There’s something wrong with America’s discussion about reopening.
Federal and state guidelines for reopening economies amid the coronavirus pandemic tend to frame recommendations in individual terms: This is what your school, restaurant, or bar should do to reopen safely — minimize capacity, stagger students or customers, encourage mask-wearing, and so on.
But some experts say these recommendations miss the point. Reopening is a community-wide project. Whether a school can reopen safely, for example, doesn’t just depend on capacity, personal protective equipment, or individual actions. It depends on how widespread the coronavirus is in the community outside the school’s walls.
Ashish Jha, the faculty director of the Harvard Global Health Institute, likened individual actions to putting up sandbags and other protective measures around a house during a flood. Yes, the sandbags can help. But if the water reaches a certain height, no amount of protective measures around the house are going to keep it safe.
“If the flood in your community is massive, there’s nothing you can do to keep the water out,” Jha told me. “So the first thing you want to do is make sure that the river doesn’t get too high. The second thing you can think about is how to protect your home.”
Coronavirus outbreaks play out in similar terms. Getting people to stay 6 feet from each other, wear masks, wash their hands, and stagger groups to keep overall numbers down helps. But if a community is flooded with infections, the chances are much higher that those infections will creep in no matter how many protective steps are embraced. The school or restaurant in question will become yet another place where people can meet and transmit the virus, and that will make the epidemic worse.
It’s this rationale that’s led some experts to frame reopening in more zero-sum terms — to argue that the most important thing we could do to reopen any particular place or venue is reduce community transmission.
In other words: If you want to reopen schools this fall, then you need to get the spread of Covid-19 down, as close to zero as possible, this summer. And that means opting not to reopen — possibly at all and definitely not at full capacity — restaurants, bars, nightclubs, or other places that will lead to significantly more coronavirus spread but have less value to society than schools.
“We need to recognize we won’t be getting back to normal for some time,” Helen Jenkins, an epidemiologist at Boston University who wrote about this concept in viral tweets, told me. “We need to recognize we’re going to have to make some sacrifices.”
One way to look at this, Jenkins said, is to imagine reopening as a budget. If the goal is to keep community transmission below a certain level, there are only so many places that can be opened before a jurisdiction’s reopening budget is spent. And each place that’s reopened, from parks to schools to bars, will likely increase transmission to some extent (though to different degrees — outdoor venues, for example, are generally safer than indoor ones).
That means establishing priorities: schools over bars and nightclubs, and major local employers over sporting events and movie theaters.
“Everybody’s been asking the question, ‘How do we open up schools safely?’” Jha said. “My argument’s been: Live in a community that doesn’t have a big disease outbreak. That’s how you open up schools safely.”
Individual actions help, but community transmission is key
It’s not that individual actions are worthless. Far from it: There’s solid and growing evidence that such steps, including wearing a mask, are key to mitigating coronavirus outbreaks overall. Experts say it’s important that individuals and places continue taking such measures.
But the most important consideration for any single place thinking about reopening may not be what steps it takes but how widespread the coronavirus is outside its doors. If 5 percent of a community is infected with Covid-19 at any given time — so there’s up to a 5 percent chance that anyone coming into a venue will be infectious — that’s, obviously, much worse than 0.1 percent of the community being infected and a 0.1 percent chance. (The math isn’t quite this clean in reality, but it gets the concept across.)
On the higher end of the spectrum, community transmission can even get so bad that almost nothing can stay open. If Covid-19 becomes so widespread in a community that simply interacting with anyone you don’t live with is too risky, then even relatively safe places, like beaches or parks, can start to pose a significant risk of transmission too.
“If we try to do everything, we can end up with a repeat of March,” Jenkins said. “And we end up with nothing, because we have to lock up everything again.”
This is why it can be misleading to draw comparisons between different regions reopening at different rates. For example, Denmark got attention after its schools and day care centers reopened without causing a spike in coronavirus cases. But Denmark has also experienced a relatively small Covid-19 outbreak — with almost one-twentieth the cases per person as the US, despite having nearly twice as much testing relative to its population. That makes it hard to say that reopening schools in the US would have the same effect.
Many people are probably already thinking in these terms to some degree, likely feeling safer eating at a restaurant in, say, Wyoming or Vermont than in a Covid-19 epicenter like Arizona or Florida.
