Two types of people took to social media on Saturday night: the ones who snuggled up tight with their books, cats and hand-sanitizer — and the ones who did not.

Those other people were “spoiled children,” tweeted the hand-sanitizers. They shared pictures of crowded bars and threw up their hands at people who went ahead with their weddings. Didn’t they know that covid-19 thrives in tightly packed, poorly-ventilated, confined spaces? Don’t they care about their grandparents?

Well, yes. I’m sure they do care about their grandparents. But for some reason, a surprising number of people decided it would be a good idea to leave their homes in the middle of a pandemic — when school, work, religious services and March Madness have all been canceled — to go out and have a good time.

Americans should adopt a policy of “social distancing,” the Centers for Disease Control and Prevention announced earlier this month. As the virus quickly spreads across the country, experts are saying, people need to stay away from each other, avoiding large gatherings at all costs, particularly when they are indoors, particularly when there are a lot of people touching each other. A crowded bar is “perhaps the absolute worst place for transmission,” said Marc Lipsitch, a professor of epidemiology at Harvard’s T.H. Chan School of Public Health. And while younger people might feel immune to the virus — the people most likely to get seriously ill are over 60 — they need to consider the impact they’re having on others, Lipsitch said.

“Social distancing is not only about individual protection. It’s about trying to reduce the overall size of the threat. If a young, healthy person gets the virus, the virus is more likely to be passed on to elderly people and immunocompromised people.”

The facts are there: Going to a crowded bar right now is, unquestionably, a truly terrible idea. But would I say that to my friend who went to a bar on Saturday and then posted on Instagram about it?

Probably not. But I’m starting to think that I should.

These kinds of conversations are uncomfortable. When you call someone out for their lack of social distancing, you’re “judging their ability to judge the situation,” said Tim Muehlhoff, a professor of communication at Biola University. It can feel deeply awkward, he said, because you’re basically saying you know better than they do, when you don’t have the credentials to back that up.

But maybe it’s time for us all to embrace the awkwardness: to be “that friend” who backs out of brunch with a group of friends, and then explains why. Social pressure and information-sharing can actually change behavior, said Crystal Watson, a senior scholar at the Johns Hopkins Center for Health Security, who specializes in public health risk assessment. In this situation, she said, it can probably save lives.

“We should be worried and we should take this seriously,” she said. “More honesty and openness and information is a good thing here.”

I asked Lipsitch, Muehlhoff and Watson to help me think through a few different scenarios. I wanted to know: What do you say, exactly, when you feel like you have to say something?

Watson, expert on public health preparedness: What I would do, and what I probably will do, because I’m on Instagram, and have seen this today: I would get in touch with those people directly, send them a message or give them a call and just say, “Hey, I’m really worried about this. I’m worried about you. I really think we should be taking this seriously.” Of course, if you do that, you risk that people might be annoyed. But at this point I think it is really important.

Lipsitch, expert on epidemiology: Keep in mind that I’m 50 and hang out with other epidemiologists, so I’m not an expert in communicating with epidemiologically-naive millennials. But I think I would just say, “Hey, this is really serious. Lots of us are inconveniencing ourselves and ruining our social lives to some degree. You should be doing this because this is life or death for a lot of people.” And if I knew their grandparent, or parent, or another immunocompromised relative, I might say, “Look, it’s people like that who you’re protecting.”

Muehlhoff, expert on communication: I would message them and say, “Hey, I saw your photo. It looks like you had a fun time. Can we talk?” Then I would find out why they thought it was okay to go to the bar, in light of the coronavirus. I’m gathering information on how they’re approaching the situation. Then I’d ask, “Generally speaking, why do you believe it was okay to go? What have you been reading on the topic that you’ve found to be helpful?” Find out what you agree on. Then finally, you can be a little more pointed, something like, “Do you think it’s worth it to go to the bar?” Remember that your tone is everything here.

You don’t want to go into the conversation super angry, thinking, “I can’t believe you just posted at a bar. You’re an idiot.” You want to approach it like, “This is me learning with you,” not, “This is me setting you straight.” You’ll never convince them that way.

