available to people who have been systematically disenfranchised,” said Eleanor Murray, an epidemiologist at Boston University.
Because it can take up to two weeks for a newly infected person to show symptoms and the protests started shortly after Mr. Floyd’s death, health experts expect that any increase in cases will begin to surface this week. Demonstrators in several places have contracted the virus, including in Lawrence, Kan., where someone who attended a protest last weekend tested positive on Friday. That person did not wear a mask while protesting, local officials said. In Athens, Ga., a county commissioner who attended a protest said that she had tested positive.
In Oklahoma, a college football player who participated in a demonstration revealed that he later tested positive for the virus.
“After attending a protest in Tulsa AND being well protective of myself, I have tested positive for Covid-19,” Amen Ogbongbemiga, a linebacker at Oklahoma State University, wrote on Twitter. “Please, if you are going to protest, take care of yourself and stay safe.”
Many did their best. In Califoria, Jarrion Harris, 32, wore a cloth mask for a march in Hollywood on Sunday.
“I’m definitely not out here because I think Covid-19 has gone into the shadows,” he said. “It’s worth the risk.”
Politicians and public health officials have urged demonstrators to wear face coverings and to maintain social distancing. In some places, including Atlanta, Illinois, Los Angeles and Minnesota, officials have also urged protesters to seek coronavirus tests to make sure they have not become infected.
The surge of protests throughout American cities and the seeming support of some political leaders have not gone unnoticed on the right. Pundits and commentators have made the point in recent days that mayors and governors who sternly warned against public gatherings are now giving their blessing to the protests.
Dr. Tom Frieden, the former director of the Centers for Disease Control and Prevention who was appointed by President Barack Obama, tweeted last week that the threat to controlling the coronavirus was “tiny” compared with the threat “created when governments act in ways that lose community trust.”
That struck Jonah Goldberg, a writer for The Dispatch, an online conservative magazine, as an unfair double standard.
“You know what erodes public trust in people like Frieden?” Mr. Goldberg wrote. “When they say that you’re a fool or monster who will get people killed for wanting to go to church or keep your business open but you’re a hero when you join a protest they approve of.”
As the virus has spread across the country, many conservatives have rebelled against the stringent measures supported by public health experts, and there have been skirmishes over wearing masks in public, allowing in-person religious services and placing a premium on restoring the economy over other concerns.
If the virus surges again, said Christopher F. Rufo, director of the Center on Wealth and Poverty at the Discovery Institute, a conservative think tank, the experts’ standing will have been undermined. “You’re going to have half the country that has lost faith almost completely in the public health establishment,” he said.
But it may be hard to trace infections to other protesters, who are often marching side by side with strangers. And infectious disease experts have said that any increase in cases may well be the result of the continued reopening of restaurants, workplaces and mass transit.
In Las Vegas, casinos are reopening. In New York City, long the center of the coronavirus outbreak in the United States, as many as 400,000 workers on Monday can begin returning to construction jobs, manufacturing sites and retail stores as the city enters the first phase of its reopening.
“You cannot pin this on the protests,” said Jeffrey Shaman, an epidemiologist at Columbia University, whose projections of the virus’s path suggest that U.S. coronavirus deaths will increase in the coming weeks. “The protests are not in and of themselves going to drive the resurgence in cases. This is associated with all the new opportunities that are providing a way for people to get together and pass the virus to one another.”
For their part, activists said the drive to protest in the face of the virus reflected the larger gravity of the moment and the intensity of their passion.
“If I get infected fighting for justice, my soul can sit with that,” said Sara Semi, 27, a protester in Minneapolis who wears a mask with a filter and carries cans of disinfectant spray. “I can’t sit at home protected by my privileges if others aren’t. I can’t sit inside my house safe while my friends and neighbors are not. Yes, corona is happening. It’s real, it’s deadly. But racism kills way more lives.”
Vidal Guzman, 29, a protester in New York, said: “People are more scared of the police than Covid-19. They are willing to do anything.”
Different conditions and the many remaining unknowns about how the virus is transmitted can make it difficult to predict the spread of the virus at any given protest. Outdoor gatherings are much lower risk than indoor ones. How many people are wearing masks, whether they are shouting or using noisemakers and even the weather may all affect the risk of infection.
Still, expert say it is within the power of law enforcement authorities to minimize or eliminate some of the chief risk factors, like arrests and tear gas. And they add that protesters, if they choose to take to the streets, should do everything they can to stay safe.
“If you attended a protest,” Gov. Andrew M. Cuomo of New York said on Sunday, “assume you may have been exposed to Covid. Get tested.”
Mitch Smith, Sabrina Tavernise, Anjali Tsui, Jill Cowan and Kimiko de Freytas-Tamura contributed reporting.