SEATTLE—Strips of red tape, six feet apart, line the sidewalk outside the walk-up window at Chocolati Cafe. Business is steady on this sunny Sunday, despite the tables and chairs stacked up inside. Three baristas scramble to keep up with orders from an array of customers that stretches out more than 30 feet.

Geordie Glass has just ordered his eight-ounce latte. He’s on his way to walk a lap of Green Lake across the street. “I do this almost every day now,” Glass, 45, told The Daily Beast. “I’m running out of things to do at home.”

At the lake, a steady stream of walkers, runners, skaters, and bikers share the three-mile path with gaggles of geese. Here, too, most people—if not the congregating geese—are adhering to the international trend toward social distancing.

A reminder is posted by the trail: “Stay 6 feet or at least arm’s length away from others.”

But what was a sort of Northwestern curiosity as recently as a few weeks ago may not only outlast the wishes of GDP-fixated politicians like Donald Trump, but also become a regular—that is, intermittent—fact of American life. Taken together, recent COVID-19 forecasts suggest Americans should be ready not just for a months-long shutdown, but also to potentially return to the practice again.

In other words, some epidemiologists and other scientists closely studying the pandemic increasingly seem to be veering toward a long-term, multilayered approach—including repeated periods of social distancing.

“It’s like a fire. If you don’t completely put it out, it will come back. You have to keep suppressing it,” Michael Osterholm, professor and director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told The Daily Beast.

More than 250 million Americans have been ordered to “shelter in place” or stay at home in hopes of quelling COVID-19. Washington Gov. Jay Inslee (D)—whose initial order in America’s first state with a confirmed case of the disease was set to expire on April 8—said last week that the effort would be extended. He and local authorities have also introduced piecemeal measures: In addition to schools, dine-in restaurants, bars, and other nonessential businesses, closures now include many trailheads, playgrounds, even boat-launch sites.

New data suggest the social-distancing efforts have slightly slowed the rate of increase in new COVID-19 infections across the state—that there’s hope here. “We have to hammer this until we can be assured it will not spring back up,” Inslee said.

But just how hard and how long to hammer remains up for debate. A pair of reports released Monday by the Bellevue-based Institute for Disease Modeling found that social-distancing policies have curtailed the movement of people around King County, Washington, and significantly slowed the spread of COVID-19. Still, the models suggest “evidence of fluctuating adherence” leaves the county in a “precarious position,” according to its authors.

That data followed analyses released Thursday by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington’s School of Medicine. As of Tuesday, it forecast U.S. deaths to total more than 83,000 by July, even with social-distancing measures in place. “It’s working and it will work even better if we do much more of it,” Ali Mokdad, a scientist at IHME and contributor to the analyses, told The Daily Beast. “In many places, even in Seattle, people are not 100 percent adherent to staying at home. We have to stay vigilant at least through mid-May.”

Even that may not be enough. Still more research released last week by a Harvard team suggested a successful battle against COVID-19 was also unlikely to be waged in a single shot.

The authors of the paper, a preprint posted at medrxiv.org that hasn’t yet been peer-reviewed, determined that one long period of stringent social distancing could potentially backfire in a greater resurgence of infections come fall and winter, unless other interventions are put in place. The finding was consistent with the course of the 1918 influenza pandemic, during which cities that had low peaks during the first wave of infections—thanks in large part to social-distancing measures—were at a greater risk of a higher second wave after those interventions were lifted.

Models detailed in the Harvard paper point to cycled periods of social distancing as a potentially better way to minimize the overall toll on the population, achieve greater “herd immunity,” and take pressure off already-strapped intensive-care units (ICUs).

The approach may also provide a welcome summer respite for Seattleites, New Yorkers, and other Americans who are going stir crazy—or facing economic hardship, large or small. “Any kind of reprieve would be welcome,” said Glass, who works as a physician assistant in radiology—now 30 hours a week due to reductions in elective surgeries in response to the pandemic. Millions of Americans have lost their jobs entirely, and millions more are expected to in the coming days.

Rather than fully releasing the brakes, according to the Harvard models, officials may eventually want to start pumping them—strategically letting up on social distancing as ICU beds empty, and then re-enacting measures as beds fill back up. The idea, in part, would be to steadily build up population immunity while not overwhelming critical-care capacity.

“What we find is that those social-distancing efforts that are relatively successful in flattening the curve end up pushing the peak out,” Yonatan Grad, an infectious-disease expert at the Harvard T.H. Chan School of Public Health and a co-author of the paper, told The Daily Beast. “If there is seasonality, and if the peak gets pushed into the fall, we will see an even higher peak.”

