If you don’t like that you may have to stay home and avoid parties for the next few months to avoid spreading the coronavirus, you can blame, at least in part, poor policy in pandemic preparedness.

A major coronavirus epidemic in the US was always likely to require some social distancing. But experts say that failures in coronavirus testing and Covid-19 surveillance in general have exacerbated the country’s need for and reliance on social distancing — making it all the more important for individuals to get this right and follow best practices.

“Without surveillance, we don’t even know where to look,” Nathan Grubaugh, an epidemiologist at Yale University, told me. “We don’t even know where to employ self-isolation or social distancing. So now we’re stuck in this situation where it’s pretty much everywhere, and so we have to apply these methods across the board.”

Over the next few months, Americans are going to have to spend a lot more time at home. They’ll have to avoid bars, restaurants, and large social gatherings. In fact, they probably won’t even have the option to go to those places, as events across the country get canceled, restaurants temporarily close, and workplaces shut down their offices and tell employees to work from home. Experts say this will likely be needed not for days or weeks, but months.

Yet we still don’t know how extensive Covid-19, the disease caused by the novel coronavirus, is across America. As President Donald Trump’s administration has failed to roll out widespread and accessible testing, America has lagged behind its peers in the amount of tests being done. So even though there are more than 10,000 confirmed cases of coronavirus in the US as of March 19, experts and officials caution that there could, in reality, be five, 10, even 50 times more than that — we just don’t know. And we don’t really know where the worst outbreaks are happening and which areas are most vulnerable.

That means some of the crucial public health tools we should have to fight a pandemic — surveillance, contact tracing, and targeted quarantines — just aren’t currently available. So we’re now all-in on social distancing to stop the spread of Covid-19.

It’s in this context that Americans are being asked to stop physical contact with as many people as possible. Since we don’t know who has Covid-19 and which communities are at greatest risk, it’s best to play it safe and physically isolate everyone. The goal here is to “flatten the curve” — to spread out the spread of coronavirus to avoid overwhelming health care systems. We need to do this until scientists develop a vaccine, which could take as long as 18 months, or until the outbreak stops by other means.

“Had we been more on top of testing, maybe we wouldn’t have had to be quite so extreme,” Celine Gounder, an epidemiologist at New York University, told me. “Because we still have a [testing] shortage, we still have to have some way of dividing people who are infectious from people who are susceptible. Right now, in the absence of testing, you really have to do the social-distancing thing to the extreme.”

That doesn’t mean we wouldn’t still be practicing social distancing if we had better testing and surveillance. With a large disease outbreak, there was always bound to be some level of social distancing. But perhaps it would be more limited, more targeted, and — crucially — less open-ended. And maybe we wouldn’t be relying on social distancing quite as much to prevent potentially hundreds of thousands or millions of Covid-19 deaths, though experts caution it may be too late to change course on social distancing now.

“There’s just so much virus transmission happening around the world,” Grubaugh said. “Eventually, you would have had enough introductions happen that you would have sustained transmission in the US like we do now.” And that would require at least some social distancing no matter what, he added.

In an optimistic scenario, some experts said better surveillance could allow more limited social distancing in the future, at least temporarily. Testing can cut down on how long we need to social distance, since surveillance can help get outbreaks under control quicker. Schools might reopen and close only when early warning signs of the disease pop up locally, rather than as a blanket precautionary move. Smaller gatherings could be tolerated, or restaurants and other businesses could stay open, albeit in a limited capacity. But it’s hard to say, given all of the uncertainty surrounding Covid-19.

“Maybe that’s a way to be hopeful about how this could play out,” Gounder said.

But that requires a surveillance system robust enough that people could trust that the lack of cases means there really is little risk. The US is, at best, weeks away from achieving that. And that means it’s on all of us, at least for now, to social distance.