Watson, expert on public health preparedness: I would say, “Look at Italy right now. We’re seeing hospitals totally overwhelmed with severe illness. People are dying unnecessarily and that is what we’re trying to avoid here.”

Lipsitch, expert on epidemiology: I would tell this friend that we need to kick our imaginations into high gear. And I know that’s hard. Even I find it hard to imagine that in a week my health care system could be completely collapsing around me, even though I’m having a relatively normal day today. But it was hard for the Italians and the Iranians and the Spanish to imagine that, too. Part of being a good friend is telling people when they’re wrong.

Watson, expert on public health preparedness: [Experts] right now are more worried about large gatherings in confined spaces, like clubs and restaurants, than smaller gatherings inside the home. But still, I would definitely ask some questions, set some ground rules. I would ask the host to tell everyone, “If you’re sick, tell the group and don’t come.” And if someone gets sick after the gathering, they need to say something.

Lipsitch, expert on epidemiology: I got an email a few days ago from a parent of one of our kids’ friends. She was hosting a “quarantine party.” She was trying hard, saying we’d do something outside with lots of handwashing or maybe a few board games with a couple of people inside. I wrote back and said, “As an epidemiologist, I feel like I need to say, I think smaller groups are better, outdoors is better. Why don’t we do it in pairs or triples?” Some people might say, even that is too loose, but I have a strong sense that we need to balance our long-term social and mental health with disease control.

Muehlhoff, expert on communication: If it’s a close friend, I would say something like, “Hey, we’re probably overreacting but right now we’re just kind of trying to avoid crowds. We love you guys. We’re just trying to think through what we should do at this point, because again, we have kids. So at this point, we’re going to pass, but man, thank you so much.” What I’m doing here, I’m putting it on myself. It’s my fault. I’m not putting it on them. If I said to my friend, “Do you really think it’s wise to do this, guys?” — that would be questioning their discernment.

Watson, expert on public health preparedness: It’s really hard to tell someone to cancel their wedding. I don’t think that’s going to go over well. But if I’m in the bridal party, and I know that person really well, then I probably would say, “I know this is a really important event and I don’t want it to be ruined but what if, by some chance, people come and then get sick at your wedding. So have you thought about whether you might delay the wedding? I think vendors will probably be somewhat more lenient with contracts at this point, so have you explored that option?”

And if the friend chooses to go forward anyway, I would maybe suggest they contact their guests and say, “If you feel uncomfortable with this, we don’t blame you for not coming. If you have underlying health conditions, you might want to stay away.” I’d tell my friend to give guests the choice, make them feel like they’re not going to be angry with them if they don’t come.

Lipsitch, expert on epidemiology: If it’s an indoor wedding I would say, “No public health authority thinks it’s a good idea right now to have so many people in the same room. You either need to move the wedding outside, or you need to find some other date.”

Muehlhoff, expert on communication: I would say, “Hey, I’m just curious. There are people coming to this wedding who are over 50. I’m just wondering what you guys are thinking concerning them.” If they say, “Oh, they’ll be fine,” then I’ll ask them to unpack that for me. I’d try to find some common ground. Ultimately, I’d say something like, “I’m going to be honest with you. I’m a little uncomfortable with grandpa and grandma being there. Is it wise to do this now?” You want to make sure you have a conversation, not a monologue. Again, put it on yourself. Say, “I personally am a little wigged by this.”

Watson, expert on public health preparedness: In that situation I would definitely speak up and say, “We have an opportunity to avoid our loved ones getting sick here. We should postpone this, we can have this later on. We do not want to be responsible for getting our older relatives sick.” I would explain that the death rates among elderly people are very high, and this is a scary thing for older people. You want to give them the facts, tell them what you’ve read, what we know about the disease, particularly the data coming out of China and Italy.

Lipsitch, expert on epidemiology: I might suggest that we designate one or two family members to go down, instead of everyone all together. If the grandparents are not good at FaceTime, spend some of the time there setting them up, making sure they have a way to get groceries and medicine. Turn it into an opportunity to make sure the grandparents are as connected as they can be to the family in the upcoming months. Because it could be a while.