Seasonal changes in temperature and humidity, as well as a return to school and indoor crowding during cooler months, are among factors that may increase transmission of the virus. Grad said the best-case scenario, based partly on achieving an optimistic doubling of ICU capacity, would mean social-distancing measures need to be in place 25 percent of the time over the next nine to 10 months. The worst-case scenario, according to the models, is two years of cycled social distancing.

Suffice it to say that might be a tough sell. “The public’s acceptance of this kind of a shutdown two or three times does not seem likely,” said Howard Markel, director of the University of Michigan’s Center for the History of Medicine.

The models highlighted by Grad assume that the spread of COVID-19 will slow during summer months, as it did for SARS, a previous coronavirus. (While scientists suspect that seasonality is again likely with this virus, they currently lack the data to be certain.) Improved capacity for testing and containment should also lessen the need for social distancing—as would treatments or dissemination of a safe and effective vaccine, the ultimate goal, which isn’t expected for perhaps 18 months.

“We’re buying time until a vaccine,” said Juliette Kayyem, faculty chairwoman of the homeland security project at Harvard’s Kennedy School of Government. “Social distancing is to get on the other side of the curve, then we can begin mitigation efforts. We need a multilayered approach to managing living with the virus during this time.”

Kayyem underscored another limitation of the models: They assume a “united social distancing effort,” which is far from the case in the U.S., where some states and communities are trying different combinations of interventions—if any — at different times.

Overall, mathematical models “need to be seen with great caution, especially when epidemics are modeled,” noted John Ioannidis, an epidemiologist at Stanford University, in an email to The Daily Beast. He, too, underscored the unknowns. If any one of a number of assumptions made by the Harvard researchers turn out to be wrong, he said, then their models could “collapse entirely.”

Before determining next steps, such as whether or not to stop lockdowns or social distancing measures, added Ioannidis, more unbiased data is needed on COVID-19, including its true incidence, fatality rate, and the proportion of infected people needing hospitalization.

Another remaining open question is whether or not people who recover from the virus could be susceptible to it later on. “We should not yet count on herd immunity,” said Mokdad. “We should count on social distancing. It will help us now and in the future.” His IHME team has not yet modeled the potential resurgence of the virus. “It’s on our to-do list,” he said.

Meanwhile, the diversity of responses to COVID-19 both around the world and within the U.S. could itself provide useful information. Successful efforts in China, for example, have left a large population susceptible to the virus. How will that country fare in the months ahead? Will they face a resurgence of infections? On Friday, authorities once again closed all of China’s movie theaters, which had recently reopened after a two-month shutdown. The move has triggered speculation of a possible second wave of infections.

“One of the things that needs to happen now is a better understanding of which social-distancing measures actually worked and how well,” said Grad, noting that sufficient data was still several weeks away. “Does it matter if we close schools? Or large sporting arena events? Or is what really matters getting rid of bars and restaurants and preventing even small groups from mixing?”

How about the impact of the selective measures instituted at a place like Green Lake Park? A sign attached to a barrier that blocks entrance to one of the Green Lake parking lots explains that the closure is “to reduce park use and help slow the spread of the COVID-19 virus.” Along the lake’s perimeter, yellow tape wards people away from a children’s playground, exercise equipment, and swimming pool. Tape also spans from hoop-to-hoop down the length of an outdoor basketball court; the park’s tennis courts remain open and in full use.

On top of protecting the population, maintaining social distancing now will provide the time and data to fully investigate these questions, Grad argued. Such answers, which he noted will likely vary across communities, should not only help in choosing effective measures when they need to be implemented again, but could also inform how we emerge from social distancing.

“There’s a smart way to do this that does not just involve stopping everything at once,” he added.

Osterholm, the professor at the University of Minnesota, underscored the need to find a middle ground between suppressing infections completely for an extended period of time and letting the virus run its course through the population. Toward that end, he urged taking a “Manhattan Project-type approach”—bringing the best minds together to come up with a national plan, as soon as possible.

Repeated periods of social distancing might not be popular. But neither would “promoting an 18-month total lockdown of the country,” he told The Daily Beast. “So, how do you try to thread a rope through this needle?”

If nothing else, messaging from on high teasing a longer timeline—and warning that more concerted shutdowns may be coming—could help the public wrap their heads around the idea.

“If it was planned, that would help a lot. Then I could take time off from work, arrange childcare,” said Glass, of the potential for intermittent social distancing. “No one was prepared for this. They just said, ‘By the way, starting tomorrow, you can’t go out.’ That was pretty hard.”