Better surveillance could reduce how much social distancing we need

In an ideal world, America would have widespread testing available for, at the very least, anyone who has symptoms of Covid-19. This would not only let those people get medical care and allow officials and experts to track who has the disease and where, but it would also enable contact tracing, which is when all of the people a sick person came into contact with are found and asked to go into self-quarantine as a precaution. This is all a crucial part of containing and even stopping a disease outbreak, especially during its early stages.

That did not happen in the US with Covid-19. First, the Trump administration refused to use the tests deployed by other countries and offered by the World Health Organization, seemingly out of concern that those tests weren’t accurate enough. Secondly, the homemade test the Centers for Disease Control and Prevention went with had technical problems, leading to further delays in getting widespread testing off the ground. Finally, a series of political, technical, and bureaucratic issues in recent weeks have further stalled testing, even as the Trump administration has promised “millions” of tests.

The CDC recommends several measures to help prevent the spread of Covid-19: Wash your hands often for at least 20 seconds.

Cover your cough or sneeze with a tissue, then throw it in the trash.

Clean and disinfect frequently touched objects.

Stay home as much as possible, and do not go out if you are sick.

Wear at least a cloth mask in certain public settings.

Contact a health worker if you have symptoms. Guidance may change. Stay informed, and stay safe, with Vox’s coronavirus coverage hub.

So several weeks after the first community transmission within the US, the country had tested fewer than 28,000 people as of March 15, according to the Covid Tracking Project. In comparison, South Korea had tested more than 66,000 people within a week of its first case of community transmission. As a result, US cases have flown under the radar, including in Washington state, where the coronavirus may have gone undetected for weeks in what’s now, as far as we know, the second-worst outbreak in the country.

“We know that there likely are unrecognized hotspots, that there are people transmitting with mild infections,” Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security, told me. “But we don’t know, technically, where they are. We don’t know how many cases we have. We know the number of confirmed cases is an underestimate, but we don’t know how much of an underestimate it is.”

The situation appears to be getting better as public and private labs finally scale up how much testing they can do. But experts caution this could take weeks or months — meaning we could be in the dark for a while, at a time when Covid-19 is spreading so rapidly that confirmed cases have been doubling within days.

In lieu of all this uncertainty, the public health motto is that it’s better to be safe than sorry. So people are being asked to do social distancing — which really means physically isolating themselves as much as possible. (Vox has a good guide on the rules of social distancing.)

“You’re left with this inability to do that kind of aggressive case finding and isolation,” Adalja said. “So what we’re doing is social distancing.”

Even if we scaled up testing, though, chances are we would still have to do a lot of social distancing. And it’s possible, even likely, that any future easing of social distancing as a result of better surveillance could be only temporary.

For example, Covid-19 may come back in waves, especially as we soften social-distancing measures and give the virus a chance to return while people still lack immunity. When that does happen, though, it’s also possible that better surveillance and more familiarity with the disease will limit what social-distancing measures are needed.

“The next round of social distancing will be activated more rapidly, because officials — and the public — will be more prepared,” doctors Ezekiel Emanuel, Susan Ellenberg, and Michael Levy wrote in the New York Times. “It should also be shorter, because we can assume that most of the people who were initially infected are likely to be immune next time around. But it will still disrupt people’s lives and the economy. We will still have canceled conferences and sporting events. People will not frequent restaurants and will not travel. The service industry will be severely curtailed. And it’s going to happen again and again.”

The idea here is to get to the point of South Korea, where very aggressive testing — up to 15,000 tests a day in a nation one-sixth as populous the US — and social distancing have let the country slow the spread of the coronavirus. That doesn’t mean South Korea is totally in the clear now; cases are still rising, and just like every other country, it will remain vulnerable to the disease until vaccines or other treatments are developed. But at least the light at the end of the tunnel is more visible.

At this point, we have to do social distancing. Millions of lives are at stake.

Regardless of how we got to this point, the experts I spoke to for this story reiterated one thing: We need to take social distancing seriously now — to protect not only ourselves but also everyone around us.

