The Slatest

How Much Should You Be Worried About a COVID-19 Spike From the Protests?

A man in a crowd wears a mask that says "I can't breathe."
A man attends a vigil for victims of police violence in Tacoma, Washington, on Wednesday. Jason Redmond/Getty Images

The nation is entering its second week of mass protests over police violence and the brutal killing of George Floyd. While most Americans agree with the protesters’ cause, some detractors worry about the cities with the largest marches, where people are gathering in the thousands in the middle of the COVID-19 pandemic.

Those arguments aren’t  always made in good faith, but the concerns have some validity. How big is the risk that the protests could set off a new wave of infections across the country?

“We should be worried,” said Shira Shafir, an associate professor of epidemiology at the UCLA Fielding School of Public Health. “Any time now we see people who are not maintaining social distancing, there’s the potential for those people to spread the virus. But by the same token, I think we’re currently facing two public health crises. The first is COVID. And the second is racism and police violence that we’ve been facing for centuries.”

As tens of thousands of Americans have taken to the streets in recent days, transmission of the coronavirus is still rampant across the U.S. Anyone joining the protests should be aware that there is a risk. But that isn’t an argument for people to stay home. As many scientists and doctors have agreed—and as the protesters themselves have argued—police brutality against the black community is its own urgent health crisis. And it’s not lost on the protesters that the same community already so devastated by the pandemic is now most likely to suffer from the virus’s spread at the protests. Those demonstrators have chosen to take on the risks from the coronavirus pandemic because they have decided that the public health risks from police brutality are more urgent and immediate.

Still, it’s hard to say exactly how risky these demonstrations are. There are conflicting sets of factors that make it hard to tell what to expect in the coming weeks.

Decreased risk

Open-air setting: Being outside could be the saving grace for the protests. There is a consensus among scientists that the outdoors are far safer, in part because a breeze can dilute the virus, meaning you don’t get as much of a viral load hitting your immune system at one time. But there’s still risk if you don’t keep distance from others around you, and ultimately, hundreds and sometimes thousands of people are still packed together, sharing a lot of the same air.

Summer temperatures: There’s some evidence that the virus doesn’t spread as well in hot and humid environments, possibly because it breaks down under the heat and particles fall to the ground more quickly in humidity. But that evidence comes from lab settings and from historical trends for influenza and other seasonal viruses, and neither form of evidence is conclusive. Plus: hot, humid places such as Brazil have had major outbreaks, so any mitigation from the summer climate is likely to be very modest.

Frequent mask use: Mask use has been common, though not universal, among protesters. But there’s a reason masks have sparked as much debate as they have: We continue to be uncertain just how effective they are. The body of research generally supports the belief that they help slow the spread by reducing how far, and in what quantity, droplets travel, but it’s hard to say by how much.

Increased risk

Densely packed crowds: This is the main reason to worry. “It’s kind of a setup for viral transmission,” said Peter Chin-Hong, an infectious disease specialist at the University of California, San Francisco. “People trumps everything, every other environmental factor. So it doesn’t matter if it’s hot, it doesn’t matter if it’s sunny, with UV lights. As long as enough people are there, the virus is happy, because it’s trying to jump from somebody’s nose or mouth into somebody else’s nose or mouth.”

The danger varies by location, though. In a place such as Los Angeles, where COVID-19 cases are still quite high, having large gatherings is more likely to spread the virus than in a place like Portland, Oregon.

Shouting, chanting, and singing: Any time a person projects their voice—to shout the names of those killed by police, for example—the particles that could carry the virus travel farther. As a result, some health experts recommend people use megaphones to magnify their voices and rely more heavily on signs to spread their message.

Holding cells: In many cases, police have arrested protesters and driven them in vans to be held in jail cells. Jails are notorious for spreading the coronavirus by forcing people into a cramped, enclosed space, which researchers agree is the worst setting for spreading the coronavirus. A high volume of arrests—and therefore higher turnover rate in any given cell—would also mean those held in jail are exposed to more people than usual. “You’re making people vulnerable, inherently,” said Yamilé Molina, a health disparities scientist at the University of Illinois at Chicago School of Public Health.

Tear gas: According to public health experts, one of the worst ways police endanger protesters at these marches is by firing off tear gas. Tear gas causes everyone in the affected area to cough—a common way of spreading the virus. “Using tear gas is probably one of the worst things you can do for COVID transmission,” Chin-Hong said. “It allows more coughing and makes it easier for the virus to potentially infect the nose in the mouth and get into the lungs potentially, because it’s acting as an irritant.” Molina added that people often respond to tear gas by helping one another with medical care, putting them in close contact. “When they’re clustering together, the worst thing we can do is attack their respiratory system simultaneously,” Molina said. The good news is that eye protection, which can help protect protesters from tear gas, does double duty as a measure against COVID.

Demographics: At first glance, the youthfulness of the crowds could be seen as a blessing, given that these protesters are less likely to fall seriously ill. But they are also more likely to be asymptomatic carriers and spread the virus without realizing it, and that’s worrying, said George Rutherford, the head of the infectious disease and global epidemiology division at the University of California, San Francisco. Then there’s the matter of race: Rates of infection are higher in black communities, which are also leading and heavily populating these protests.

But even when factoring in all these conditions, it’s still very difficult to say how we should think about the protests. “There’s no sort of magical calculator that we can put this into and say the risk of someone getting infected is X,” Shafir said. “All we’re able to do is look at the different pieces and say, ‘Masks are better, but coughing and yelling are worse.’ ”

The health experts agreed that rather than worry about the chances of getting COVID-19 from the protests, participants should think about precautions. While a protester can’t do much about the police officers’ decision to use tear gas or place people in jail, individuals can help protect themselves by wearing masks, carrying hand sanitizer, and mingling with the same group of other people—think of it as something like a protest “bubble”—through the process. When they get home, they should wash their hands, wipe down their phone, disinfect their belongings, wash or dispose of their mask, and shower. And when people are done protesting, they should self-quarantine, if possible, and get tested.

“Ultimately, it points to what a crisis this is, that people do acknowledge and do understand that there is a chance they are going to get infected with COVID,” Shafir said. “While there is absolutely the possibility or even the probability that this virus will be transmitted by individuals who are exercising their right to protest, I think they have to be allowed to do so. And encouraged to do so.”