But experts argue that policymakers, school administrators, and business owners should more explicitly operate under these terms when they’re making decisions about reopening.
“I get a lot of business folks who call me and say, ‘Here’s our testing strategy for employees. What do you think?’” Jha said. “But if you’re in Phoenix right now, you can have whatever testing strategy you want for your workers. It’s not going to do anything.”
Governments should think about reopening as a budget
One way to think about all of this is that each municipality, state, and country has a limited reopening budget.
The goal is to keep the basic reproduction number in a community below 1. That would mean that every person who gets coronavirus transmits it to, on average, fewer than one other person. Over time, that would lead to coronavirus cases falling closer and closer to zero. This number is typically calculated as the R0 or Rt, depending on the methods used. (Some websites, like Rt.live, calculate this figure for all states, and it’s at 1 or more in most states.)
Although different settings carry different risks, any place in which people who don’t live together interact likely increases the risk of Covid-19 transmission to some degree. Knowing that, different jurisdictions can only open a limited number of venues.
Some of that could come down to the effective “cost” — the amount of risk present in any given venue. For example, parks, beaches, and other outdoor places seem to carry a very small risk of coronavirus spread, thanks to the open air diluting coronavirus-infected droplets, wider distances between people, and, potentially, the ability of heat, UV light, and humidity to snare the virus.
Meanwhile, bars carry a large risk. They’re often cramped and poorly ventilated places where people can remain and possibly talk loudly — spreading droplets — for hours as drinking loosens their inhibitions. In the framework of the reopening budget, parks and beaches are cheap, and bars are expensive — so maybe it’s prudent to open parks and beaches first.
It can also come down to priorities. For example, schools likely carry some risk of Covid-19 transmission, as an indoor environment in which students, teachers, and other school staff interact for hours. But schools are also really important for day-to-day life — not just for kids’ education, but also for food, shelter, and child care while parents are at work. Knowing that, a community may decide to fit schools into its reopening budget. The trade-off would be that other places, such as restaurants, bars, or gyms, more likely have to remain closed.
Different communities could also prioritize different settings. If a specific factory is a big source of jobs in a city, maybe the local government there will deem it a priority even if it carries a certain risk of transmission. This is, in effect, what communities around the world have done as they deem certain goods and services “essential” and allow them to reopen or stay open.
On the flip side, certain measures — like aggressive testing, contact tracing, and isolating — may reduce the risk of transmission overall.
In practice, a budget can’t be perfectly allocated. We don’t have data to say, to use a made-up example, that restaurants at limited capacity add 0.5 to a community’s Rt, the factory adds 0.3, schools add 0.2, parks add 0.05, and the test-and-trace program subtracts 0.1 — making it safe to do all that and remain below an Rt of 1. We don’t know enough about the spread of Covid-19, and possibly never will, to make those kinds of granular determinations.
A more realistic implementation, instead, is to some degree what states are already doing: slowly reopening parts of the state bit by bit, giving each phase of reopening some time to gauge the full effects, and slowing down or reversing course if rates of infection increase.
“Since this is new and we don’t have data and experience to guide us, it makes sense to take things slowly,” Lauren Ancel Meyers, a mathematical biologist at the University of Texas Austin, told me. “Relax things bit by bit and see if it’s working. If we relax a few measures, we watch the data for a few weeks; if it’s not going up, maybe we can relax a bit more.”
Where thinking of this problem as a state budget comes in is that it can make priorities more explicit. So far, states have generally proposed broad plans in which they’re opening all parts of their economies, with the goal of returning to normal, or as close to normal, as possible — letting bars, sports, and other entertainment venues eventually open in some capacity.
But if you know you have a limited budget, and this budget is truly zero-sum, that can make your calculations about priorities more explicit. If bars or sports stadiums add far too much to the Rt, all while not serving as much value as schools, then the risk of opening bars and stadiums before the fall just isn’t worth it — because that could endanger the prospect of reopening schools by letting community transmission get out of control.
“We may just be at a point where we say during the pandemic we’re not going to have nightclubs,” Jha argued. “If we want nightclubs, we may not be able to get schools and other businesses open, or we’ll have to deal with hospitals getting full. That is the right way to think about it.”