This isn’t going to be fun. It’s going to mean not having friends over, skipping parties, and cancelling reservations at favorite restaurants. Anything that isn’t truly essential has to go. Most people are social creatures, making this a real sacrifice for the majority.

There are also more serious consequences to social-distancing protocols. For people whose jobs don’t let them work from home, not showing up to the office — whether because they’re sick or their employer shut down — will cost them income and possibly health insurance. That will create a powerful incentive for people to go to work even if they’re experiencing symptoms. It’s largely up to employers and policymakers to make up for the loss of income with paid sick leave, food stamps, or even extra cash.

Unfortunately, we also don’t know how long this will be necessary. Nobody I spoke to believed it would only take a couple weeks, instead pointing to at least two months. There’s a good chance it could be necessary even beyond then — though whether it’s a year or 18 months of nonstop social distancing, or perhaps waves of social distancing every few months, is unclear.

“I don’t think anybody knows the answer to this now because we don’t know the trajectory of this outbreak in the United States,” Adalja said.

That’s partly a result of the lack of testing and surveillance, which makes it hard to track when diseases rise and fall. But it’s also a result of the fact that this disease is new, so we don’t know how it works, how long outbreaks typically last, or even if people necessarily develop lifelong immunity to it. (Several experts worry Covid-19 could become endemic and, similar to the flu, regularly come back in the future.)

In short, there’s a lot of unknowns. But that’s one reason why we need social distancing now: Without a concrete idea of just how bad this could all get, experts argue it’s better to take precautions instead of potentially letting things get bad — and letting people die — before we do anything.

The question is if people will stick to it.

Some experts said they’re hopeful that people will learn to adapt. People will learn to play board games online instead of in person. There will be happy hours over Skype or Zoom. There will be movie sessions over the phone or by text or Facebook messaging rather than in the same living room or theater. Things that may have seemed awkward before will now become necessary to maintain social interactions and relationships.

“We need to be creative about how we approach this,” Gounder said.

And maybe, as the reality of the pandemic settles in, people will realize this is something they just have to do.

But some experts also worry that a lot of people will let up and disobey the rules of social distancing, especially as it drags on for months and months.

“I don’t think people are prepared for that and I am not certain we can bear it,” Jennifer Nuzzo, a senior scholar at the Johns Hopkins Center for Health Security, previously told Vox. “I have no idea what political leaders will decide to do. To me, even if this is needed, it seems unsustainable.” She added that while she may just be feeling pessimistic, “it’s really hard ... to imagine this country staying home for months.”

In particular, experts worry that many Americans, still feeling healthy and mostly unaffected by Covid-19, will simply shrug off concerns about the virus. There’s a chance they’ll only start cutting back on their activities and socializing once the outbreak is visible to them, even though the whole point of social distancing is to prevent the outbreak from getting worse and more visible to people. In other words, a lot of people may react too slowly, potentially leading to hundreds of thousands of otherwise preventable deaths.

Social distancing could also be a victim of its own success: Officials and the public could see cases drop as a result of such measures and prematurely ease restrictions, only for Covid-19 cases to increase again. Epidemiological models back up such concerns, showing that pulling back on social distancing could lead to a spike in infections.

“It’s the paradox of public health: When you do it right, nothing happens,” Tara Smith, an epidemiologist at Kent State University, told me. “It’s when we have those breaks in public health where people do go out to parties … and somebody gets infected.”

The consequences here would be dire. Every single point of contact risks spreading the disease. If one person infects two or three others (as seems to be the case, on average, with unabated coronavirus), those people could infect two or three more, and so on and so on. One slip-up could lead to dozens, if not hundreds, of infections down the line; in South Korea, one person was reportedly the initial source for more than 1,000 new infections.

The flip side is that if we do this right, we could avert potentially hundreds of thousands of deaths. If that feels abstract, experts advise thinking of it in more concrete terms: People you know today might be alive next year only if we all take social distancing seriously. In the absence of better surveillance, that’s what we’re relying on — almost entirely — for now.